Solar power generation system

Abstract

To reduce glaring caused by reflection of sun light with respect to a photovoltaic power generation system.SOLUTION: A photovoltaic power generation system includes a plurality of solar cell modules each installed in a runway in an airport or a land along the longitudinal direction of a landing strip. The plurality of solar cell modules have a plurality of groups including a first group and a second group. The first group is composed of a plurality of first solar cell modules, and the second group is composed of two or more solar cell modules including one or more second solar cell modules. A reflection rate of light on each of light receiving surfaces of the one or more second solar cell modules is smaller than a reflection rate of light on each of light receiving surfaces of the plurality of first solar cell modules. An estimated irradiance of reflected light incident on a cockpit of a flying aircraft or a control room of a control tower according to a reflection of sun light in the plurality of solar cell modules is equal to or less than a predetermined irradiance.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present disclosure relates to a solar power generation system.

Background Art

[0002] For solar power generation systems, there is an analysis tool that calculates the irradiance of the reflected sunlight on the surface of a solar cell module that is incident on the eyes of a virtual observer (see, for example, the description in Patent Document 1).

[0003] There is also a technique for reducing glare caused by reflection of sunlight on the surface of a solar cell module by providing irregularities on the surface of a cover glass of the solar cell module (see, for example, the description in Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problem to be Solved by the Invention

[0005] Solar power generation systems have room for improvement in terms of reducing glare caused by the reflection of sunlight.

Means for Solving the Problem

[0006] A solar power generation system is disclosed.

[0007] One embodiment of a solar power generation system comprises a plurality of solar cell modules. The plurality of solar cell modules are each installed on land along the longitudinal direction of a runway or landing strip at an airport. The plurality of solar cell modules comprises a plurality of groups, including a first group and a second group. The first group consists of a plurality of first solar cell modules. The second group consists of two or more solar cell modules, including one or more second solar cell modules. The reflectance of light on the light-receiving surface of each of the one or more second solar cell modules is smaller than the reflectance of light on the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its diurnal motion throughout the year, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the plurality of solar cell modules, is less than or equal to a predetermined irradiance. [Effects of the Invention]

[0008] Regarding solar power generation systems, they can reduce glare caused by the reflection of sunlight. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic plan view showing an example of the configuration of an airport where a solar power generation system according to the first embodiment is installed. [Figure 2] Figure 2 is a schematic perspective view showing an example of a part of the configuration of an airport where a solar power generation system according to the first embodiment is installed. [Figure 3] Figure 3 is a schematic perspective view showing an example of the configuration of a solar cell array corresponding to one group of modules. [Figure 4] Figure 4 is a plan view showing an example of the appearance of the light-receiving side of a solar cell module. [Figure 5] Figure 5 is a schematic cross-sectional view showing an example of a hypothetical cross-section at position VV of the solar cell module in Figure 4. [Figure 6] Figure 6 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system according to the first embodiment is installed. [Figure 7] Figure 7 is a schematic diagram illustrating an example of how reflected light, generated by specular reflection in response to sunlight irradiation in a solar power generation system, enters the eyeball of a subject. [Figure 8] Figure 8 is a schematic diagram illustrating an example of the distribution of reflected light intensity when non-uniform diffuse reflection occurs on a light-receiving surface in response to sunlight irradiation. [Figure 9] Figure 9 is a schematic diagram illustrating an example of how the first reflection region, which reflects sunlight, is projected onto the retina of the subject's eyeball. [Figure 10] Figure 10 is a schematic plan view illustrating an example of the configuration of an airport where a solar power generation system is installed, based on a reference example in which all of the multiple module groups are tentatively designated as the first module group. [Figure 11] Figure 11 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system, according to one reference example, is installed. [Figure 12] Figure 12 is a flowchart showing an example of a flow chart for determining the relationship between the visual angle related to the first reflection region and the estimated irradiance corresponding to the retinal irradiance when the sun performs its annual diurnal motion. [Figure 13] Figure 13 is an illustrative diagram illustrating an example of the relationship between the optical path of specularly reflected light generated in response to sunlight irradiation on the light-receiving surface of a photovoltaic power generation system and a specific position. [Figure 14] Figure 14 is a graph showing an example of the relationship between the visual angle related to the first reflection region, the estimated irradiance, the retinal irradiance, and the critical irradiance. [Figure 15] Figure 15 is a schematic plan view showing a part of the configuration of an airport where a solar power generation system according to the first reference example is installed. [Figure 16] Figure 16 is a schematic graph showing an example of the relationship between the visual angle related to the first reflection region of Group A, the retinal irradiance corresponding to the estimated irradiance, and the critical irradiance for the eyeball of an aircraft pilot in landing approach to an airport where a solar power generation system according to the first reference example is installed. [Figure 17]Figure 17 is a schematic plan view showing a part of the configuration of an airport where a solar power generation system according to a first specific example of the first embodiment is installed. [Figure 18] Figure 18 is a schematic graph showing an example of the relationship between the visual angle related to the first reflection region of group A, the retinal irradiance corresponding to the estimated irradiance, and the critical irradiance for the eyeball of an aircraft pilot in landing approach to an airport where a solar power generation system according to the first embodiment is installed. [Figure 19] Figure 19 is a schematic perspective view showing an example of a partial configuration of the module group. [Figure 20] Figure 20 is a schematic plan view showing a part of the configuration of an airport where a solar power generation system according to the second reference example is installed. [Figure 21] Figure 21 is a schematic graph showing an example of the relationship between the visual angle related to the first reflection region of Group A, the retinal irradiance corresponding to the estimated irradiance, and the critical irradiance for the eyeball of an aircraft pilot in landing approach to an airport where a solar power generation system according to the second reference example is installed. [Figure 22] Figure 22 is a schematic graph showing an example of the relationship between the visual angle related to the first reflection region of Group B, the retinal irradiance corresponding to the estimated irradiance, and the critical irradiance for the eyeball of an aircraft pilot in landing approach to an airport where a solar power generation system according to the second reference example is installed. [Figure 23] Figure 23 is a schematic plan view showing a part of the configuration of an airport where a solar power generation system according to a second specific example of the first embodiment is installed. [Figure 24] Figure 24 is a schematic graph showing an example of the relationship between the visual angle related to the first reflection region of group A, the retinal irradiance corresponding to the estimated irradiance, and the critical irradiance for the eyeball of an aircraft pilot in landing approach to an airport where a solar power generation system according to a second specific example of the first embodiment is installed. [Figure 25] Figure 25 is a schematic plan view illustrating an example of the relationship between the spacing of rows of solar cell modules in the first and second groups, and the spacing between the first and second groups. [Figure 26]Figure 26 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where the first example of the solar power generation system according to the second embodiment is installed. [Figure 27] Figure 27 is an illustrative diagram showing an example of the positional relationship between a first pass region of specularly reflected light generated by two or more light-receiving surfaces of the first group in response to sunlight irradiation, a second pass region of specularly reflected light generated by two or more light-receiving surfaces of the second group in response to sunlight irradiation, and a landing flight path in a first example of a photovoltaic power generation system according to the second embodiment. [Figure 28] Figure 28 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a second example of the solar power generation system according to the second embodiment is installed. [Figure 29] Figure 29 is an illustrative diagram showing an example of the positional relationship between a first pass region of specularly reflected light generated by two or more light-receiving surfaces of the first group in response to sunlight irradiation, a second pass region of specularly reflected light generated by two or more light-receiving surfaces of the second group in response to sunlight irradiation, and a landing flight path in a second example of a photovoltaic power generation system according to the second embodiment. [Figure 30] Figure 30 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system according to the third embodiment is installed. [Figure 31] Figure 31 is a schematic plan view showing an example of the configuration of an airport where a solar power generation system according to the fourth embodiment is installed. [Figure 32] Figure 32 is a schematic plan view showing an example of the configuration of an airport where a solar power generation system according to the fifth embodiment is installed. [Figure 33] Figure 33 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system according to the sixth embodiment is installed. [Figure 34] Figure 34 is a schematic cross-sectional view showing an example of a hypothetical cross-section at the airport location XXXIV-XXXIV in Figure 33. [Figure 35] Figure 35 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system according to the seventh embodiment is installed. [Figure 36] Figure 36 is a schematic cross-sectional view showing an example of a hypothetical cross-section at the airport location XXXVI-XXXVI in Figure 35. [Figure 37] Figure 37 is a schematic perspective view showing an example of an aircraft in landing approach to an airport where a solar power generation system according to the eighth embodiment is installed. [Figure 38] Figure 38 is a schematic cross-sectional view showing an example of a hypothetical cross-section at the airport location XXXVIII-XXXVIII in Figure 37. [Figure 39] Figure 39 is a schematic perspective view showing an example of a part of the configuration of an airport where a solar power generation system according to the ninth embodiment is installed. [Figure 40] Figure 40 is a schematic block diagram showing an example of the general configuration of a photovoltaic power generation system according to the 10th embodiment. [Figure 41] Figure 41 is a schematic block diagram showing another example of the general configuration of the photovoltaic power generation system according to the 10th embodiment. [Figure 42] Figure 42 is a schematic perspective view showing an example of an aircraft in landing approach to an airport equipped with other solar power generation systems. [Figure 43] Figure 43 is a schematic perspective view showing an example of an aircraft in landing approach to an airport equipped with other solar power generation systems. [Modes for carrying out the invention]

[0010] Solar power generation systems, which generate electricity using sunlight as a renewable energy source, are well known. Installing a solar power generation system requires a certain amount of space. One such location that is attracting attention is the rooftops of buildings and vacant land. Examples of vacant land that are being considered include the land surrounding airport runways.

[0011] In this solar power generation system, the reflected sunlight from the surface (also called the light-receiving surface) of the solar cell modules may cause glare to people in vehicles and inside buildings in the vicinity of the solar power generation system. In particular, when installing a solar power generation system on land surrounding an airport runway, glare prevention is important in one or more spaces, such as the cockpit and / or air traffic control room, for the safe operation of aircraft.

[0012] To reduce the glare caused by the reflection of sunlight, it is conceivable to reduce specular reflection of sunlight on the light-receiving surface of the solar cell module by creating irregularities on the light-receiving surface of the solar cell module.

[0013] However, in solar cell modules, while creating irregularities on the light-receiving surface reduces specular reflection of sunlight on the surface, it is possible that the amount of light (also called light intensity) incident on the solar cell element will decrease, leading to a decrease in power generation. In other words, a decrease in power generation may be the trade-off for reducing glare.

[0014] Furthermore, to reduce glare caused by reflected sunlight, one possible strategy is to avoid installing solar cell modules in specific locations around the solar power generation system where glare would otherwise occur.

[0015] However, in a solar power generation system, a decrease in the number of solar cell modules can lead to a decrease in power generation.

[0016] Therefore, there is room for improvement in solar power generation systems in terms of reducing glare caused by reflected sunlight.

[0017] Therefore, the inventors of this disclosure have created a technology that can reduce glare caused by the reflection of sunlight in a solar power generation system.

[0018] This will be explained below with reference to the drawings, describing various embodiments. In the drawings, the same reference numerals are used for parts having the same or similar configuration and function, and redundant explanations will be omitted in the following description. The drawings schematically show various configurations, etc. Figures 1 to 3, 6, 10, 11, 15, 17, 20, 23, 26, 28, 30 to 39, 42, and 43 each have a right-handed XYZ coordinate system. In this XYZ coordinate system, one direction along the horizontal plane is defined as the +X direction, another direction perpendicular to the +X direction and along the horizontal plane is defined as the +Y direction, and the vertically upward direction is defined as the +Z direction. Figures 4, 5, 8, and 19 each have a right-handed xyz coordinate system. In this xyz coordinate system, the direction in which the light-receiving surface 30s of the solar cell module 3 is tilted is defined as the -y direction, the direction perpendicular to the -y direction and along the light-receiving surface 30s is defined as the +x direction, and the normal direction of the light-receiving surface 30s is defined as the +z direction. The normal direction of the light-receiving surface 30s is the direction that is perpendicular to the light-receiving surface 30s and away from the light-receiving surface 30s. Figure 25 shows the x-axis of the above xyz coordinate system. Figures 7 and 13 each show the z-axis of the above xyz coordinate system. Figures 15, 17, 20, and 23 each show the four cardinal directions: east, west, north, and south. The four cardinal directions are indicated by the letters E for East, W for West, S for South, and N for North. Figures 19 and 25 each include an arrow indicating one horizontal direction along the x-direction (also called the first horizontal direction) Dr1, and an arrow indicating a second horizontal direction (also called the second horizontal direction) Dr2 perpendicular to the first horizontal direction Dr1.

[0019] Expressions indicating relative or absolute positional relationships (e.g., "located on a line," "in one direction," "along one direction," "parallel," "orthogonal," "perpendicular," or "center"), unless otherwise specified, may not only strictly describe the positional relationship but also describe a state that is relatively displaced in terms of angle or distance within a tolerance or range that yields a similar level of function. Expressions indicating equality (e.g., "identical," "equal," or "homogeneous"), unless otherwise specified, may not only describe a state that is quantitatively exactly equal but also describe a state where there is a tolerance or a difference that yields a similar level of function. Expressions indicating shape (e.g., "rectangular," "quadrilateral," or "cylindrical"), unless otherwise specified, may not only strictly describe the shape geometrically but also describe a shape that has features such as concavities and chamfers within a range that yields a similar level of effect. Expressions that "come with," "include," or "have" one component are not exclusive expressions that exclude the existence of other components. Unless otherwise specified, "above" and "below" can refer to situations where two elements are in contact, as well as situations where two elements are separated.

[0020] <1. First Embodiment> The solar power generation system 100 according to the first embodiment will be described with reference to Figures 1 to 6. The solar power generation system 100 is a solar power generation system (also called the airport solar power generation system) installed on the grounds of the airport 200.

[0021] <1-1. Airport Structure> As shown in Figures 1 and 2, airport 200 includes, for example, runway 1, landing strip 2, control tower 6, and airport land 9.

[0022] Runway 1 is a straight, paved road used for aircraft 5 to take off from and land at airport 200. Runway 1 has a road surface that aligns with the horizontal plane. Runway 1 may have an elongated rectangular shape when viewed from above. In this disclosure, unless otherwise specified, "view from above" means a view from directly above and directly below. Runway 1 has various markers, such as runway centerline markers 1c and target point markers 1a.

[0023] Runway centerline marker 1c indicates the center of runway 1 in the short direction (also called the width direction) and also indicates the centerline located along the longitudinal direction of runway 1. Runway centerline marker 1c is drawn as a dashed line along the centerline of runway 1. The short direction (width direction) of runway 1 is the direction perpendicular to the longitudinal direction of runway 1 and along runway 1. From another perspective, the longitudinal direction of runway 1 is the longitudinal direction of the runway surface of runway 1, and the short direction (width direction) of runway 1 is the short direction (width direction) of the runway surface of runway 1. In the example shown in Figures 1 and 2, the longitudinal direction of runway 1 is the direction along the +X direction, and the short direction (width direction) of runway 1 is the direction along the +Y direction.

[0024] A target point marker 1a is a marker indicating the target point (also called the landing target point) on runway 1 where the tires of the aircraft 5 should touch down during landing. A target point marker 1a has two parallel rectangular marks on either side of the centerline of runway 1. Runway 1 may have, for example, two target point markers 1a. The two target point markers 1a include a first target point marker 1a1 and a second target point marker 1a2. The second target point marker 1a2 is a different target point marker 1a from the first target point marker 1a1. The first target point marker 1a1 is located on the side of the first end of runway 1 in the longitudinal direction. The second target point marker 1a2 is located on the side of the second end of runway 1, opposite to the first end in the longitudinal direction. In the example shown in Figure 1, the first end of runway 1 in the longitudinal direction is the end located on the +X side of runway 1, and the second end of runway 1 in the longitudinal direction is the end located on the -X side of runway 1. In the example shown in Figure 1, aircraft 5 can land on runway 1 from either the first end side or the second end side of runway 1. From another perspective, aircraft 5 can land by approaching runway 1 from the first end side and touching down its tires with the first target marker 1a1 or in the vicinity of the first target marker 1a1, or by approaching runway 1 from the second end side and touching down its tires with the second target marker 1a2 or in the vicinity of the second target marker 1a2.

[0025] In the example shown in Figures 1 and 2, some parts of Runway 1 have been omitted to avoid complicating the drawing, and various signs and lighting equipment on Runway 1 have also been omitted as appropriate.

[0026] Landing strip 2 is the area surrounding runway 1, designed to ensure the safe takeoff and landing of aircraft 5. In Figure 1, landing strip 2 is conveniently hatched with a sandy pattern. Landing strip 2 is located along runway 1. In other words, the longitudinal direction of landing strip 2 is aligned with the longitudinal direction of runway 1.

[0027] Control Tower 6 is a tower-like facility that provides air traffic control at Airport 200. For example, Control Tower 6 is located next to Runway 1 at Airport 200. During air traffic control, it communicates with aircraft 5 and provides instructions regarding takeoffs, landings, and other related matters.

[0028] Airport site 9 is the site for facilities necessary to maintain the functions of Airport 200.

[0029] <1-2. Configuration of a solar power generation system> The solar power generation system 100 comprises multiple solar cell modules 3. The multiple solar cell modules 3 are installed on land along the longitudinal direction of runway 1 or landing strip 2 at airport 200. The multiple solar cell modules 3 may be installed on land along the longitudinal direction of runway 1, or on land along the longitudinal direction of landing strip 2, or on land along both runway 1 and landing strip 2.

[0030] The land along the longitudinal direction of runway 1 may include a pair of land parcels (also called the first pair of land parcels) that are located on either side of runway 1 in the short direction (width direction) of runway 1, or it may include either one of the first pair of land parcels. The first pair of land parcels may include the landing strip 2, or it may include airport land 9 located along the landing strip 2, or it may include the landing strip 2 and the airport land 9 located along the landing strip 2.

[0031] The land along the longitudinal direction of landing strip 2 may include a pair of land parcels (also called a second pair of land parcels) that are located on either side of landing strip 2 in the short direction (width direction) of landing strip 2, or it may include either one of these second pair of land parcels. The second pair of land parcels may include airport land 9 located along landing strip 2. In the example shown in Figure 1, the longitudinal direction of landing strip 2 is along the +X direction, and the short direction (width direction) of landing strip 2 is along the +Y direction.

[0032] Multiple solar cell modules 3 have multiple groups (also called groups or module groups) 3g, each composed of two or more solar cell modules 3. Multiple module groups 3g include a first module group (also called the first group) 3g1 and a second module group (also called the second group) 3g2. The first group 3g1 is composed of multiple first solar cell modules 31. The second group 3g2 is composed of two or more solar cell modules 3, each including one or more second solar cell modules 32.

[0033] In Figure 1, each of the multiple module groups 3g is conveniently represented by a single rectangle. Also in Figure 1, the first group 3g1 is hatched with a diagonal line rising to the right, and the second group 3g2 is hatched with a diagonal line rising to the left. In one example shown in Figure 1, airport 200 has 11 module groups 3g, including 7 first group 3g1 modules and 4 second group 3g2 modules. In one example shown in Figure 1, the 11 module groups 3g are installed on the airport site 9. In one example shown in Figure 2, airport 200 and the solar power generation system 100 are depicted, including a portion of runway 1, two second group 3g2 modules, a portion of two first group 3g1 modules, and the control tower 6, with the other components omitted.

[0034] The two or more solar cell modules 3 constituting the second group 3g2 may, for example, include only a plurality of second solar cell modules 32, or they may include a first solar cell module 31 and a second solar cell module 32. In the example shown in Figures 1 and 2, the two or more solar cell modules 3 constituting the second group 3g2 include only a plurality of second solar cell modules 32.

[0035] As shown in Figures 2 and 3, for example, each of the multiple module groups 3g may have two or more solar cell modules 3 fixed to one or more mounting frames 4. In other words, the photovoltaic power generation system 100 may include multiple solar cell arrays, each consisting of one or more mounting frames 4 and two or more solar cell modules 3.

[0036] In the example shown in Figures 2 and 3, each module group 3g comprises multiple solar cell modules 3 fixed to multiple mounting frames 4. In the second group 3g2 in the example in Figures 2 and 3, three rows of solar cell modules 3, each composed of 21 solar cell modules 3 arranged along the +X direction, are arranged along the +Y direction. In other words, 63 solar cell modules 3 are arranged in a matrix. The number and arrangement of one or more mounting frames 4 and two or more solar cell modules 3 are not limited to the numbers and arrangements in the example in Figures 2 and 3, but may vary. For example, the number of mounting frames 4 to which two or more solar cell modules 3 constituting one module group 3g are fixed may be one, or any number of two or more. The number of solar cell modules 3 constituting one module group 3g may be two, or any number of three or more.

[0037] The mounting frame 4 secures the solar modules 3 to the airport land 9 or landing strip 2 within the airport 200 site. If the mounting frame 4 is located on the airport land 9, the mounting frame 4 secures the solar modules 3 to the airport land 9. If the mounting frame 4 is located on the landing strip 2, the mounting frame 4 secures the solar modules 3 to the landing strip 2. The mounting frame 4 may be secured to the land of the airport land 9 or landing strip 2 by, for example, a concrete foundation. The mounting frame 4 may have, for example, a structure combining columns and beams (also called a frame structure). For example, one solar module 3 may be secured to one mounting frame 4, or two or more solar modules 3 may be secured to one mounting frame 4, or one solar module 3 may be secured to two or more mounting frames 4.

[0038] As shown in Figures 4 and 5, each of the multiple solar cell modules 3 includes, for example, a solar cell 303c and a light-transmitting member 301 that protects the solar cell 303c from the light-receiving surface 30s. The light-receiving surface 30s is the surface of the solar cell module 3 that receives sunlight SL0. From another perspective, for example, the light-receiving surface 30s is the surface of the solar cell module 3 that faces upward or diagonally upward.

[0039] Each solar cell module 3 includes, for example, a solar cell panel 30p and a frame 30f that reinforces the outer edge of the solar cell panel 30p.

[0040] The solar cell panel 30p has a first surface F1 which mainly constitutes a light-receiving surface 30s that receives light, and a second surface F2 located on the opposite side of the first surface F1. The solar cell panel 30p has, for example, a light-transmitting member 301 as a first protective layer, a first sealing layer 302, a photoelectric conversion unit 303, a second sealing layer 304, a back surface protective member 305 as a second protective layer, and a terminal box 30b, in that order from the first surface F1 side.

[0041] The light-transmitting member 301 is located, for example, on the first surface F1 side of the photoelectric conversion unit 303. Here, for example, the surface of the light-transmitting member 301 opposite to the photoelectric conversion unit 303 (also called the first surface) constitutes the first surface F1. The light-transmitting member 301 has, for example, the role of protecting the photoelectric conversion unit 303 and the role of sealing the photoelectric conversion unit 303. The light-transmitting member 301 has, for example, light transmittance to light of a specific range of wavelengths. The specific range of wavelengths includes, for example, the wavelengths of light that the photoelectric conversion unit 303 can photoelectrically convert. If the specific range of wavelengths includes wavelengths of light with high irradiation intensity from sunlight SL0, the photoelectric conversion efficiency of the solar cell module 3 can be improved. As the material of the light-transmitting member 301, for example, glass may be used. The material of the light-transmitting member 301 is not limited to this, and may be, for example, a resin such as acrylic or polycarbonate, or another light-transmitting material. For example, the glass used may be a sheet of white glass with a thickness of approximately 2 millimeters (mm) to 5 mm, tempered glass, or heat-reflective glass, or other materials with high light transmittance. The thickness and type of glass are not limited to these, and various thicknesses and types of glass may be used.

[0042] The first sealing layer 302 is located between the light-transmitting member 301 and the photoelectric conversion unit 303. The second sealing layer 304 is located between the photoelectric conversion unit 303 and the back surface protective member 305. In other words, the first sealing layer 302 and the second sealing layer 304 are located in a state where they are filled between the light-transmitting member 301 and the back surface protective member 305, covering the photoelectric conversion unit 303. The first sealing layer 302 and the second sealing layer 304 have, for example, the roles of holding the photoelectric conversion unit 303 and sealing the photoelectric conversion unit 303. The first sealing layer 302 has light transmittance to light within the specific range of wavelengths described above. The second sealing layer 304 may or may not have light transmittance to light within the specific range of wavelengths described above. Examples of materials for the first sealing layer 302 and the second sealing layer 304 include thermosetting resins. Examples of thermosetting resins include resins primarily composed of ethylene vinyl acetate copolymer (EVA) or poly-vinyl butyral (PVB). The thermosetting resin may also contain a crosslinking agent. Here, "main component" refers to the component present in the largest proportion (also called the highest content).

[0043] The photoelectric conversion unit 303 includes, for example, a plurality of solar cells (also called solar cell elements) 303c, a plurality of first wiring materials W1, and a plurality of second wiring materials W2. In the example shown in Figures 4 and 5, the plurality of solar cells 303c are arranged in two dimensions. More specifically, the photoelectric conversion unit 303 includes a plurality of cell rows S1. Figures 4 and 5 show an example in which the photoelectric conversion unit 303 includes six cell rows S1, but it is not limited to this. For example, the photoelectric conversion unit 303 may include five or fewer or seven or more cell rows S1. Each cell row S1 includes a plurality of solar cells 303c and a plurality of first wiring materials W1. Figures 4 and 5 show an example in which each cell row S1 includes eight solar cells 303c, but it is not limited to this. For example, each cell row S1 may include seven or fewer or nine or more solar cells 303c. Multiple first wiring materials W1 electrically connect, for example, adjacent solar cells 303c among multiple solar cells 303c. Multiple second wiring materials W2 electrically connect adjacent cell rows S1 among multiple cell rows S1.

[0044] The back surface protective member 305 is located, for example, on the second surface F2 side of the photoelectric conversion unit 303. Here, for example, the surface of the back surface protective member 305 opposite to the photoelectric conversion unit 303 constitutes the second surface F2. The back surface protective member 305 has, for example, the role of protecting the photoelectric conversion unit 303 and the role of sealing the photoelectric conversion unit 303. The back surface protective member 305 may, for example, be translucent to light within the specific range of wavelengths described above, or it may not be translucent. For example, the back surface protective member 305 can be a flexible sheet-like member (also called a sheet member) or a plate-like member. For the sheet member, various materials such as resin can be used. For the plate-like member, various materials such as glass, acrylic, or polycarbonate resin can be used.

[0045] The terminal box 30b can, for example, take the output obtained from the photoelectric conversion unit 303 to the outside. The terminal box 30b is located, for example, on the second surface F2. The terminal box 30b can be fixed to the second surface F2 using, for example, a resin such as silicone sealant. The terminal box 30b may be located in a different place on the solar cell panel 30p. The terminal box 30b includes, for example, a box body, a terminal board, and a cable. In this case, various materials such as modified polyphenylene ether resin (modified PPE resin) or polyphenylene oxide resin (PPO resin) can be used for the material of the box body. The terminal board is located inside the box body. The second wiring material W2 of the photoelectric conversion unit 303 may be connected to the terminal board. The cable is connected to the terminal board, for example, and can lead power to the outside of the box body.

[0046] The frame 30f has the function of holding the solar cell panel 30p. The frame 30f is positioned, for example, along the outer periphery of the solar cell panel 30p. The frame 30f includes, for example, a portion having a U-shaped cross-sectional structure that extends from a position along the first surface F1 to a position along the second surface F2 on the outer periphery of the solar cell panel 30p. The frame 30f can be manufactured, for example, by extrusion molding of aluminum.

[0047] In the first embodiment, the reflectance of light on the light-receiving surface 30s (also called the first light-receiving surface 30s1) of the first solar cell module 31 is greater than the reflectance of light on the light-receiving surface 30s (second light-receiving surface 30s2) of the second solar cell module 32. In other words, the reflectance of light on the second light-receiving surface 30s2 of the second solar cell module 32 is less than the reflectance of light on the first light-receiving surface 30s1 of the first solar cell module 31. The reflectance of light referred to here may be, for example, the ratio of the peak intensity of the reflected light at which the specular reflection component is maximized to the intensity of the incident light when light is incident on the light-receiving surface 30s at a predetermined incident angle. Here, for example, by making the roughness or irregularity of the second light-receiving surface 30s2 greater than that of the first light-receiving surface 30s1, the reflectance of light on the second light-receiving surface 30s2 can be made smaller than the reflectance of light on the first light-receiving surface 30s1.

[0048] For example, if the translucent member 301 is a glass plate (also called a glass sheet), the unevenness of the light-receiving surface 30s can be achieved by forming the unevenness on one side of the glass sheet during its manufacture. In this case, for example, when manufacturing a glass sheet by passing molten glass between two water-cooled rolls arranged vertically, if the surface of the lower of the two water-cooled rolls has a pattern formed by engraving or the like, the unevenness can be formed on one side of the glass sheet by transferring that pattern. In the examples of Figures 2, 3, and 6, the first light-receiving surface 30s1 does not have hatching, while the second light-receiving surface 30s2 has hatching using a sandy pattern.

[0049] Here, because the roughness or irregularity of the second light-receiving surface 30s2 is greater than that of the first light-receiving surface 30s1, when the first solar cell module 31 and the second solar cell module 32 are irradiated with the same amount of sunlight SL0 at the same angle, more sunlight SL0 can be transmitted through the light-transmitting member 301 to the first solar cell module 31 than to the second solar cell module 32. For this reason, the conversion efficiency of the first solar cell module 31 may be higher than that of the second solar cell module 32. The conversion efficiency of the solar cell module 3 indicates the ratio of the energy of the light irradiated into the solar cell module 3 that is converted into electrical energy.

[0050] In the first embodiment, when the sun 900 performs its year-round diurnal motion, the estimated irradiance of the reflected light incident on one or more specific positions P1 in space, corresponding to the reflection of sunlight SL0 from multiple solar cell modules 3, is less than or equal to a predetermined irradiance. The one or more spaces may be the cockpit 5c of an aircraft 5 in flight, or the control room 6c of an air traffic control tower 6, as shown in Figures 2 and 6. The specific position P1 may be a specific position P1a in the cockpit 5c of an aircraft 5 in flight (also called the first specific position), or a specific position P1b in the control room 6c of an air traffic control tower 6 (also called the second specific position). Here, when the sun 900 performs its year-round diurnal motion, the statement that the estimated irradiance is less than or equal to a predetermined irradiance means that the state in which the estimated irradiance is less than or equal to a predetermined irradiance is maintained when the sun 900 performs its year-round diurnal motion.

[0051] Here, the predetermined irradiance is set to the irradiance at the boundary between the irradiance at which a person (also called the subject) does not feel dazzled by the reflected light of sunlight SL0 from the light-receiving surface 30s at a specific position P1, and the irradiance at which the subject feels dazzled by the reflected light of sunlight SL0 from the light-receiving surface 30s. The situation in which the subject feels dazzled by the reflected light of sunlight SL0 from the light-receiving surface 30s at a specific position P1 may include, for example, a situation in which the subject experiences a temporary afterimage (also called temporary flash blindness) due to the flash caused by the reflected light of sunlight SL0 from the light-receiving surface 30s at a specific position P1. The situation in which the subject does not feel dazzled by the reflected light of sunlight SL0 from the light-receiving surface 30s at a specific position P1 may include, for example, a situation in which the subject does not experience a temporary afterimage (temporary flash blindness) due to the flash caused by the reflected light of sunlight SL0 from the light-receiving surface 30s at a specific position P1. The persons at a specific location P1 may include, for example, one or more of the pilots in the cockpit 5c and the air traffic controllers in the control room 6c.

[0052] Here, let's assume a case where multiple solar cell modules 3 of a single type are installed on land along the longitudinal direction of runway 1 or landing strip 2 at airport 200. In this case, there may be specific plots of land where the orientation of the light-receiving surface 30s for obtaining high power generation in the multiple solar cell modules 3 coincides with the orientation of the light-receiving surface 30s at a specific location P1 in which a person will feel dazzled by the reflected sunlight SL0 from the light-receiving surface 30s. In other words, there may be specific plots of land where the orientation of the light-receiving surface 30s for obtaining high power generation in the multiple solar cell modules 3 does not coincide with the orientation of the light-receiving surface 30s at a specific location P1 in which a person will not feel dazzled by the reflected sunlight SL0 from the light-receiving surface 30s. In contrast, the first embodiment employs a configuration in which two or more types of solar cell modules 3 with different light reflectivity at the light-receiving surface 30s are arranged, including a first solar cell module 31 and a second solar cell module 32. As a result, even if the orientation of the light-receiving surface 30s of each of the multiple solar cell modules 3 is set to an orientation that yields high power generation, by placing the second solar cell module 32 on a specific plot of land, the estimated irradiance of reflected light received by a person at a specific location P1 from one or more light-receiving surfaces 30s will be below a predetermined irradiance. Consequently, the degree to which a person at a specific location P1 perceives reflected light from sunlight SL0 from the light-receiving surfaces 30s as dazzling can be reduced to an acceptable level.

[0053] For example, in a solar power generation system 100, from the viewpoint of increasing power generation, it is desirable to install the first solar cell module 31 facing the direction in which the sun is directly overhead (also called the meridian direction). However, there may be certain locations P1 where the degree to which a person perceives the reflected sunlight SL0 from the light-receiving surface 30s of the first solar cell module 31 as dazzling exceeds an acceptable range. In this case, one could consider changing the orientation of the light-receiving surface 30s of the first solar cell module 31 to face east or west, but this would lead to a decrease in the power generation of the solar power generation system 100. In contrast, in certain locations, for example, by using a second solar cell module 32 with a lower light reflectivity on its light-receiving surface 30s than the first solar cell module 31, and installing it with its light-receiving surface 30s facing the meridian direction, it is possible to keep the degree to which a person perceives the reflected sunlight SL0 from the light-receiving surface 30s of the second solar cell module 32 as dazzling within an acceptable range. Furthermore, in this case, it is possible to increase the amount of power generated in the photovoltaic power generation system 100 compared to, for example, a configuration in which the light-receiving surface 30s of the first solar cell module 31 is oriented eastward or westward on a specific plot of land. Also, in this case, it is possible to increase the amount of power generated in the photovoltaic power generation system 100 compared to a configuration in which all of the multiple solar cell modules 3 in the photovoltaic power generation system 100 are configured as multiple second solar cell modules 32, and the light-receiving surface 30s of each of the multiple second solar cell modules 32 are oriented toward the center.

[0054] Therefore, in the first embodiment, the glare caused by the reflection of sunlight SL0 can be reduced in the photovoltaic power generation system 100. From another perspective, the photovoltaic power generation system 100 can reduce the glare caused by the reflection of sunlight SL0 while reducing the decrease in power generation.

[0055] Here, as shown in Figure 6, if one or more spaces including a specific position P1 include the cockpit 5c of an aircraft 5 in flight, the aircraft 5 in flight may be, for example, an aircraft 5 in landing approach for landing on runway 1. In this case, the glare to the pilot from reflected sunlight SL0 on each light-receiving surface 30s of the multiple solar cell modules 3 can be reduced immediately before landing on runway 1, where piloting the aircraft 5 requires special attention.

[0056] Here, the aircraft 5 in landing approach may be the aircraft 5 with its landing gear lowered. For example, as shown in Figure 6, let Ln0 be the reference virtual line, which is a virtual straight line extending along the path (also called the landing flight path) that the aircraft 5 in landing approach takes to fly toward runway 1. In Figure 6, the reference virtual line Ln0 is shown as a straight line drawn with a thin dashed line. The aircraft 5 in landing approach flies along the reference virtual line Ln0 which is along the landing flight path. More specifically, the landing flight path is the path that the aircraft 5 takes toward the point Pc0 which is the centroid of the target point marker 1a on runway 1 (also called the landing reference point). The centroid may be the point where the first moment of area of ​​a figure is zero (0). In the first embodiment, if the target point marker 1a is a figure with uniform weight, the position corresponding to the center of gravity of the target point marker 1a may be considered as the centroid of the target point marker 1a. The landing flight path forms an inclination angle of a predetermined angle (also called the landing angle) with respect to the horizontal plane. The landing angle is set by the International Civil Aviation Organization (ICAO) to 3 degrees or an angle of approximately 3 degrees. An angle of approximately 3 degrees includes, for example, angles in the range of 2.5 to 3.5 degrees. Furthermore, the reference virtual line Ln0 is located along a virtual vertical plane (also called a virtual vertical plane) that passes through the runway centerline marker 1c of runway 1. The virtual vertical plane is a virtual plane that passes over the runway centerline marker 1c and is perpendicular to the horizontal plane. In other words, the reference virtual line Ln0 is located along the virtual vertical plane and has an inclination angle of 3 degrees or approximately 3 degrees with respect to runway 1, which is located along the horizontal plane. If the specific position P1 described above is the first specific position P1a, then the first specific position P1a may be any position along the reference virtual line Ln0.

[0057] Furthermore, the first specific position P1a here may be, for example, a viewpoint within the cockpit 5c. The viewpoint within the cockpit 5c may be, for example, a position from which an object including the target point marker 1a and the light-receiving surface 30s is viewed in an aircraft 5 in landing approach. Here, the viewpoint within the cockpit 5c may be specified by, for example, the position of the pilot's eyeballs, the position of the cockpit 5c, the position of the cockpit seat, or the position of the pilot's head. The position of the pilot's eyeballs may be a predetermined position of the eyeball (also called the first predetermined position), for example, the position of the approximate center of the retina of the eyeball in the pilot. The position of the cockpit 5c may be a predetermined position of the cockpit 5c (also called the second predetermined position), for example, the position of the approximate center of the cockpit 5c. The position of the cockpit seat may be a predetermined position of the cockpit seat (also called the third predetermined position), for example, the position of the approximate center of the cockpit seat headrest. For example, if there are multiple cockpits in the cockpit 5c, the position of a cockpit may be the designated position of the cockpit normally used by the pilot or captain (also called the principal pilot) who operates the aircraft 5 (the third designated position), or a designated position for multiple cockpits, such as the approximate center position between the multiple cockpits (also called the fourth designated position). The position of the pilot's head may be the designated position for the pilot's head, such as the approximate center position of the pilot's head (also called the fifth designated position). For example, if there are multiple pilots in the cockpit 5c, the position of the pilot's head may be the designated position for the principal pilot's head (the fifth designated position), or a designated position for multiple pilots' heads, such as the approximate center position between the heads of multiple pilots (also called the sixth designated position).

[0058] Here, if one or more spaces containing a specific position P1 include the control room 6c of the control tower 6, then the specific position (second specific position) P1b in the control room 6c of the control tower 6 may be the viewpoint of an air traffic controller. The viewpoint of an air traffic controller may be that of an air traffic controller seated at the control clearance transmission desk, or that of an air traffic controller seated at the ground control desk, or that of an air traffic controller seated at the airport control desk. In this case, the glare of the air traffic controller from reflected sunlight SL0 on each light-receiving surface 30s of the multiple solar cell modules 3 in the control room 6c of the airport 200 can be reduced. As a result, the ease with which air traffic controllers can guide aircraft 5 can be improved.

[0059] Here, the air traffic controller seated at the control clearance transmission station has a role such as relaying control clearances. The air traffic controller seated at the ground control station has a role such as issuing instructions regarding the movement of aircraft 5 on the ground other than runway 1. The air traffic controller seated at the airport control station has a role such as issuing instructions to aircraft 5 regarding takeoff and landing clearance, clearance to cross runway 1, and instructions regarding flight within the controlled area.

[0060] Furthermore, the second specific position P1b may be a viewpoint within the control room 6c. The viewpoint within the control room 6c may be the position from which the controller views an object including the light-receiving surface 30s, depending on their role. Here, the viewpoint within the control room 6c may be specified, for example, by the position of the controller's eyeballs, the position of the control room 6c, the position of the control seat, or the position of the controller's head. The position of the controller's eyeballs may be a predetermined position of the eyeball (also called the seventh predetermined position), for example, the approximate center of the retina of the controller's eyeball or the approximate center of the eyeball. The position of the control room 6c may be a predetermined position within the control room 6c (also called the eighth predetermined position), for example, the approximate center of the control room 6c. The control seat may be any of the control clearance transmission seats, ground control seats, and aerodrome control seats. The position of the control seat may be determined by a predetermined position of the control seat (also known as the 9th predetermined position), such as the approximate center position of the control seat's headrest. For example, if there are multiple control seats in control room 6c, the position of the control seat may be determined by the predetermined position of each of the multiple control seats (the 9th predetermined position), or by a predetermined position for multiple control seats (also known as the 10th predetermined position), such as the approximate center position between the multiple control seats. The position of the controller's head may be determined by a predetermined position for the controller's head (also known as the 11th predetermined position), such as the approximate center position of the controller's head. For example, if there are multiple controllers in control room 6c, the position of the controller's head may be determined by the predetermined position of each of the multiple controllers' heads (the 11th predetermined position), or by a predetermined position for multiple controllers' heads (also known as the 12th predetermined position), such as the approximate center position between the multiple controllers' heads.

[0061] <1-3. Reflection of sunlight in multiple solar cell modules> For example, as shown in Figure 7, on multiple light-receiving surfaces 30s of multiple solar cell modules 3, at least a portion of the irradiated sunlight SL0 from the sun 900 undergoes specular reflection. Then, for example, the light RL1 produced by specular reflection (also called specularly reflected light) may be incident on the subject's eyeball 7e at a specific position P1.

[0062] In Figure 7, the multiple light-receiving surfaces 30s are conveniently shown as a single elliptical region. In Figure 7, among the multiple light-receiving surfaces 30s, the region (also called the first reflection region) Ar1 that emits specularly reflected light RL1 corresponding to sunlight SL0 toward the subject's eyeball 7e at a specific position P1 is also conveniently shown as a single elliptical region. In Figure 7, the optical path of sunlight SL0 is drawn with a thin dashed line. In Figure 7, the normal 30n of the light-receiving surface 30s is shown with a thin solid line. In Figure 7, the outer edge of the first reflection region Ar1 is shown with a thin dashed ellipse. In Figure 7, the optical path of specularly reflected light RL1 toward the subject's eyeball 7e at a specific position P1 is drawn with a thin double-dotted line. In Figure 7, the angle (also called the incident angle) formed by the direction (also called the incident direction) in which sunlight SL0 enters the light-receiving surface 30s with respect to the normal 30n of the light-receiving surface 30s is shown as angle θ. The incident direction of sunlight SL0 is the direction of propagation of sunlight SL0 as incident light incident on the light-receiving surface 30s. From another perspective, the incident angle θ is the angle between the incident light ray and the normal 30n of the light-receiving surface 30s. The incident light ray may be an imaginary line along the direction of propagation of the incident light. In Figure 7, the angle (also called the line of sight angle) that the line of sight of the subject at a specific position P1 makes with respect to the normal 30n of the light-receiving surface 30s is shown by angle φ. In one example in Figure 7, the line of sight angle φ is the same as the incident angle θ.

[0063] The multiple light-receiving surfaces 30s are generally neither specular surfaces that produce only specular reflection nor surfaces that produce only diffuse reflection (also called perfectly diffuse reflective surfaces). In other words, the multiple light-receiving surfaces 30s are generally reflective surfaces (also called non-uniform diffuse reflective surfaces) in which the brightness of the reflected light is high when reflected in the direction that produces ideal specular reflection (also called the first reflection direction), and decreases as the reflected light deviates from the first reflection direction. Here, the direction in which ideal specular reflection occurs on the light-receiving surface 30s (the first reflection direction) is the direction in which specular reflection occurs on this specular surface, assuming the light-receiving surface 30s is a mirror.

[0064] If the light-receiving surface 30s is a typical glossy reflective surface (non-uniform diffuse reflective surface), then in response to the incidence of sunlight SL0 onto the light-receiving surface 30s, the light-receiving surface 30s will produce reflected light including specular reflection and diffuse reflection. In this case, for example, as shown in Figure 8, when sunlight SL0 is incident on point P0 of the light-receiving surface 30s, the brightness of the reflected light produced on the light-receiving surface 30s in response to the irradiation of sunlight SL0 shows a distribution drawn by the dashed line Lr with point P0 as the reference point. In the example shown in Figure 8, similar to the example in Figure 7, the angle between the direction of incidence of sunlight SL0 and the normal 30n of the light-receiving surface 30s is the incidence angle θ. The distribution drawn by the dashed line Lr with point P0 as the reference point changes depending on the angle (also called the reflection angle) θr between the normal 30n of the light-receiving surface 30s and the reflected light rays. Furthermore, if the light-receiving surface 30s is a non-uniform diffuse reflecting surface, the direction in which the light-receiving surface 30s actually emits specularly reflected light (also called the second reflection direction) includes the direction that produces ideal specular reflection (first reflection direction) and directions that are somewhat dispersed with the first reflection direction as the center or approximately center. For this reason, when the reflection angle θr is close to the incident angle θ, the brightness of the reflected light is higher compared to when the reflection angle θr is not close to the incident angle θ. More specifically, when the reflection angle θr is close to the incident angle θ, the brightness of the reflected light increases as the reflection angle θr approaches the incident angle θ. Therefore, the specularly reflected light RL1 corresponding to the sunlight SL0 emitted by the first reflection region Ar1 of the multiple light-receiving surfaces 30s toward the subject's eyeball 7e at a specific position P1 can be considered to include not only specularly reflected light toward the first reflection direction, but also specularly reflected light toward the second reflection direction, which includes the first reflection direction.

[0065] Here, as shown in Figure 8, the brightness of the reflected light produced at the light-receiving surface 30s is maximum when the reflection angle θr is the same as the incident angle θ. In other words, the intensity of the reflected light produced at the light-receiving surface 30s is maximum (also called peak intensity) when the reflection angle θr is the same as the incident angle θ. When the reflection angle θr is the same as the incident angle θ, the reflected light at reflection angle θr is the reflected light that is reflected in the direction that produces ideal specular reflection at the light-receiving surface 30s (first reflection direction). In other words, the first reflection direction that produces ideal specular reflection is the direction in which the reflected light propagates when the incident angle θ of sunlight SL0 with respect to the light-receiving surface 30s is the same as the reflection angle θr of the reflected light produced at the light-receiving surface 30s. Furthermore, as the reflection angle θr moves away from the incident angle θ, the brightness of the reflected light decreases. In other words, as the reflection angle θr moves away from the incident angle θ, the intensity of the reflected light produced at the light-receiving surface 30s decreases. Therefore, for example, if the subject's line of sight angle φ at a specific position P1 is close to the incident angle θ, the irradiance of the reflected light incident on the retina 7e5 of the subject's eyeball 7e at that specific position P1 may increase in response to the reflection of sunlight SL0 on the light-receiving surface 30s.

[0066] From another perspective, for example, the reflected light generated at the light-receiving surface 30s in response to irradiation with sunlight SL0 includes reflected light with a peak intensity generated by specular reflection of sunlight SL0 (also called first reflected light), reflected light generated by diffuse reflection of sunlight SL0 (also called diffuse reflected light), and reflected light generated by a slight dispersion in the specular reflection direction (also called second reflected light). The first reflected light corresponds to the reflected light reflected toward the first reflection direction that produces ideal specular reflection. The second reflected light may have an intensity of a predetermined intensity Th1 or greater, which is closer to the peak intensity of the first reflected light than the intensity of the diffuse reflected light. Here, the specular reflected light RL1 emitted by the first reflection region Ar1 among the multiple light-receiving surfaces 30s toward the eyeball 7e of the subject at a specific position P1, in response to sunlight SL0, may be reflected light that includes the first reflected light and the second reflected light. The predetermined intensity Th1 may be, for example, an intensity that is a predetermined ratio of the peak intensity. The predetermined percentage may be, for example, 90 percent (%), 50%, 25%, or any percentage in the range of 25% to 95%. Here, for example, as shown in Figure 8, if the reflection angle θr is within the angular range of angle β with the incident angle θ approximately centered, and the reflected light generated at the light-receiving surface 30s has a predetermined intensity Th1 or higher, then this angle β may be called the dispersion angle in the specular reflection direction.

[0067] Here, as shown in Figure 9, let ω [in radians (rad)] be the visual angle for the first reflection region Ar1 on the eyeball 7e of a subject at a specific position P1. The visual angle ω is the angle formed by the first reflection region Ar1 as a visual object projected onto the retina 7e5 of the subject's eyeball 7e at a specific position P1. From another perspective, the visual angle ω corresponds to the angle formed by two straight lines that pass through both ends of the first reflection region Ar1 as a visual object projected onto the retina 7e5 of the subject's eyeball 7e at a specific position P1, and extend to the eyeball 7e.

[0068] Figure 9 schematically shows the structure of the eyeball 7e. The eyeball 7e has a cornea 7e1, iris 7e2, lens 7e3, pupil 7e4, and retina 7e5. Figure 9 shows the distance x from the first reflection region Ar1 to the eyeball 7e, the focal length f of the eyeball 7e, the node 7e6 of the optical path from the first reflection region Ar1 to the retina 7e5, the width ds of the first reflection region Ar1 as seen from the subject at a specific position P1, the width dr of the area on the retina 7e5 where reflected light from the first reflection region Ar1 is projected, and the diameter (also called pupil diameter) dp of the pupil. The width ds is the width of the first reflection region Ar1 projected onto a plane perpendicular to the subject's line of sight at a specific position P1. The width ds may be, for example, the width of the first reflective region Ar1 when the first reflective region Ar1 projected onto a plane perpendicular to the line of sight of the subject at a specific position P1 is conveniently assumed to be a perfect circle, or it may be the width of the first reflective region Ar1 when the first reflective region Ar1 projected onto a plane perpendicular to the line of sight of the subject at a specific position P1 is conveniently assumed to be a square. Here, if the first reflective region Ar1 is inclined with respect to the line of sight of the subject at a specific position P1, then, for example, the distance x may be the distance from the centroid of the first reflective region Ar1 to the eyeball 7e, or it may be the average value of the distance from the first reflective region Ar1 to the eyeball 7e. The width ds of the first reflective region Ar1 may be calculated by various methods, for example. For example, if the first reflective region Ar1 is composed of the light-receiving surfaces 30s of two or more solar cell modules 3, then the first reflective region Ar1 may be a region that approximately includes the region located between the two or more solar cell modules 3. Furthermore, for example, if the first reflection region Ar1 is composed of two or more solar cell modules 3, the first reflection region Ar1 may be defined as the region excluding the region located between the two or more solar cell modules 3. In this case, for example, the width ds of the first reflection region Ar1 may be calculated as the width of the single region as seen from a subject at a specific position P1, after the first reflection region Ar1 has been converted into a single region excluding the region located between the two or more solar cell modules 3.

[0069] Here, for example, the estimated irradiance E1 is the estimated value of the irradiance of reflected light incident on the retina 7e5 of the subject's eyeball 7e at a specific position P1, in response to the reflection of sunlight SL0 on multiple light-receiving surfaces 30s of multiple solar cell modules 3. In this case, for example, when the sun 900 performs its annual diurnal motion, the estimated irradiance E1 becomes a critical irradiance Et [unit is watts per square meter (W / m)]. 2 )] or less is acceptable.

[0070] The critical irradiance Et can be calculated, for example, by equation (1), using the visual angle ω [rad] for the first reflection region Ar1 at the eyeball 7e of a subject at a specific position P1.

[0071] Et = 0.359 / ω 1.77 ...(1).

[0072] The critical irradiance Et defined by equation (1) corresponds to Eq. (5), which defines the green line in Fig. 2 of Non-Patent Literature 1 (Clifford K. Ho, Cheryl M. Ghanbari, Richard B. Diver, "Methodology to Assess Potential Glint and Glare Hazards From Concentrating Solar Power Plants: Analytical Models and Experimental Validation", Journal of Solar Energy Engineering, AUGUST 2011, Vol. 133 / 031021-1 to 031021-9). Non-Patent Literature 1 states that if the irradiance of light incident on the retina from the light source is less than the irradiance calculated by Eq. (5), the likelihood of the observer experiencing temporary afterimages due to flash (also known as temporary flash blindness) is low.

[0073] Therefore, for example, when the sun 900 performs its annual diurnal motion, if the estimated irradiance E1 is less than or equal to the critical irradiance Et calculated by equation (1), the glare caused by the reflection of sunlight SL0 in the photovoltaic power generation system 100 can be reduced.

[0074] <1-4. Method for Calculating Estimated Irradiance and Visual Angle> The estimated irradiance E1 and the viewing angle ω can each be calculated, for example, by various calculation methods. Here, we will describe an example of a method for calculating the estimated irradiance E1 and the viewing angle ω.

[0075] The estimated irradiance of specularly reflected light RL1 incident on the retina 7e5 of the subject's eyeball 7e at a specific position P1 is called retinal irradiance, Er [unit: W / m]. 2 Let Ec be defined as follows: Retinal irradiance Er corresponds to estimated irradiance E1. The irradiance of specularly reflected light RL1 incident on the cornea 7e1 of the subject's eyeball 7e at a specific position P1 (also called anterior corneal irradiance) is defined as Ec [unit: W / m 2 Let ] be the angle (angle of incidence) that the incident direction of sunlight SL0 makes with respect to the normal 30n of the light-receiving surface 30s is θ [unit: degrees (°)]. Let ρ(θ) [unit: %] be the specular reflectance in the first reflection region Ar1. Let E be the irradiance of sunlight SL0 incident perpendicular to the plane. DNI [Units are W / m] 2 Let's assume that the solar irradiance E DNI 1000W / m 2Let the pupil diameter be a constant value of 0.002m. Let the pupil diameter be a constant value of 0.002m. Let the light transmittance (light transmittance of the eyeball medium) be τ in the light path from the front surface of the cornea 7e1 to the retina 7e5 in the subject's eyeball 7e at a specific position P1. Let the transmittance τ be a constant value of 0.5. Let the focal length of the subject's eyeball 7e at a specific position P1 be f [in meters]. Let the focal length f be a constant value of 0.017m. Let the dispersion angle for the specular reflection direction described above be β [in rad]. As described above, let the angle (line of sight angle) of the subject's line of sight at a specific position P1 be φ [in degrees (°)] with respect to the normal 30n of the light-receiving surface 30s. Here, the subject's line of sight may be assumed to pass through representative points related to multiple light-receiving surfaces 30s. As described above, the visual angle related to the first reflection region Ar1 on the subject's eyeball 7e at a specific position P1 is ω [unit: rad]. The width of the light image of the first reflection region Ar1 projected onto the retina 7e5 of the subject's eyeball 7e at the specific position P1 (also called the retinal projection image width) is dr [unit: m]. Here, the first reflection region Ar1 as seen from the subject at the specific position P1 may be considered a perfect circle, and the apparent diameter of the light image of the first reflection region Ar1 may be taken as dr [m]. The width of the first reflection region Ar1 as seen from the subject at the specific position P1 may be ds [unit: m]. Here, the first reflection region Ar1 as seen from the subject at the specific position P1 may be considered a perfect circle, and the apparent diameter of the first reflection region Ar1 may be taken as ds [m]. The area of ​​the first reflection region Ar1 is Ah [unit: m]. Let x [in meters] be the distance from the light-receiving surface 30s to the subject at a specific position P1. Here, the distance x may be the distance between a representative point related to multiple light-receiving surfaces 30s and the specific position P1. Regarding the line-of-sight angle φ and distance x, for example, the estimated irradiance E1 and viewing angle ω are calculated for each module group 3g, and the representative point related to multiple light-receiving surfaces 30s may be the representative point of the module group 3g. For example, the centroid of the module group 3g viewed from a plan may be applied to the representative point of the module group 3g. Also, the representative point related to multiple light-receiving surfaces 30s may be the representative point of the first reflection region Ar1.In this case, for example, the centroid of the first reflection area Ar1 may be applied as the representative point of the first reflection area Ar1.

[0076] In this case, formulas (2-1) to (2-6) can be established.

[0077] ω=β×{2x×tan(β / 2) / ds} -1 ···(2-1) ds={(4Ah×cosφ) / π} 0.5 ···(2-2) Ec=ρ(θ)×E DNI ×C ···(2-3) C={2x×tan(β / 2) / ds} -2 ···(2-4) dr=f×ω ···(2-5) Er=Ec×{(π×dp 2 / 4) / (π×dr 2 / 4)}×τ =Ec×(dp 2 / dr 2 )×τ ···(2-6).

[0078] By substituting formulas (2-3), (2-4), (2-5) and (2-1) into formula (2-6), formula (2-7) can be obtained.

[0079] Er={ρ(θ)×E DNI ×dp 2 ×τ} / (f 2 ×β 2 ) ···(2-7).

[0080] Retinal irradiance Er corresponding to the estimated irradiance E1 can be calculated using formula (2-7).

[0081] Here, the solar irradiance E DNIBy applying known values ​​to the pupil diameter dp, light transmittance τ, and focal length f, the retinal irradiance Er can be calculated using the incident angle θ, specular reflectance ρ(θ), and dispersion angle β. In this case, the estimated irradiance E1 is the retinal irradiance Er, which is an estimate of the irradiance of specularly reflected light RL1 that occurs when sunlight SL0 undergoes specular reflection in the first reflection region Ar1 and is incident on the subject's retina 7e5 at a specific position P1.

[0082] Here, the incident angle θ is calculated based, for example, on the altitude (also called solar altitude) and azimuth angle (also called solar azimuth angle) of the sun at 900°, and the direction in which the light-receiving surface 30s is facing. The direction in which the light-receiving surface 30s is facing is defined, for example, by the angle between the normal 30n of the light-receiving surface 30s and the horizontal plane (also called the installation angle) [unit: degrees (°)] and the angle between the normal direction of the light-receiving surface 30s and the north direction when viewed from above (also called the installation direction) [unit: degrees (°)]. In this disclosure, the installation direction is indicated by the angle by which the normal direction of the light-receiving surface 30s rotates clockwise from the north direction when viewed from above, with the north direction being the reference 0 degrees. For example, if the normal direction of the light-receiving surface 30s is east when viewed from above, the installation direction is 90 degrees. If the normal direction of the light-receiving surface 30s is south when viewed from above, the installation direction is 180 degrees. If the normal direction of the light-receiving surface 30s is west when viewed from above, the installation orientation is 270 degrees. The specular reflectance ρ(θ) is a variable that changes depending on the incident angle θ. This specular reflectance ρ(θ) can be obtained, for example, by measuring the relationship between the incident angle θ[°] and the reflectance (solar reflectance[%]) using a measuring device such as a gloss meter, in accordance with the "Specular gloss - Measurement method" specified in Japanese Industrial Standard (JIS) Z8741. The dispersion angle β can be calculated, for example, from the measurement results using a bending-angle photometer or bending-angle gloss meter.

[0083] Furthermore, the visual angle ω is calculated here using the equation obtained by substituting equation (2-2) into equation (2-1), along with the dispersion angle β, distance x, area Ah, and line-of-sight angle φ.

[0084] Here, the dispersion angle β is obtained, as described above, for example, from the results of measurements using a variable-angle photometer or variable-angle glossometer. The distance x is calculated, for example, according to the positions of the representative point and the specific position P1 related to the multiple light-receiving surfaces 30s. The area Ah is calculated, for example, from the relationship between the altitude (solar altitude) and azimuth angle (solar azimuth angle) of the sun 900, the positions of the multiple light-receiving surfaces 30s, the direction in which the light-receiving surfaces 30s are facing, and the position of the specific position P1. The line-of-sight angle φ is calculated, for example, according to the position of the representative point related to the multiple light-receiving surfaces 30s, the direction in which the light-receiving surfaces 30s are facing, and the position of the specific position P1.

[0085] Then, by substituting the calculated viewing angle ω into equation (1), the critical irradiance Et can be calculated.

[0086] <1-5. Setting up multiple solar modules> Here, for example, let's consider a case where each of the multiple solar cell modules 3 is virtually designated as a first solar cell module 31, as shown in Figures 10 and 11. In this case, it is conceivable that each of the one or more solar cell modules 3 among the multiple solar cell modules 3 that causes the estimated value of the irradiance of the reflected light incident on a specific position P1 in response to the reflection of sunlight SL0 (estimated irradiance) to be greater than a predetermined irradiance is actually a second solar cell module 32. This makes it possible to reduce the decrease in power generation in the photovoltaic power generation system 100 by, for example, arranging a larger number of first solar cell modules 31 and a smaller number of second solar cell modules 32. Here, when each of the multiple solar cell modules 3 is virtually designated as a first solar cell module 31, it is also possible to virtually designate each of the light-receiving surfaces 30s of the multiple solar cell modules 3 as a first light-receiving surface 30s1.

[0087] <<Evaluation of Estimated Irradiance>> Here, we will explain a method for evaluating whether the retinal irradiance Er, which corresponds to the estimated irradiance E1, is greater than the critical irradiance Et, which is a predetermined irradiance, when each of the multiple solar cell modules 3 is virtually designated as the first solar cell module 31. Here, we will explain by giving an example of calculating the retinal irradiance Er, which corresponds to the estimated irradiance E1, and the critical irradiance Et, which is a predetermined irradiance, for each module group 3g.

[0088] Figure 12 is a flowchart showing an example of a flow chart for determining the relationship between the apparent angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its annual diurnal motion. This flow chart can be executed on a computer or similar device.

[0089] In step St1 of Figure 12, the time is set to the time of sunrise on January 1st. Here, the solar altitude and solar azimuth of Sun 900 are set according to the set time.

[0090] Next, in step St2, it is determined whether a specific position P1 is located on the optical path of specularly reflected light RL1 of sunlight SL0 generated by multiple light-receiving surfaces 30s in module group 3g. If the specific position P1 is located on the optical path of specularly reflected light RL1, the process proceeds to step St3; otherwise, the process proceeds to step St4.

[0091] Figure 13 shows an example of the relationship between the optical path of specularly reflected light RL1 generated by irradiation with sunlight SL0 at multiple light-receiving surfaces 30s in the first group 3g1 and a specific position P1. In Figure 13, the multiple light-receiving surfaces 30s in the first group 3g1 are conveniently represented as a single light-receiving surface 30s. In Figure 13, the outer edge of the optical path of sunlight SL0 toward the light-receiving surface 30s (also called the first optical path) is indicated by a thin dashed-dotted arrow. The outer edge of the optical path R2 of specularly reflected light RL1 of sunlight SL0 generated at multiple light-receiving surfaces 30s (also called the second optical path) is indicated by a thin double-dotted arrow. The second optical path R2 includes the optical path R21 of specularly reflected sunlight SL0, which is directed toward the first reflection direction that produces ideal specular reflection on multiple light-receiving surfaces 30s (also called the second A optical path), and the optical path R22 of specularly reflected light that spreads according to the dispersion angle β on multiple light-receiving surfaces 30s (also called the second B optical path). In Figure 13, the boundary between the second A optical path R21 and the second B optical path R22 is indicated by a thin dashed line arrow. In Figure 13, the second A optical path R21 is hatched with an upward-sloping diagonal line, and the second B optical path R22 is hatched with a sandy pattern. In the example shown in Figure 13, when a specific position P1 is at position Pt1, the specific position P1 is located on the second optical path R2 of the specularly reflected light RL1, and when a specific position P1 is at position Pt2, the specific position P1 is not located on the second optical path R2 of the specularly reflected light RL1.

[0092] Next, in step St3, the visual angle ω [rad] for the first reflection region Ar1 at the subject's eyeball 7e at a specific position P1 is calculated, and the estimated irradiance E1 is the retinal irradiance Er [W / m], which is the estimated value of the irradiance of the specularly reflected light RL1 of sunlight SL0 generated in the first reflection region Ar1 that is incident on the retina 7e5 of the subject's eyeball 7e at a specific position P1. 2 The retinal irradiance Er[W / m] is calculated using the calculated visual angle ω[rad]. 2Points showing the relationship between [ ] are plotted on the graph. Here, the visual angle ω is calculated, for example, using the equation obtained by substituting equation (2-2) into equation (2-1) as described above, along with the dispersion angle β, distance x, area Ah, and line of sight angle φ. The retinal irradiance Er corresponding to the estimated irradiance E1 is calculated, for example, using equation (2-7) as described above. The visual angle ω [rad] and retinal irradiance Er [W / m 2 The relationship between ] is shown in Figure 14, with the horizontal axis representing the visual angle ω [rad] and the vertical axis representing the retinal irradiance Er [W / m 2 The graph in Figure 14 may be plotted using the following formula: The graph shows the viewing angle ω [rad] and critical irradiance Et [W / m²] defined by equation (1). 2 The relationship with ] is shown by the dashed line Lth. In the graph of Figure 14, the region of irradiance exceeding the dashed line Lth is hatched using a sand pattern.

[0093] Next, in step St4, it is determined whether the time is after sunset on December 31st. If the set time is not after sunset on December 31st, the process proceeds to step St5. If the set time is after sunset on December 31st, the flow shown in Figure 12 is terminated.

[0094] In step St5, the time is advanced by a predetermined amount of time, and the process returns to step St2. The predetermined amount of time may be, for example, one minute, or any other amount of time.

[0095] The flow chart shown in Figure 12 allows for the creation of a graph plotting points for one module group 3g, showing the relationship between the apparent angle ω related to the first reflection region Ar1 during the year-round diurnal motion of the sun 900 and the retinal irradiance Er corresponding to the estimated irradiance E1. This graph may be created for each of multiple module groups 3g.

[0096] Here, for the module group 3g among the multiple module groups 3g, where there are points plotted above the straight line Lth in the graph shown in Figure 14, if the first solar cell module 31 is applied to each of the two or more solar cell modules 3 constituting the module group 3g, there may be times when the retinal irradiance Er, as the estimated irradiance E1, becomes greater than the critical irradiance Et, which is a predetermined irradiance, as the sun 900 performs its diurnal motion throughout the year. This allows us to evaluate whether the retinal irradiance Er, corresponding to the estimated irradiance E1, becomes greater than the critical irradiance Et, which is a predetermined irradiance, for each module group 3g.

[0097] Incidentally, for example, during the design phase of the solar power generation system 100, a graph can be created for each module group 3g as described above, and for module groups 3g where a graph is obtained in which points are plotted above the straight line Lth, it is conceivable to apply the second solar cell module 32. In other words, for module groups 3g where a graph is obtained in which points are plotted above the straight line Lth, it is conceivable to apply the second group 3g2 instead of the first group 3g1. From another perspective, if each of the multiple solar cell modules 3 is virtually considered to be the first solar cell module 31, then it is possible to designate each of the one or more solar cell modules 3 among the multiple solar cell modules 3 that makes the estimated irradiance E1 of the reflected light incident at a specific position P1 in response to the reflection of sunlight SL0 greater than a predetermined irradiance as the second solar cell module 32. As a result, as shown by the thick dashed arrow in Figure 14, the retinal irradiance Er as the estimated irradiance E1 can be reduced to below the critical irradiance Et as irradiance. As a result, when the sun 900 performs its annual diurnal motion, it is possible to ensure that there is no time at a specific position P1 when the retinal irradiance Er, which is the estimated irradiance E1, exceeds the critical irradiance Et, which is a predetermined irradiance. Therefore, the glare caused by the reflection of sunlight SL0 in the photovoltaic power generation system 100 can be reduced.

[0098] Here, for example, a graph may be created for each of several module groups 3g, obtained by applying the second group 3g2 to some module groups 3g and the first group 3g1 to the remaining module groups 3g, following the flow shown in Figure 12, plotting points that show the relationship between the visual angle ω related to the first reflection region Ar1 when the sun 900 performs its year-round diurnal motion and the retinal irradiance Er as estimated irradiance E1. This allows us to confirm that the retinal irradiance Er as estimated irradiance E1 is reduced to below the critical irradiance Et.

[0099] In this case, a second solar cell module 32 may be applied to each of the solar cell modules 3 that make up a single module group 3g. In this case, the design and construction work of the photovoltaic power generation system 100 can be simplified.

[0100] <<Example of setting up multiple solar modules>> Here, for example, as shown in Figure 6, we assume that a plurality of module groups 3g include a group A 3ga, which is a module group 3g composed of a first number of solar cell modules 3, and a group B 3gb, which is a module group 3g composed of a second number of solar cell modules 3. The first number and the second number can each be any number of two or more. In this case, we further assume, for example, as shown in Figure 11, that each of the plurality of solar cell modules 3 is virtually designated as a first solar cell module 31. In other words, we assume that each of all solar cell modules 3 constituting group A 3ga is virtually designated as a first solar cell module 31, and each of all solar cell modules 3 constituting group B 3gb is virtually designated as a first solar cell module 31. Here, if each of all solar cell modules 3 constituting group A 3ga is virtually designated as a first solar cell module 31, then each of the light-receiving surfaces 30s of all solar cell modules 3 constituting group A 3ga may also be virtually designated as a first light-receiving surface 30s1. If each of the solar cell modules 3 constituting group B 3gb is virtually designated as the first solar cell module 31, then each of the light-receiving surfaces 30s of the solar cell modules 3 constituting group B 3gb may also be virtually designated as the first light-receiving surface 30s1.

[0101] In this case, for example, the estimated irradiance E1 of the reflected light incident on the retina 7e5 of the eyeball 7e at a specific position P1 at a visual angle (also called the first visual angle) ω1 [rad] in response to the reflection of sunlight SL0 in group A 3ga is the first estimated irradiance E11 [W / m 2]. More specifically, for example, in the first reflection region Ar1 of multiple light-receiving surfaces 30s in group A 3ga, when specular reflected light RL1 is generated toward a specific position P1 in response to irradiation by sunlight SL0, the visual angle ω of the first reflection region Ar1 at the eyeball 7e of the subject at the specific position P1 may be defined as the first visual angle ω1 [rad]. This first visual angle ω1 [rad] can be calculated, for example, by substituting equation (2-2) into equation (2-1) as described above, and using the dispersion angle β, distance x, area Ah, and line of sight angle φ. For example, in the first reflection region Ar1 of multiple light-receiving surfaces 30s in group A 3ga, when specular reflected light RL1 is generated toward a specific position P1 in response to irradiation by sunlight SL0, the retinal irradiance Er [W / m 2 The estimated irradiance E1 corresponding to ] is the first estimated irradiance E11 [W / m 2 This can be considered as follows: This first estimated irradiance E11 [W / m 2 ] can be calculated, for example, using equation (2-7) as described above.

[0102] Furthermore, for example, in group B 3gb, the estimated irradiance E1 of the reflected light incident on the retina 7e5 of the eyeball 7e at a specific position P1 at a visual angle (also called the second visual angle) ω2 [rad] in response to the reflection of sunlight SL0 is given by the second estimated irradiance E12 [W / m 2]. More specifically, for example, in the first reflection region Ar1 of multiple light-receiving surfaces 30s in group B 3gb, when specular reflected light RL1 is generated toward a specific position P1 in response to irradiation by sunlight SL0, the visual angle ω of the first reflection region Ar1 at the eyeball 7e of the subject at the specific position P1 may be defined as the second visual angle ω2 [rad]. This second visual angle ω2 [rad] can be calculated, for example, by substituting equation (2-2) into equation (2-1) as described above, and using the dispersion angle β, distance x, area Ah, and line of sight angle φ. For example, in the first reflection region Ar1 of multiple light-receiving surfaces 30s in group B 3gb, when specular reflected light RL1 is generated toward a specific position P1 in response to irradiation by sunlight SL0, the retinal irradiance Er [W / m 2 The estimated irradiance E1 corresponding to ] is the second estimated irradiance E12 [W / m 2 This can be considered as the second estimated irradiance E12 [W / m 2 ] can be calculated, for example, using equation (2-7) as described above.

[0103] Furthermore, the critical irradiance Et obtained by substituting the first viewing angle ω1 [rad] into equation (1) is given by the first critical irradiance Et1 [W / m 2 Let ]. In other words, using the first visual angle ω1 [rad], Et1 = 0.359 / ω1 1.77 The first critical irradiance, calculated using the formula Et1[W / m²], is defined as a predetermined irradiance. 2 ]

[0104] Furthermore, the critical irradiance Et obtained by substituting the second viewing angle ω² [rad] into equation (2) is the second critical irradiance Et² [W / m 2 Let ]. In other words, using the second visual angle ω² [rad], Et² = 0.359 / ω¹ 1.77 The second critical irradiance, calculated using the formula Et2[W / m²], is defined as a predetermined irradiance. 2 ]

[0105] In this case, for example, when the sun 900 performs its annual diurnal motion, if there is a time when the first estimated irradiance E11 exceeds the first critical irradiance Et1 and the second estimated irradiance E12 does not exceed the second critical irradiance Et2, then as shown in Figure 6, group A 3ga group may be group 2 3g2 and group B 3gb may be group 1 3g1. Also, for example, when the sun 900 performs its annual diurnal motion, if there is a time when the first estimated irradiance E11 exceeds the first critical irradiance Et1 and the second estimated irradiance E12 exceeds the second critical irradiance Et2, then group A 3ga group may be group 1 3g1 and group B 3gb may be group 2 3g2. With this configuration, for example, by arranging a larger number of first solar cell modules 31 and a smaller number of second solar cell modules 32, it is possible to reduce the decrease in power generation in the photovoltaic power generation system 100.

[0106] Furthermore, consider the case where, for example, when the sun 900 performs its annual diurnal motion, there is no time when the first estimated irradiance E11 exceeds the first critical irradiance Et1 and no time when the second estimated irradiance E12 exceeds the second critical irradiance Et2. In this case, for example, if the minimum value of the difference obtained by subtracting the first estimated irradiance E11 from the first critical irradiance Et1 (also called the first difference value) is smaller than the minimum value of the difference obtained by subtracting the second estimated irradiance E12 from the second critical irradiance Et2 (also called the second difference value), then, as shown in Figure 6, group A 3ga may be group 2 3g2 and group B 3ga may be group 1 3g1. Also, for example, if the minimum value of the first difference value is larger than the minimum value of the second difference value, then group A 3ga may be group 1 3g1 and group B 3gb may be group 2 3g2. This configuration allows for further reduction of glare caused by the reflection of sunlight SL0 from the solar power generation system 100.

[0107] Here, when the sun 900 performs its annual diurnal motion, the minimum value of the first difference is smaller than the minimum value of the second difference, which means that the difference between the first critical irradiance Et1 and the first estimated irradiance E11 at the time when the first estimated irradiance E11 is closest to the first critical irradiance Et1 is smaller than the difference between the second critical irradiance Et2 and the second estimated irradiance E12 at the time when the second estimated irradiance E12 is closest to the second critical irradiance Et2. Furthermore, when the sun 900 performs its annual diurnal motion, the minimum value of the first difference is greater than the minimum value of the second difference, which means that the difference between the first critical irradiance Et1 and the first estimated irradiance E11 at the time when the first estimated irradiance E11 is closest to the first critical irradiance Et1 is greater than the difference between the second critical irradiance Et2 and the second estimated irradiance E12 at the time when the second estimated irradiance E12 is closest to the second critical irradiance Et2.

[0108] <1-6. Specific examples of calculations related to estimated irradiance and power generation> <1-6-1. First calculation example> In the first calculation example, as shown in Figure 15, we assumed that runway 1 of airport 200 has a longitudinal direction along the direction from north-northwest to south-southeast. In this case, we assumed that two module groups 3g are located on the northeast side of runway 1. In Figure 15, each of the two module groups 3g is conveniently shown as a single rectangle. The two module groups 3g are designated as group A 3ga and group B 3gb, and it was assumed that group A 3ga and group B 3gb are arranged in this order along the direction from north-northwest to south-southeast. In other words, it was assumed that group A 3ga and group B 3gb are arranged along the longitudinal direction of runway 1 on land along the longitudinal direction of runway 1.

[0109] Here, we first designated Group A 3ga and Group B 3gb as Group 1 3g1. Specifically, each of the first number of solar cell modules 3 constituting Group A 3ga was designated as Group 1 solar cell module 31, and each of the second number of solar cell modules 3 constituting Group B 3gb was designated as Group 1 solar cell module 31. In Figure 15, Group 1 3g1 is hatched with an upward-sloping diagonal line.

[0110] The orientation of the first light-receiving surface 30s1 of the first solar cell module 31 was set to an installation angle of 15 degrees and an installation orientation of 180 degrees. The dispersion angle β on the first light-receiving surface 30s1 was set to 5 degrees, calculated from the measured results. The specular reflectance ρ(θ) on the first light-receiving surface 30s1 was the value measured using a measuring device. For example, for the first light-receiving surface 30s1, the specular reflectance ρ(85 degrees) was 60% when the incident angle θ of sunlight SL0 was 85 degrees. Furthermore, the condition was that a specific position P1 was a specific position (first specific position) P1a in the cockpit 5c of an aircraft 5 in landing approach.

[0111] Then, for group A3ga, following the flow shown in Figure 12, a graph was created in which points were plotted showing the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion. As a result, a graph was obtained in which points were plotted in the region Ae1 enclosed by a thick dashed line, as shown in Figure 16. More specifically, a graph was obtained in which points were plotted above the straight line Lth. From this graph, it was confirmed that for group A3ga, when the first solar cell module 31 is applied to each of the first number of solar cell modules 3 constituting group A3ga, there is a time when the retinal irradiance Er, as the estimated irradiance E1, is greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion. In other words, if group A 3ga is group 1 3g1, it was confirmed that the pilot, as the target at a first specific position P1a, can be dazzled by the specularly reflected light RL1 of sunlight SL0 generated in group A 3ga.

[0112] On the other hand, for group B 3gb, following the flow shown in Figure 12, a graph was created plotting points that show the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion. In this case, in the determination in step St2, there was no time when a specific position P1 was located on the optical path of the specularly reflected light RL1 of sunlight SL0 generated at multiple light-receiving surfaces 30s in group B 3gb when the sun 900 performs its year-round diurnal motion, and a graph was obtained in which no points were plotted at all. From this graph, it was confirmed that for group B 3gb, even if the first solar cell module 31 is applied to each of the second number of solar cell modules 3 constituting group B 3gb, there is no time when the retinal irradiance Er, as the estimated irradiance E1, is greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion.

[0113] Therefore, based on the configuration shown in Figure 15, group A 3ga was changed from group 1 3g1 to group 2 3g2, as shown in Figure 17. More specifically, each of the first number of solar cell modules 3 constituting group A 3ga was designated as a second solar cell module 32. In Figure 17, group 2 3g2 is hatched with a diagonal line rising to the left. The direction in which the second light-receiving surface 30s2 of the second solar cell module 32 faces was set to the same direction as the first light-receiving surface 30s1 of the first solar cell module 31, with an installation angle of 15 degrees and an installation orientation of 180 degrees. The dispersion angle β at the second light-receiving surface 30s2 was set to 57.3 degrees, calculated from the measured results. The specular reflectance ρ(θ) at the second light-receiving surface 30s2 was the value measured using a measuring device. For example, for the second light-receiving surface 30s2, the specular reflectance ρ(85 degrees) was 5% when the incident angle θ of sunlight SL0 was 85 degrees. Furthermore, the condition was that a specific position P1 was a specific position (first specific position) P1a in the cockpit 5c of an aircraft 5 in landing approach.

[0114] Then, for group A3ga, which was changed from group 13g1 to group 23g2, a graph was created plotting points showing the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion, following the flow shown in Figure 12. As a result, a graph was obtained in which points are plotted in the region Ae2 enclosed by a thick dashed line, as shown in Figure 18. More specifically, a graph was obtained in which points are plotted below the straight line Lth. From this graph, it was confirmed that for group A3ga, when the second solar cell module 32 is applied to each of the first number of solar cell modules 3 constituting group A3ga, there is no longer a time when the retinal irradiance Er, as the estimated irradiance E1, is greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion. In other words, it was confirmed that if group A 3ga is group 2 3g2, the occurrence of a situation in which the pilot, as the target person at the first specific position P1a, may be dazzled by the specularly reflected light RL1 of sunlight SL0 generated in group A 3ga can be reduced.

[0115] By the way, by changing the installation orientation while keeping group A 3ga as group 1 3g1, it is conceivable to create a configuration in which, when the sun 900 performs its yearly diurnal motion, there is no time when the retinal irradiance Er, which is the estimated irradiance E1, for group A 3ga exceeds the critical irradiance Et, which is the predetermined irradiance.

[0116] Here, let Ep [unit: megawatt-hours per year (MWh / year)] be the annual power generation of one module group 3g. Let Cp [unit: kilowatts (kW)] be the capacity (also called PV capacity) of one module group 3g. Let Hy [unit: kilowatt-hours per square meter per year (kWh / m)] be the total amount of monthly average daily cumulative solar radiation on a tilted surface over one year. 2 ( / year)

[0117] Furthermore, let's consider a case where, in a single module group 3g, n (n is a natural number) solar cell modules 3 are fixed to each of the multiple mounting frames 4 arranged in a matrix. In this case, one unit (also called a module unit) 3u is composed of n solar cell modules 3. In other words, a module unit 3u is fixed to each of the multiple mounting frames 4 arranged in a matrix. From another perspective, multiple module units 3u are arranged in a matrix. Moreover, let's consider a case where, as shown in Figure 19, a single module group 3g has multiple module unit rows 3ar. Here, a module unit row 3ar consists of two or more module units 3u arranged at a first array pitch L1 [unit is meters (m)] in a first horizontal direction Dr1 along the x-direction. Multiple module unit rows 3ar are arranged at a second array pitch L2 [unit is meters (m)] in a second horizontal direction Dr2 orthogonal to the first horizontal direction Dr1. In the example shown in Figure 19, the number of solar cell modules 3 constituting one module unit 3u (also called the number of rows), n, is 2. The first array pitch L1 may also be called the distance between modules, and the second array pitch L2 may also be called the distance between arrays. Here, the second array pitch L2 is set to a length such that the shadow of one module unit row 3ar does not fall on another module unit row 3ar at 9 a.m. and 3 p.m. on the summer solstice, 9 a.m. and 3 p.m. on the winter solstice.

[0118] Furthermore, let P [watts per module (W / module)] be the output of one solar cell module 3. When viewed from above, let A [square meters (m)] be the area of ​​land on which one module group 3g is installed (also called the installation area). 2 )]. The module output P [W / unit] is calculated using a solar simulator in accordance with the provisions of Japanese Industrial Standard (JIS) C8904-3, assuming an air mass (AM) of 1.5 and an irradiance of 1000 W / m² as defined in Japanese Industrial Standard (JIS) C8918. 2 (=1kW / m 2This is obtained by taking measurements under the condition that the temperature of the solar cell module 3 is 25 degrees Celsius (25°C). In other words, the module output P [W / unit] is 1 kW / m² on the light-receiving surface 30s of one solar cell module 3. 2 This is the output when irradiated with light of that irradiance.

[0119] The PV capacity Cp [kW] is calculated using equation (3-1).

[0120] Cp=P×(n×A) / (L1×L2) ···(3-1).

[0121] The total amount of average daily cumulative solar radiation on an inclined surface over one year: Hy[kWh / m 2 The value [ / year] is obtained by using the installation angle and orientation that define the direction in which the light-receiving surface 30s is facing, in accordance with Annex 1 of the Japanese Industrial Standard (JIS) C8907.

[0122] The annual power generation Ep [MWh / year] for one module group 3g is calculated using equation (3-2).

[0123] Ep = Cp / 1 [kW / m 2 ] × Hy ···(3-2).

[0124] Here, based on the configuration shown in Figure 15, if the installation orientation is changed from 180 degrees to 140 degrees while keeping Group A 3ga as Group 1 3g1, the annual power generation Ep for Group A 3ga was calculated to be "13234 [MWh / year]". Here, the first array pitch L1 is 1.742 [m], the second array pitch L2 is 8.3 [m], the number of stages n is 4 [units], and the installation area A is 59700 [m²]. 2 The module output P was set to 545 [W / unit] as an actual measured value. In addition, the total amount Hy of the monthly average daily cumulative solar radiation on an inclined surface for one year was calculated to be 1469 [kWh / m²] under the conditions that the installation angle is 15 degrees and the installation orientation is 140 degrees. 2 [ / year]

[0125] In contrast, when the configuration shown in Figure 15 was used as a base and the group A 3ga was changed from the first group 3g1 to the second group 3g2 as shown in Figure 17, the annual power generation Ep for group A 3ga was calculated to be "15032 [MWh / year]". Here, each of the first number of solar cell modules 3 constituting group A 3ga was designated as the second solar cell module 32, the first array pitch L1 was set to 1.742 [m], the second array pitch L2 was set to 7.3 [m], the number of stages n was set to 4 [units], and the installation area A was set to 59700 [m²]. 2 The module output P was set to 530 [W / unit] as an actual measured value. In addition, the total amount Hy of the monthly average daily cumulative solar radiation on an inclined surface for one year was calculated to be 1504 [kWh / m²] under the conditions that the installation angle is 15 degrees and the installation orientation is 180 degrees. 2 [ / year]

[0126] From the calculation results above, it was confirmed that the annual power generation Ep for group A 3ga is greater when group A 3ga is changed from group 1 3g1 to group 2 3g2 compared to when group A 3ga remains group 1 3g1 but the installation orientation is changed from 180 degrees to 140 degrees.

[0127] Therefore, it was confirmed that by using group 3g2 instead of group 3g1 for group A 3ga, it is possible to reduce glare caused by reflection of sunlight SL0 while also reducing the decrease in power generation.

[0128] <<Second calculation example>> In the second calculation example, as shown in Figure 20, we assumed that runway 1 of airport 200 has a longitudinal direction along the east-west direction. In this case, we assumed that group A 3ga, as one module group 3g, is located on the land north of runway 1 along the longitudinal direction of runway 1, and group B 3gb, as another module group 3g, is located on the land south of runway 1 along the longitudinal direction of runway 1. In Figure 20, each of the two module groups 3g is conveniently shown as a single rectangle.

[0129] Here, we first designated Group A 3ga and Group B 3gb as Group 1 3g1. Specifically, each of the first number of solar cell modules 3 constituting Group A 3ga was designated as Group 1 solar cell module 31, and each of the second number of solar cell modules 3 constituting Group B 3gb was designated as Group 1 solar cell module 31. In Figure 20, Group 1 3g1 is hatched with an upward-sloping diagonal line.

[0130] The orientation of the first light-receiving surface 30s1 of the first solar cell module 31 was set to an installation angle of 20 degrees and an installation orientation of 180 degrees. The dispersion angle β on the first light-receiving surface 30s1 was set to 5 degrees, calculated from the measured results. The specular reflectance ρ(θ) on the first light-receiving surface 30s1 was the value measured using a measuring device. For example, for the first light-receiving surface 30s1, the specular reflectance ρ(85 degrees) was 60% when the incident angle θ of sunlight SL0 was 85 degrees. Furthermore, the condition was that a specific position P1 was a specific position (first specific position) P1a in the cockpit 5c of an aircraft 5 in landing approach.

[0131] Then, for group A3ga, following the flow shown in Figure 12, a graph was created in which points were plotted showing the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion. As a result, a graph was obtained in which points were plotted in the region Ae3 enclosed by a thick dashed line, as shown in Figure 21. More specifically, a graph was obtained in which points were plotted above the straight line Lth. From this graph, it was confirmed that for group A3ga, when the first solar cell module 31 is applied to each of the first number of solar cell modules 3 constituting group A3ga, there is a time when the retinal irradiance Er, as the estimated irradiance E1, is greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion. In other words, if group A 3ga is group 1 3g1, it was confirmed that the pilot, as the target at a first specific position P1a, can be dazzled by the specularly reflected light RL1 of sunlight SL0 generated in group A 3ga.

[0132] On the other hand, for group B 3gb, following the flow shown in Figure 12, a graph was created in which points were plotted showing the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion. As a result, a graph was obtained in which points were plotted in the region Ae4 enclosed by a thick dashed line, as shown in Figure 22. More specifically, a graph was obtained in which points were plotted below the straight line Lth. From this graph, it was confirmed that for group B 3gb, even when the first solar cell module 31 was applied to each of the second number of solar cell modules 3 constituting group B 3gb, there was no time when the retinal irradiance Er, as the estimated irradiance E1, was greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion.

[0133] Therefore, based on the configuration shown in Figure 20, group A 3ga was changed from group 1 3g1 to group 2 3g2, as shown in Figure 23. More specifically, each of the first number of solar cell modules 3 constituting group A 3ga was designated as a second solar cell module 32. In Figure 23, group 2 3g2 is hatched with a diagonal line rising to the left. The direction in which the second light-receiving surface 30s2 of the second solar cell module 32 faces was set to the same direction as the first light-receiving surface 30s1 of the first solar cell module 31, with an installation angle of 20 degrees and an installation orientation of 180 degrees. The dispersion angle β at the second light-receiving surface 30s2 was set to 57.3 degrees, calculated from the measured results. The specular reflectance ρ(θ) at the second light-receiving surface 30s2 was the value measured using a measuring device. For example, for the second light-receiving surface 30s2, the specular reflectance ρ(85 degrees) was 5% when the incident angle θ of sunlight SL0 was 85 degrees. Furthermore, the condition was that a specific position P1 was a specific position (first specific position) P1a in the cockpit 5c of an aircraft 5 in landing approach.

[0134] Then, for group A3ga, which was changed from group 13g1 to group 23g2, a graph was created plotting points showing the relationship between the visual angle ω related to the first reflection region Ar1 and the retinal irradiance Er corresponding to the estimated irradiance E1 when the sun 900 performs its year-round diurnal motion, following the flow shown in Figure 12. As a result, a graph was obtained in which points are plotted in the region Ae5 enclosed by a thick dashed line, as shown in Figure 24. More specifically, a graph was obtained in which points are plotted below the straight line Lth. From this graph, it was confirmed that for group A3ga, when the second solar cell module 32 is applied to each of the first number of solar cell modules 3 constituting group A3ga, there is no longer a time when the retinal irradiance Er, as the estimated irradiance E1, is greater than the critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its year-round diurnal motion. In other words, it was confirmed that if group A 3ga is group 2 3g2, the occurrence of a situation in which the pilot, as the target person at the first specific position P1a, may be dazzled by the specularly reflected light RL1 of sunlight SL0 generated in group A 3ga can be reduced.

[0135] <1-7. Other Components> For example, as shown in Figure 25, consider a case where the first group 3g1 includes a row of solar cell modules 3 with a first number of rows (also called the first module row) 3La, and the second group 3g2 includes a row of solar cell modules 3 with a second number of rows (also called the second module row) 3Lb. Each first module row 3La consists of two or more solar cell modules 3. Each second module row 3Lb consists of two or more solar cell modules 3.

[0136] In the example shown in Figure 25, the first number of columns is 3, and the second number of columns is 3. In each first module column 3La, two or more solar cell modules 3 are arranged in the first horizontal direction Dr1. In each second module column 3Lb, two or more solar cell modules 3 are arranged in the first horizontal direction Dr1. In the first group 3g1, the first module column 3La with the first number of columns is arranged in the second horizontal direction Dr2. In the second group 3g2, the second module column 3Lb with the second number of columns is arranged in the second horizontal direction Dr2.

[0137] Here, when viewed from above, the spacing between columns in the first module column 3La of the first number of columns (also called the first column spacing) may be less than or equal to a predetermined first spacing d1, and the spacing between columns in the second module column 3Lb of the second number of columns (also called the second column spacing) may be less than or equal to a predetermined first spacing d1. The first column spacing may be the distance between two adjacent first module columns 3La when viewed from above. The second column spacing may be the distance between two adjacent second module columns 3Lb when viewed from above. The predetermined first spacing d1 may be a distance having a predetermined first length. In other words, when viewed from above, the distance between two adjacent first module columns 3La and the distance between two adjacent second module columns 3Lb may each be less than or equal to a predetermined first length.

[0138] In the example shown in Figure 25, the first column spacing and the second column spacing are each a constant value of the first spacing d1. From another perspective, in a plan view, the distance between two adjacent first module columns 3La and the distance between two adjacent second module columns 3Lb are each distances having a constant value of the first length.

[0139] Here, when viewed from above, the distance between the first group 3g1 and the second group 3g2 may be greater than or equal to the second interval d2, which is greater than the first interval d1. The distance between the first group 3g1 and the second group 3g2 may be the distance between the first group 3g1 and the second group 3g2 when viewed from above. The second interval d2 may be a distance having a predetermined second length. In other words, when viewed from above, the distance between the first group 3g1 and the second group 3g2 may be greater than or equal to the second length, which is greater than the first length.

[0140] In the example shown in Figure 25, the distance between the first group 3g1 and the second group 3g2 is a second distance d2, which is a constant value. From another perspective, when viewed from above, the distance between the first group 3g1 and the second group 3g2 is a distance with a second length, which is a constant value.

[0141] If the above configuration is adopted, the amount of electricity generated per unit area of ​​land in the solar power generation system 100 can be increased by arranging the rows of solar cell modules 3 in each module group 3g of the first group 3g1 and the second group 3g2 with a first interval d1 or less. In addition, by making the interval between the first group 3g1 and the second group 3g2 larger than the first interval d1, the first group 3g1 and the second group 3g2 can be clearly defined. This can reduce the management burden when constructing the first group 3g1 and the second group 3g2.

[0142] By the way, in the example shown in Figure 25, the first column spacing and the second column spacing were both set to a constant value of the first spacing d1, but this is not the only example. Here, the first column spacing and the second column spacing do not have to be set to a constant value of the first spacing d1, as long as they are less than or equal to the first spacing d1. From another perspective, the distance between two adjacent first module columns 3La and the distance between two adjacent second module columns 3Lb do not have to be set to a constant value of the first length, as long as they are less than or equal to the first length.

[0143] Here, for example, as shown in Figure 19, if the first group 3g1 has multiple module unit rows 3ar, then in a plan view, the spacing between adjacent module unit rows 3ar may be a constant first spacing d1. From another perspective, in a plan view, the distance between two adjacent module unit rows 3ar in the first group 3g1 may be a distance that has a constant first length. Here, in a plan view, the spacing between adjacent module unit rows 3ar in the first group 3g1 does not have to be a constant first spacing d1, as long as it is less than or equal to the first spacing d1. From another perspective, in a plan view, the distance between two adjacent module unit rows 3ar in the first group 3g1 does not have to be a constant first length, as long as it is less than or equal to the first length.

[0144] Furthermore, for example, as shown in Figure 19, if the second group 3g2 has multiple module unit rows 3ar, then in a plan view, the spacing between adjacent module unit rows 3ar may be a constant first spacing d1. From another perspective, in a plan view, the distance between two adjacent module unit rows 3ar in the second group 3g2 may be a distance that has a constant first length. Here, in a plan view, the spacing between adjacent module unit rows 3ar in the second group 3g2 does not have to be a constant first spacing d1, as long as it is less than or equal to the first spacing d1. From another perspective, in a plan view, the distance between two adjacent module unit rows 3ar in the second group 3g2 does not have to be a constant first length, as long as it is less than or equal to the first length.

[0145] Furthermore, in the example shown in Figure 25, the interval between the first group 3g1 and the second group 3g2 was the second interval d2 as a constant value, but this is not the only example. Here, the interval between the first group 3g1 and the second group 3g2 does not have to be the second interval d2, as long as it is greater than or equal to the second interval d2. From another perspective, the distance between the first group 3g1 and the second group 3g2 does not have to be the second length, as long as it is greater than or equal to the second length.

[0146] <1-8. Summary of the First Embodiment> In the photovoltaic power generation system 100 according to the first embodiment, for example, a plurality of solar cell modules 3 installed on land along the longitudinal direction of runway 1 or landing strip 2 at an airport 200 have a plurality of module groups 3g, including a first group 3g1 and a second group 3g2. The first group 3g1 consists of a plurality of first solar cell modules 31. The second group 3g2 consists of two or more solar cell modules 3, including one or more second solar cell modules 32. The reflectance of light at the second light-receiving surface 30s2 of the second solar cell module 32 is smaller than the reflectance of light at the first light-receiving surface 30s1 of the first solar cell module 31. When the sun 900 performs its diurnal motion throughout the year, the estimated irradiance E1 of the reflected light incident on a specific position P1 in one or more spaces, such as the cockpit 5c of an aircraft 5 in flight and the control room 6c of the control tower 6, in accordance with the reflection of sunlight SL0 by the plurality of solar cell modules 3, is less than or equal to a predetermined irradiance.

[0147] Here, assuming the installation of multiple solar cell modules 3 of a single type, there may be specific plots of land where the orientation of the light-receiving surface 30s for obtaining high power generation coincides with the orientation of the light-receiving surface 30s at a specific location P1 in which a person would feel dazzled by the reflected sunlight SL0 from the light-receiving surface 30s. In contrast, the solar power generation system 100 according to the first embodiment employs a configuration in which two or more types of solar cell modules 3 with different light reflectivity at the light-receiving surface 30s are arranged. As a result, even if the orientation of the light-receiving surface 30s of each solar cell module 3 is set to the orientation for obtaining high power generation, by placing a second solar cell module 32 on a specific plot of land, the degree to which a person would feel dazzled by the reflected sunlight SL0 from the light-receiving surface 30s at a specific location P1 can be reduced to an acceptable range. Furthermore, with the above configuration, for example, compared to a configuration in which the orientation of the light-receiving surface 30s of the first solar cell module 31 is east-facing or west-facing on a specific plot of land, it is possible to increase the power generation amount of the solar power generation system 100. Furthermore, with the above configuration, it is possible to increase the amount of power generated in the photovoltaic power generation system 100 compared to the case where all of the multiple solar cell modules 3 are installed as multiple second solar cell modules 32, with the light-receiving surface 30s of each second solar cell module 32 facing the midline.

[0148] Therefore, according to the photovoltaic power generation system 100 of the first embodiment, glare caused by the reflection of sunlight SL0 can be reduced. From another perspective, the photovoltaic power generation system 100 can reduce glare caused by the reflection of sunlight SL0 while reducing the decrease in power generation.

[0149] <2. Other Embodiments> This disclosure is not limited to the first embodiment described above, and various modifications and improvements are possible without departing from the gist of this disclosure.

[0150] <2-1. Second Embodiment> In the first embodiment described above, for example, the area of ​​land on which multiple solar cell modules 3 are installed can be increased by arranging multiple solar cell modules 3 on the land on both sides of the runway 1 or landing strip 2. This can improve the amount of power generated in the photovoltaic power generation system 100. In addition, the glare caused by the reflection of sunlight SL0 can be reduced by reducing the reflectivity of the light-receiving surface 30s of the solar cell module 3 installed in a position where specular reflected light RL1 is directed toward the pilot of the aircraft 5 in landing approach.

[0151] In the second embodiment, when the sun 900 performs its diurnal motion throughout the year, there may be no time when the landing flight path of the aircraft 5 and the optical path of the specularly reflected light RL1 generated on the multiple light-receiving surfaces 30s of the first group 3g1 in response to the irradiation of sunlight SL0 overlap, but there may be time when the landing flight path of the aircraft 5 and the optical path of the specularly reflected light RL1 generated on the multiple light-receiving surfaces 30s of the second group 3g2 in response to the irradiation of sunlight SL0 overlap. The landing flight path of the aircraft 5 may be the path taken by the aircraft 5 in landing approach toward runway 1, as described above. More specifically, the landing flight path may be the path taken by the aircraft 5 toward the landing reference point Pc0, which is the centroid of the target point marker 1a on runway 1.

[0152] Here, for example, consider the case shown in Figure 26, where the land along the longitudinal direction of runway 1 or landing strip 2 at airport 200 includes a first area A1 and a second area A2. The first area A1 and the second area A2 are located on either side of runway 1 or landing strip 2 in the width direction of runway 1, perpendicular to the longitudinal direction of runway 1 or landing strip 2. The second group 3g2 may be installed in the first area A1, and the first group 3g1 may be installed in the second area A2. In the example shown in Figure 26, the longitudinal direction of runway 1 is along the +X direction, and the width direction of runway 1 is along the +Y direction. The first area A1 is located on the +Y side of runway 1. The second area A2 is located on the -Y side of runway 1. In Figure 26, an example of the solar light path SL0 is shown by a thin dashed-dotted arrow, and an example of the specular reflection light path RL1 is shown by a thin double-dashed-dotted arrow.

[0153] Here, for example, as described above, the specular reflected light RL1 generated at the light-receiving surface 30s in response to irradiation with sunlight SL0 includes a first reflected light and a second reflected light. The first reflected light is the reflected light with the peak intensity among the reflected light of sunlight SL0 generated at the light-receiving surface 30s. The second reflected light is the reflected light generated at the light-receiving surface 30s due to a slight dispersion in the specular reflection direction. The second reflected light has an intensity of a predetermined intensity Th1 or greater, which is closer to the peak intensity of the first reflected light than the intensity of the diffuse reflected light generated by diffuse reflection at the light-receiving surface 30s.

[0154] Furthermore, as shown in Figure 27, when the sun 900 performs its annual diurnal motion, there does not need to be a time when the region (also called the first passing region) Ap1 through which a portion of the reflected light of sunlight SL0 generated at each of the light-receiving surfaces 30s of the multiple first solar cell modules 31 in the first group 3g1 passes and the landing flight path Fr1 of the aircraft 5 overlap. The first specific reflected light includes the first reflected light (also called the first A reflected light) and the second reflected light (also called the second A reflected light) which has an intensity of a predetermined intensity (also called the first predetermined intensity) that is closer to the peak intensity (also called the first peak intensity) of the first A reflected light than the intensity of the diffuse reflected light (also called the first diffuse reflected light). Here, the first A reflected light may be the reflected light having the first peak intensity among the reflected light of sunlight SL0 generated at each of the light-receiving surfaces 30s of the multiple first solar cell modules 31 in the first group 3g1. The first diffuse reflected light may be the diffuse reflected light of sunlight SL0 generated at each of the light-receiving surfaces 30s of the multiple first solar cell modules 31 in the first group 3g1. The second A reflected light may be the reflected light of sunlight SL0 generated at each of the light-receiving surfaces 30s of the multiple first solar cell modules 31 in the first group 3g1, having an intensity of a first predetermined intensity or greater, which is closer to the first peak intensity of the first A reflected light than the intensity of the first diffuse reflected light. The first predetermined intensity may be, for example, an intensity of a predetermined ratio (also called the first predetermined ratio) of the first peak intensity. The first predetermined ratio may be, for example, 90 percent (%), 50%, 25%, or any ratio in the range of 25% to 95%.

[0155] Furthermore, as shown in Figure 27, for example, when the sun 900 performs its annual diurnal motion, there may be a time when a region (also called the second passing region) Ap2 through which a portion of the reflected light (also called the second specific reflected light) of the reflected light of sunlight SL0 generated at the light-receiving surfaces 30s of two or more solar cell modules 3 in the second group 3g2 passes coincides with the landing flight path Fr1 of the aircraft 5. The second specific reflected light includes the first reflected light (also called the first B reflected light) and the second reflected light (also called the second B reflected light) which has an intensity of a predetermined intensity (also called the second predetermined intensity) that is closer to the peak intensity (also called the second peak intensity) of the first B reflected light (also called the second diffuse reflected light) than the intensity of the diffuse reflected light (also called the second diffuse reflected light). Here, the first B reflected light may be the reflected light having the second peak intensity among the reflected light of sunlight SL0 generated at the light-receiving surfaces 30s of two or more solar cell modules 3 in the second group 3g2. The second diffuse reflected light may be the diffuse reflected light of sunlight SL0 generated at the light-receiving surface 30s of each of the two or more solar cell modules 3 in the second group 3g2. The second B reflected light may be the reflected light of sunlight SL0 generated at the light-receiving surface 30s of each of the two or more solar cell modules 3 in the second group 3g2, having an intensity of a second predetermined intensity or greater, which is closer to the second peak intensity of the first B reflected light than the intensity of the second diffuse reflected light. The second predetermined intensity may be, for example, an intensity of a predetermined ratio (also called the second predetermined ratio) of the second peak intensity. The second predetermined ratio may be, for example, 90 percent (%), 50%, 25%, or any ratio in the range of 25% to 95%. The second predetermined ratio may be the same as the first predetermined ratio.

[0156] In Figure 27, the multiple light-receiving surfaces 30s in the first group 3g1 are conveniently shown as a single light-receiving surface 30s, and the multiple light-receiving surfaces 30s in the second group 3g2 are conveniently shown as a single light-receiving surface 30s. In Figure 27, the outer edge of the optical path of sunlight SL0 toward the multiple light-receiving surfaces 30s is indicated by a thin dashed-dotted arrow. In Figure 27, the outer edge of the first passing region Ap1 is indicated by a thin double-dotted arrow, and the outer edge of the second passing region Ap2 is indicated by a thin double-dotted arrow. The first passing region Ap1 includes the region through which the first A reflected light passes (also called the first A passing region) Ap11, and the region through which the second A reflected light passes (also called the first B passing region) Ap12. The second pass region Ap2 includes the region through which the first B reflected light passes (also called the second A pass region) Ap21 and the region through which the second B reflected light passes (also called the second B pass region) Ap22. In Figure 27, the first A pass region Ap11 and the second A pass region Ap21 are each hatched with a diagonal line rising to the left, and the first B pass region Ap12 and the second B pass region Ap22 are each hatched with a sandy pattern. In Figure 27, the boundary between the first A pass region Ap11 and the first B pass region Ap12, and the boundary between the second A pass region Ap21 and the second B pass region Ap22, are each indicated by arrows drawn with thin dashed lines. In Figure 27, the landing flight path Fr1 is conveniently shown as a straight dashed line.

[0157] From another perspective, in the first passing region Ap1, the first A passing region Ap11 may be the region through which specularly reflected light of sunlight SL0, which is directed toward the first reflection direction that produces ideal specular reflection on the multiple light-receiving surfaces 30s in the first group 3g1, passes. In the first passing region Ap1, the first B passing region Ap12 may be the region through which specularly reflected light, which spreads according to the dispersion angle β of the specular reflection direction on the multiple light-receiving surfaces 30s in the first group 3g1, passes. In the second passing region Ap2, the second A passing region Ap21 may be the region through which specularly reflected light of sunlight SL0, which is directed toward the first reflection direction that produces ideal specular reflection on the multiple light-receiving surfaces 30s in the second group 3g2, passes. In the second passing region Ap2, the second B passing region Ap22 may be the region through which specularly reflected light, which spreads according to the dispersion angle β of the specular reflection direction on the multiple light-receiving surfaces 30s in the second group 3g2, passes.

[0158] In addition, in the example shown in Figures 26 and 27, the positions of the first area A1 and the second area A2 at airport 200 may be swapped, as shown in Figures 28 and 29.

[0159] <2-2. Third Embodiment> In the first embodiment described above, for example, as shown in Figure 30, the first virtual line Lv1 is defined as the virtual line connecting a first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach to the landing reference point Pc0 of the runway 1. The second virtual line Lv2 is defined as the virtual line connecting the first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach to the reference point (also called the first reference point) Pc1 of the first group 3g1. The third virtual line Lv3 is defined as the virtual line connecting the first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach to the reference point (also called the second reference point) Pc2 of the second group 3g2. The first angle θ1 is defined as the angle formed by the first virtual line Lv1 and the second virtual line Lv2. The second angle θ2 is defined as the angle formed by the first virtual line Lv1 and the third virtual line Lv3. As described above, the landing reference point Pc0 may be the centroid of the target point marker 1a on runway 1. The first reference point Pc1 may be, for example, the centroid of the first group 3g1 when viewed from above. The second reference point Pc2 may be, for example, the centroid of the second group 3g2 when viewed from above.

[0160] Here, for example, the first angle θ1 may be greater than the second angle θ2. If this configuration is adopted, the second solar cell module 32, which has a second light-receiving surface 30s2 with a reflectivity relatively smaller than that of the first light-receiving surface 30s1, can be installed on the ground closer to the central field of vision of the pilot of the aircraft 5 in landing approach, thereby reducing the degree to which the pilot feels glare due to the reflection of sunlight SL0.

[0161] From another perspective, for example, the distance Ds1 from the landing reference point Pc0, which is the centroid of the target point marker 1a on runway 1, to the first group 3g1 (also called the first distance) may be greater than the distance Ds2 from the landing reference point Pc0, which is the centroid of the target point marker 1a on runway 1, to the second group 3g2 (also called the second distance). If this configuration is adopted, the glare experienced by the pilot due to the reflection of sunlight SL0 can be reduced by installing the second solar cell module 32, which has a second light-receiving surface 30s2 with a relatively lower reflectivity than the first light-receiving surface 30s1, on the ground closer to the central field of view of the pilot of the aircraft 5 in landing approach.

[0162] In the example shown in Figure 30, of the first and second regions A1 and A2 located on either side of the runway 1 in the direction of the +Y direction, which is the width direction of the runway 1, both module groups 3g1 and 3g2 are installed in the first region A1, but this is not limited to this. For example, both module groups 3g1 and 3g2 may be installed in the second region A2, or the first region 3g1 may be installed in the first region A1 and the second region 3g2 may be installed in the second region A2, or the second region 3g2 may be installed in the first region A1 and the first region 3g1 may be installed in the second region A2.

[0163] <2-3. Fourth Embodiment> In the first embodiment described above, for example, as shown in Figure 31, the distance from the centroid of the first target marker 1a1 (also called the first landing reference point) Pc0a to the reference point (first reference point) Pc1 of the first group 3g1 is defined as the third distance Ds3. The distance from the centroid of the second target marker 1a2 (also called the second landing reference point) Pc0b to the first reference point Pc1 of the first group 3g1 is defined as the fourth distance Ds4. The distance from the centroid of the first target marker 1a1, the first landing reference point Pc0a, to the reference point (second reference point) Pc2 of the second group 3g2 is defined as the fifth distance Ds5. The distance from the centroid of the second target marker 1a2, the second landing reference point Pc0b, to the second reference point Pc2 of the second group 3g2 is defined as the sixth distance Ds6. The first reference point Pc1 may be, for example, the centroid of the first group 3g1 when viewed from above. The second reference point Pc2 may be, for example, the centroid of the second group 3g2 when viewed from above.

[0164] Here, for example, either the fifth distance Ds5 or the sixth distance Ds6 may be smaller than either the third distance Ds3 or the fourth distance Ds4. This allows the second solar cell module 32, which has a second light-receiving surface 30s2 with a reflectivity relatively smaller than that of the first light-receiving surface 30s1, to be installed on land closer to the target point marker 1a of the runway 1. As a result, by installing the second solar cell module 32, which has a second light-receiving surface 30s2 with a reflectivity relatively smaller than that of the first light-receiving surface 30s1, on land closer to the central field of view of the pilot of the aircraft 5 in landing approach, glare to the pilot due to the reflection of sunlight SL0 can be reduced.

[0165] In one example shown in Figure 31, of the first and second regions A1 and A2 located on either side of the runway 1 in the +Y direction, which is the width direction of the runway 1, both module groups 3g1 and 3g2 are installed in the first region A1. The first group 3g1 and the second group 3g2 are aligned in the direction along the longitudinal direction of the runway 1. Here, for example, both module groups 3g1 and 3g2 may be installed in the second region A2. In this case, the first group 3g1 and the second group 3g2 may be aligned in the direction along the longitudinal direction of the runway 1. Also, for example, the first group 3g1 may be installed in the first region A1 and the second group 3g2 may be installed in the second region A2, or the second group 3g2 may be installed in the first region A1 and the first group 3g1 may be installed in the second region A2.

[0166] <2-4. Fifth Embodiment> In the fourth embodiment described above, for example, as shown in Figure 32, we assume that a plurality of module groups 3g include two second groups 3g2 located on either side of the first group 3g1 in the longitudinal direction of the runway 1. The two second groups 3g2 are designated as second A group 3g2a and second B group 3g2b. Each of second A group 3g2a and second B group 3g2b consists of two or more solar cell modules 3, each containing one or more second solar cell modules 32. Furthermore, the distance from the first landing reference point Pc0a, which is the centroid of the first target point marker 1a1, to the reference point (also called the second A reference point) Pc2a of second A group 3g2a is defined as the fifth A distance Ds5a. The distance from the second landing reference point Pc0b, which is the centroid of the second target point marker 1a2, to the second A reference point Pc2a of second A group 3g2a is defined as the sixth A distance Ds6a. The distance from the first landing reference point Pc0a, which is the centroid of the first target point marker 1a1, to the reference point (also called the second B reference point) Pc2b of the second B group 3g2b is defined as the 5B distance Ds5b. The distance from the second landing reference point Pc0b, which is the centroid of the second target point marker 1a2, to the second B reference point Pc2b of the second B group 3g2b is defined as the 6B distance Ds6b. The second A reference point Pc2a may, for example, be the centroid of the second A group 3g2a when viewed from above. The second B reference point Pc2b may, for example, be the centroid of the second B group 3g2b when viewed from above.

[0167] Here, for example, the distance of either the 5A distance Ds5a or the 6A distance Ds6a may be smaller than the distance of either the 3rd distance Ds3 or the 4th distance Ds4. Furthermore, the distance of either the 5B distance Ds5b or the 6B distance Ds6b may be smaller than the distance of either the 3rd distance Ds3 or the 4th distance Ds4. This allows the second solar cell module 32, which has a second light-receiving surface 30s2 with a reflectivity relatively smaller than that of the first light-receiving surface 30s1, to be installed on land closer to the target point marker 1a of the runway 1. As a result, by installing the second solar cell module 32, which has a second light-receiving surface 30s2 with a reflectivity relatively smaller than that of the first light-receiving surface 30s1, on land closer to the central field of view of the pilot of the aircraft 5 in landing approach, glare to the pilot due to the reflection of sunlight SL0 can be reduced.

[0168] In one example shown in Figure 32, of the first and second regions A1 and A2 located on either side of the runway 1 in the +Y direction, which is the width direction of the runway 1, all module groups 3g of the first group 3g1 and the two second groups 3g2 are installed in the first region A1, but this is not limited to this. For example, all module groups 3g of the first group 3g1 and the two second groups 3g2 may be installed in the second region A2.

[0169] <2-5. Sixth Embodiment> In each of the first to fifth embodiments described above, for example, as shown in Figure 33, the group of modules 3g may include a third module group (also called the third group) 3g3 composed of a third number of solar cell modules 3. The third number may be any number of two or more.

[0170] Here, for example, consider the case shown in Figure 33, where the land along the longitudinal direction of runway 1 or landing strip 2 at airport 200 includes a first area A1 and a second area A2. The first area A1 and the second area A2 are located on either side of runway 1 or landing strip 2 in the width direction of runway 1, perpendicular to the longitudinal direction of runway 1 or landing strip 2. The first group 3g1 and the third group 3g3 are each located in the first area A1, and the third group 3g3 may be located closer to runway 1 than the first group 3g1. In the example shown in Figure 33, the longitudinal direction of runway 1 is along the +X direction, and the width direction of runway 1 is along the +Y direction. The first area A1 is located on the +Y side of runway 1. The second area A2 is located on the -Y side of runway 1.

[0171] Here, for example, as shown in Figures 33 and 34, for the first group 3g1, the first vector V1 is a vector that virtually extends in a direction away from the first light-receiving surface (first light-receiving surface) 30s1 along the normal direction of each light-receiving surface (first light-receiving surface) 30s1 of the multiple first solar cell modules 31. The first vector V1 may be, for example, a vector starting from the reference point (first reference point) Pc1 of the first group 3g1. The first reference point Pc1 may be, for example, the centroid of the first group 3g1 when viewed from above. Furthermore, the component of the first vector V1 in the short-side direction (width direction) of the runway 1 is defined as the first horizontal vector V1h.

[0172] Furthermore, for example, as shown in Figures 33 and 34, for the third group 3g3, the second vector V3 is a vector that virtually extends in the direction away from the third light-receiving surface 30s3 (also called the third light-receiving surface 30s3) along the normal direction of each light-receiving surface 30s of the third number of solar cell modules 3. The second vector V3 may be, for example, a vector starting from the reference point (also called the third reference point) Pc3 of the third group 3g3. The third reference point Pc3 may be, for example, the centroid of the third group 3g3 when viewed from above. Also, the component of the second vector V3 in the short-side direction (width direction) of the runway 1 is defined as the second horizontal vector V3h.

[0173] Here, for example, the direction of the first horizontal vector V1h and the direction of the second horizontal vector V3h may be opposite, and the second horizontal vector V3h may extend in a direction away from runway 1. In other words, for example, the third light-receiving surface 30s3 of the third group 3g3 may be inclined in a manner that faces away from runway 1.

[0174] If this configuration is adopted, the angle between the vector V35 extending from the third light-receiving surface 30s3 of the third group 3g3 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach and the second vector V3 (also called the third angle) may be larger than the angle between the vector V15 extending from the first light-receiving surface 30s1 of the first group 3g1 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach and the first vector V1 (also called the fourth angle). The starting point of the second vector V3 and the starting point of vector V35 may be the same, and the starting point of the first vector V1 and the starting point of vector V15 may be the same. In this case, when viewed from the cockpit 5c of the aircraft 5 in landing approach, the third light-receiving surface 30s3 of the third group 3g3, which is located closer to the runway 1 than the first group 3g1, may appear smaller than the first light-receiving surface 30s1 of the first group 3g1. This can reduce the amount of reflected light from the third group 3g3, which is generated in response to the irradiation of sunlight SL0, and directed towards the cockpit 5c of the aircraft 5 in landing approach. As a result, the degree to which the pilot of the aircraft 5 in landing approach perceives the reflected light from sunlight SL0 in the photovoltaic power generation system 100 as dazzling can be reduced.

[0175] Here, for example, if the aircraft 5 in landing approach is far from the runway 1, the third angle may be less than 90 degrees and may approach 90 degrees. In this case, if specular reflected light RL1 is generated on the third light-receiving surface 30s3 toward the cockpit 5c in response to the irradiation of sunlight SL0, the angle of incidence of sunlight SL0 on the third light-receiving surface 30s3 may be large. However, if the cockpit 5c is far from the third group 3g3, the multiple light-receiving surfaces 30s of the third group 3g3 will appear small when viewed from the cockpit 5c. As a result, the viewing angle of the region (first reflection region Ar1) on the multiple light-receiving surfaces 30s of the third group 3g3 toward the cockpit 5c may be small when viewed from the cockpit 5c. Therefore, the degree to which the pilot of the aircraft 5 in landing approach perceives glare from the reflected light generated on the third group 3g3 in response to the irradiation of sunlight SL0 may be reduced. Furthermore, for example, when an aircraft 5 in landing approach approaches runway 1 and the third angle becomes 90 degrees or more, the specular reflected light RL1 directed toward the cockpit 5c, generated by the third group 3g3 in response to the irradiation of sunlight SL0, may be almost completely eliminated. As a result, the degree to which the pilot of the aircraft 5 in landing approach perceives the reflected light of sunlight SL0 from the photovoltaic power generation system 100 as dazzling may be reduced.

[0176] Here, let's assume that the third group 3g3, which is closer to runway 1 than the first group 3g1, is replaced with the first group 3g1. In this case, whether the aircraft 5 in landing approach is far from runway 1 or approaching runway 1, the multiple light-receiving surfaces 30s of the first group 3g1, which replaced the third group 3g3, may appear larger when viewed from the cockpit 5c. As a result, the viewing angle of the region (first reflection region Ar1) that generates specular reflected light RL1 toward the cockpit 5c in the first group 3g1, which replaced the third group 3g3, may increase when viewed from the cockpit 5c. Consequently, the degree to which the pilot of the aircraft 5 in landing approach perceives the reflected light of sunlight SL0 from the photovoltaic power generation system 100 as dazzling may increase.

[0177] In contrast, in the sixth embodiment, by installing the third group 3g3 near the runway 1, the degree to which the reflected light of sunlight SL0 from the solar power generation system 100 is perceived as dazzling by the pilot of the aircraft 5 in landing approach can be reduced.

[0178] <2-6. Seventh Embodiment> In each of the first to fifth embodiments described above, for example, as shown in Figure 35, the group of modules 3g may include a fourth module group (also called the fourth group) 3g4 composed of a fourth number of solar cell modules 3. The fourth number may be any number of two or more.

[0179] Here, for example, consider the case shown in Figure 35, where the land along the longitudinal direction of runway 1 or landing strip 2 at airport 200 includes a first area A1 and a second area A2. The first area A1 and the second area A2 are located on either side of runway 1 or landing strip 2 in the width direction of runway 1, perpendicular to the longitudinal direction of runway 1 or landing strip 2. The first group 3g1 may be installed in the second area A2, and the fourth group 3g4 may be installed in the first area A1. In the example shown in Figure 35, the longitudinal direction of runway 1 is along the +X direction, and the width direction of runway 1 is along the +Y direction. The first area A1 is located on the +Y side of runway 1. The second area A2 is located on the -Y side of runway 1.

[0180] Here, for example, as shown in Figures 35 and 36, for the first group 3g1, the first vector V1 is a vector that virtually extends in a direction away from the first light-receiving surface (first light-receiving surface) 30s1 along the normal direction of each light-receiving surface (first light-receiving surface) 30s1 of the multiple first solar cell modules 31. The first vector V1 may be, for example, a vector starting from the reference point (first reference point) Pc1 of the first group 3g1. The first reference point Pc1 may be, for example, the centroid of the first group 3g1 when viewed from above. Furthermore, the component of the first vector V1 in the short-side direction (width direction) of the runway 1 is defined as the first horizontal vector V1h.

[0181] Furthermore, for example, as shown in Figures 35 and 36, for the fourth group 3g4, the third vector V4 is a vector that virtually extends away from the fourth light-receiving surface 30s4 (also called the fourth light-receiving surface 30s4) along the normal direction of each of the fourth number of solar cell modules 3. The third vector V4 may be, for example, a vector starting from the reference point (also called the fourth reference point) Pc4 of the fourth group 3g4. The fourth reference point Pc4 may be, for example, the centroid of the fourth group 3g4 when viewed from above. Also, the component of the third vector V4 in the short-side direction (width direction) of the runway 1 is defined as the third horizontal vector V4h.

[0182] Here, for example, the direction of the first horizontal vector V1h and the direction of the third horizontal vector V4h may be opposite, and both the direction of the first horizontal vector V1h and the third horizontal vector V4h may be away from the runway 1. In other words, for example, both the first light-receiving surface 30s1 of the first group 3g1 and the fourth light-receiving surface 30s4 of the fourth group 3g4 may be inclined in a manner that faces away from the runway 1.

[0183] If this configuration is adopted, the angle between the first light-receiving surface 30s1 of the first group 3g1 and the first vector V1 (also called the fifth angle), and the angle between the vector V45 and the third vector V4 (also called the sixth angle), which extends from the fourth light-receiving surface 30s4 of the fourth group 3g4 to the first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach, can both be made larger. The starting point of the first vector V1 and the starting point of vector V15 may be the same, and the starting point of the third vector V4 and the starting point of vector V45 may be the same. In this configuration, when viewed from the cockpit 5c of the aircraft 5 in landing approach, the area of ​​the first light-receiving surface 30s1 in the first group 3g1 and the area of ​​the fourth light-receiving surface 30s4 in the fourth group 3g4 can both appear smaller. This reduces both the amount of reflected light directed towards the cockpit 5c of the aircraft 5 in landing approach, generated by the first group 3g1 in response to the irradiation of sunlight SL0, and the amount of reflected light directed towards the cockpit 5c of the aircraft 5 in landing approach, generated by the fourth group 3g4 in response to the irradiation of sunlight SL0. As a result, the degree to which the reflected light of sunlight SL0 from the photovoltaic power generation system 100 is perceived as dazzling by the pilot of the aircraft 5 in landing approach can be reduced.

[0184] <2-7. Eighth Embodiment> In each of the first to fifth embodiments described above, for example, as shown in Figure 37, the plurality of module groups 3g may include a fifth module group (also called the fifth group) 3g5 composed of a fifth number of solar cell modules 3, and a sixth module group (also called the sixth group) 3g6 composed of a sixth number of solar cell modules 3. The fifth number and the sixth number may both be any number of two or more.

[0185] Here, for example, consider the case shown in Figure 37, where the land along the longitudinal direction of runway 1 or landing strip 2 at airport 200 includes a first area A1 and a second area A2. The first area A1 and the second area A2 are located on either side of runway 1 or landing strip 2 in the width direction of runway 1, perpendicular to the longitudinal direction of runway 1 or landing strip 2. The fifth group 3g5 may be installed in the first area A1, and the sixth group 3g6 may be installed in the second area A2. In the example shown in Figure 37, the longitudinal direction of runway 1 is along the +X direction, and the width direction of runway 1 is along the +Y direction. The first area A1 is located on the +Y side of runway 1. The second area A2 is located on the -Y side of runway 1.

[0186] Here, for example, as shown in Figures 37 and 38, for the fifth group 3g5, the fourth vector V5 is defined as a vector that virtually extends away from the fifth light-receiving surface 30s5 along the normal direction of the light-receiving surface 30s5 (also called the fifth light-receiving surface 30s5) of each of the fifth number of solar cell modules 3. The fourth vector V5 may be, for example, a vector starting from the reference point (also called the fifth reference point) Pc5 of the fifth group 3g5. The fifth reference point Pc5 may be, for example, the centroid of the fifth group 3g5 when viewed from above. Furthermore, the component of the fourth vector V5 in the short-side direction (width direction) of the runway 1 is defined as the fourth horizontal vector V5h.

[0187] Furthermore, for example, as shown in Figures 37 and 38, for the sixth group 3g6, the fifth vector V6 is defined as a vector that virtually extends away from the sixth light-receiving surface 30s6 (also called the sixth light-receiving surface 30s6) along the normal direction of each light-receiving surface 30s of the sixth number of solar cell modules 3. The fifth vector V6 may, for example, be a vector starting from the reference point (also called the sixth reference point) Pc6 of the sixth group 3g6. The sixth reference point Pc6 may, for example, be the centroid of the sixth group 3g6 when viewed from above. Also, the component of the fifth vector V6 in the short-side direction (width direction) of the runway 1 is defined as the fifth horizontal vector V6h.

[0188] Here, for example, the direction of the fourth horizontal vector V5h and the direction of the fifth horizontal vector V6h may be opposite, and both the direction of the fourth horizontal vector V5h and the fifth horizontal vector V6h may be away from the runway 1. In other words, for example, both the fifth light-receiving surface 30s5 of the fifth group 3g5 and the sixth light-receiving surface 30s6 of the sixth group 3g6 may be inclined to face away from the runway 1.

[0189] If this configuration is adopted, the angle between the vector V55 extending from the fifth light-receiving surface 30s5 of the fifth group 3g5 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach and the fourth vector V5 (also called the seventh angle) may become larger. Also, the angle between the vector V65 extending from the sixth light-receiving surface 30s6 of the sixth group 3g6 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing approach and the fifth vector V6 (also called the eighth angle) may become larger. The starting point of the fourth vector V5 and the starting point of vector V55 may be the same, and the starting point of the fifth vector V6 and the starting point of vector V65 may be the same. In this case, when viewed from the cockpit 5c of the aircraft 5 in landing approach, both the fifth light-receiving surface 30s5 of the fifth group 3g5 and the sixth light-receiving surface 30s6 of the sixth group 3g6 may appear smaller. This reduces both the amount of reflected light from the fifth group 3g5 directed towards the cockpit 5c of the aircraft 5 in landing approach, generated in response to the irradiation of sunlight SL0, and the amount of reflected light from the sixth group 3g6 directed towards the cockpit 5c of the aircraft 5 in landing approach, generated in response to the irradiation of sunlight SL0. As a result, the degree to which the reflected light of sunlight SL0 from the photovoltaic power generation system 100 is perceived as dazzling by the pilot of the aircraft 5 in landing approach can be reduced.

[0190] In one example shown in Figures 37 and 38, in the first region A1, the first group 3g1 is located further from runway 1 than the fifth group 3g5, but this is not limited to this. For example, in the second region A2, the first group 3g1 may be located further from runway 1 than the sixth group 3g6.

[0191] <2-8. Ninth Embodiment> In each of the above-described embodiments from the first to the eighth, for example, as shown in Figure 39, the group of modules 3g may include a seventh module group (also called the seventh group) 3g7 composed of a seventh number of solar cell modules 3. The seventh number may be any number of two or more.

[0192] Here, for example, as shown in Figure 39, for the seventh group 3g7, the sixth vector V7 is a vector that virtually extends in the direction away from the seventh light-receiving surface 30s7 along the normal direction of each light-receiving surface 30s (also called the seventh light-receiving surface 30s7) of the seventh number of solar cell modules 3. The sixth vector V7 may be, for example, a vector that starts from the reference point (also called the seventh reference point) Pc7 of the seventh group 3g7. The seventh reference point Pc7 may be, for example, the centroid of the seventh group 3g7 when viewed from a plan view.

[0193] Furthermore, as shown in Figure 39, for example, let the seventh vector V76 be a vector that virtually extends from the seventh light-receiving surface 30s7 of the seventh group 3g7 to a second specific position P1b in the control room 6c of the control tower 6. The starting point of the seventh vector V76 may be the same as the starting point of the sixth vector V7.

[0194] Here, for example, if the angle between the sixth vector V7 and the seventh vector V76 (also called the ninth angle θ7) is 90 degrees or greater, the amount of reflected light generated toward the control room 6c at the seventh light-receiving surface 30s7 of the seventh group 3g7 in response to the irradiation of sunlight SL0 can be reduced. This can reduce the occurrence of situations in which air traffic controllers may be dazzled by the reflected light of sunlight SL0. As a result, the ease with which air traffic controllers can guide the aircraft 5 can be improved.

[0195] In one example shown in Figure 39, of the first and second regions A1 and A2 located on either side of the runway 1 in the +Y direction, which is the width direction of the runway 1, both module groups 3g1 (group 1) and 3g7 (group 7) are installed in the first region A1, but this is not limited to this. For example, both module groups 3g1 (group 1) and 3g7 (group 7) may be installed in the second region A2, or the first region 3g1 may be installed in the first region A1 and the second region A2 may be installed in the seventh region 3g7, or the seventh region 3g7 may be installed in the first region A1 and the first region 3g1 may be installed in the second region A2.

[0196] <2-9. Tenth Embodiment> In each of the first to ninth embodiments described above, for example, as shown in Figures 40 and 41, multiple module groups 3g may be connected to the power company's grid 700 at the same interconnection point 86 via a service drop 85. This reduces the number of interconnection points 86 connecting the solar power generation system 100 to the power company's grid 700. As a result, the number of facilities required to realize the interconnection points 86 can be reduced, thereby improving the constructability of the solar power generation system 100. Here, the facilities required to realize one interconnection point 86 may be facilities having an Underground Air Insulated Switch (UGS) and a cable conduit, or facilities having a Pole Mounted Air Insulated Switch (PAS) and a service drop pole, depending on the height restrictions of the buildings at the airport 200.

[0197] Figure 40 is a schematic block diagram showing an example of the general configuration of a photovoltaic power generation system 100 according to the 10th embodiment. In Figure 40, power lines, which are electrical wiring for transmitting electricity, are shown as solid lines, and communication lines for transmitting and receiving signals are shown as dashed lines. The communication lines may be entirely wiring, partially wiring with the remainder performing wireless communication, or entirely performing wireless communication.

[0198] As shown in Figure 40, the photovoltaic power generation system 100 includes, for example, multiple module groups 3g, multiple junction boxes 81, multiple current collection boxes 82, multiple power conditioners (PCS) 83, multiple substations 84, service lines 85, and a control device 89. In one example shown in Figure 40, the photovoltaic power generation system 100 includes eight module groups 3g, eight junction boxes 81, four current collection boxes 82, four power conditioners 83, and two substations 84. More specifically, the eight junction boxes 81 are the first junction box 81a, the second junction box 81b, the third junction box 81c, the fourth junction box 81d, the fifth junction box 81e, the sixth junction box 81f, the seventh junction box 81g, and the eighth junction box 81h. The four current collector boxes 82 are the first current collector box 82a, the second current collector box 82b, the third current collector box 82c, and the fourth current collector box 82d. The four power conditioners 83 are the first power conditioner 83a, the second power conditioner 83b, the third power conditioner 83c, and the fourth power conditioner 83d. The two substations 84 are the first substation 84a and the second substation 84b.

[0199] Each of the multiple module groups 3g includes, for example, multiple solar cell strings. Each of the multiple solar cell strings has two or more solar cell modules connected in series. Each of the multiple solar cell strings can output DC power by generating electricity in response to irradiation from sunlight SL0. The multiple solar cell strings included in one module group 3g are connected to, for example, one junction box 81 via power lines.

[0200] Each of the multiple junction boxes 81 can, for example, collect DC power supplied via power lines from multiple solar cell strings included in one module group 3g and output it to the current collector box 82. Each junction box 81 may have, for example, a reverse current blocking diode, a surge arrester, and a circuit breaker. The reverse current blocking diode includes an element to prevent reverse current flow toward the solar cell string. The surge arrester includes a device to reduce surge voltage that may occur when lightning strikes. The circuit breaker includes a device that opens the circuit when an overcurrent flows. Each junction box 81 may have, for example, a sensor to measure current or a sensor to measure voltage in order to detect abnormalities in each of the multiple solar cell strings. In this case, each junction box 81 may include, for example, a device to transmit a signal related to the measured value measured by the sensor to the control device 89 via a signal line. Also, each junction box 81 may include, for example, a device to receive a signal input from the control device 89 via a signal line. In one example shown in Figure 40, one junction box 81 is connected to one module group 3g via a power line.

[0201] Each of the multiple junction boxes 82 can, for example, combine the DC power supplied via power lines from each of the multiple junction boxes 81 and output it to the power conditioner 83. Each junction box 82 may have, for example, a surge arrester and a circuit breaker. The surge arrester includes a device for reducing surge voltages that may occur when lightning strikes. The circuit breaker includes a device for opening the circuit when an overcurrent flows. In the example shown in Figure 40, each of the two junction boxes 81 is connected to one junction box 82 via power lines. More specifically, the first junction box 81a and the second junction box 81b are each connected to the first junction box 82a. The third junction box 81c and the fourth junction box 81d are each connected to the second junction box 82b. The fifth junction box 81e and the sixth junction box 81f are each connected to the third junction box 82c. The seventh junction box 81g and the eighth junction box 81h are each connected to the fourth junction box 82d. The first junction box 82a can combine the DC power supplied via the power lines from the first junction box 81a and the second junction box 81b and output it to the first power conditioner 83a. The second junction box 82b can combine the DC power supplied via the power lines from the third junction box 81c and the fourth junction box 81d and output it to the second power conditioner 83b. The third junction box 82c can combine the DC power supplied via the power lines from the fifth junction box 81e and the sixth junction box 81f and output it to the third power conditioner 83c. The fourth junction box 82d can combine the DC power supplied via power lines from the seventh junction box 81g and the eighth junction box 81h into a single output and output it to the fourth power conditioner 83d.

[0202] Each of the multiple power conditioners 83 can, for example, convert DC power supplied from the junction box 82 via a power line into AC power and output it to the substation 84. Each power conditioner 83 may have a sensor to measure the input DC power or a sensor to measure the output AC power in order to determine abnormalities in the solar power generation system 100 and the power conditioner 83. In this case, each power conditioner 83 may be equipped with a device that transmits a signal related to the value measured by the sensor (also called a measured value) to the control device 89 via a signal line. Each power conditioner 83 may also be equipped with a device that receives a signal input from the control device 89 via a signal line. Furthermore, each power conditioner 83 may have a function that allows it to appropriately adjust the output AC power in response to a control signal input from the control device 89 via a signal line. In the example shown in Figure 40, one junction box 82 is connected to one power conditioner 83 via a power line. More specifically, the first junction box 82a is connected to the first power conditioner 83a via a power line. The second junction box 82b is connected to the second power conditioner 83b via a power line. The third junction box 82c is connected to the third power conditioner 83c via a power line. The fourth junction box 82d is connected to the fourth power conditioner 83d via a power line. The first power conditioner 83a can convert the DC power supplied from the first junction box 82a via a power line into AC power and output it to the first substation 84a. The second power conditioner 83b can convert the DC power supplied from the second junction box 82b via a power line into AC power and output it to the first substation 84a. The third power conditioner 83c can convert the DC power supplied from the third junction box 82c via a power line into AC power and output it to the second substation 84b. The fourth power conditioner 83d can convert the DC power supplied from the fourth junction box 82d via the power line into AC power and output it to the second substation 84b.

[0203] Each of the multiple substations 84 can, for example, raise the AC power supplied from each of the multiple power conditioners 83 via power lines to a predetermined voltage, combine them, and output them to the power company's grid 700 via power lines. The predetermined voltage is, for example, a voltage that matches the voltage in the power company's grid 700. The predetermined voltage is, for example, a high voltage of 6600 volts (V) or an extra-high voltage of 7000V or more. Here, for example, the power line from the substation 84 to the connection point 86 to the power company's grid 700 is referred to as the service drop 85. From another perspective, for example, the location where the service drop 85, which is a power line extending from the substation 84, connects to the power company's grid 700 is referred to as the connection point 86. In the example shown in Figure 40, two power conditioners 83 are connected to one substation 84 via power lines. More specifically, the first power conditioner 83a and the second power conditioner 83b are connected to the first substation 84a via power lines. The third power conditioner 83c and the fourth power conditioner 83d are connected to the second substation 84b via power lines. The first substation 84a can combine the AC power supplied from the first power conditioner 83a via power lines, which has been raised to a predetermined voltage, with the AC power supplied from the second power conditioner 83b via power lines, which has been raised to a predetermined voltage, and output this combined power to the power company's grid 700 via power lines. The second substation 84b can combine the AC power supplied from the third power conditioner 83c via power lines, which has been raised to a predetermined voltage, with the AC power supplied from the fourth power conditioner 83d via power lines, which has been raised to a predetermined voltage, and output this combined power to the power company's grid 700 via power lines. Furthermore, in the example shown in Figure 40, each substation 84 has two transformers T1. More specifically, the first substation 84a has a first transformer T1a and a second transformer T1b. The second substation 84b has a third transformer T1c and a fourth transformer T1d.The first substation 84a can combine the AC power generated by raising the AC power supplied from the first power conditioner 83a via the power line to a predetermined voltage in the first transformer T1a, and the AC power generated by raising the AC power supplied from the second power conditioner 83b via the power line to a predetermined voltage in the second transformer T1b, and output this combined power to the power company's grid 700 via the service drop 85. The second substation 84b can combine the AC power generated by raising the AC power supplied from the third power conditioner 83c via the power line to a predetermined voltage in the third transformer T1c, and the AC power generated by raising the AC power supplied from the fourth power conditioner 83d via the power line to a predetermined voltage in the fourth transformer T1d, and output this combined power to the power company's grid 700 via the service drop 85.

[0204] The control device 89 is connected to each of the multiple junction boxes 81 and each of the multiple power conditioners 83 in a manner that allows it to send and receive signals via communication lines. The control device 89 may have a function to receive signals relating to measured values ​​such as current and voltage values ​​and to detect one or more abnormalities among abnormalities in the solar cell string, abnormalities in the photovoltaic power generation system 100, and abnormalities in the power conditioner 83. The control device 89 may have a function to transmit, for example, a control signal to each power conditioner 83 via a signal line to adjust the AC power output by the power conditioner 83.

[0205] The control device 89 may have a configuration such as a computer having one or more central processing units (CPUs) and one or more storage devices. The one or more storage devices may include, for example, non-temporary storage media that can be read by the CPU, such as ROM (Read Only Memory) and RAM (Random Access Memory). The storage devices may store, for example, programs. In this case, the various functions of the control device 89 may be realized by the CPU executing programs in the storage devices. The control device 89 may have, for example, multiple CPUs. The control device 89 may have one or more DSPs (Digital Signal Processors). All or some of the functions of the control device 89 may be realized by hardware circuits that do not require software to realize those functions. The storage devices may include non-temporary recording media that can be read by the computer, different from ROM and RAM. The storage devices may include, for example, small hard disk drives and / or SSDs (Solid State Drives).

[0206] Here, for example, a first type of module group 3g and a second type of module group 3g among multiple module groups 3g may be connected to separate transformers T1. More specifically, the first group 3g1 and the second group 3g2 may be connected to separate transformers T1. If this configuration is adopted, power loss can be reduced even if the output current and voltage differ between the first solar cell module 31 constituting the first group 3g1 and the second solar cell module 32 constituting the second group 3g2. Therefore, the amount of power generated in the photovoltaic power generation system 100 can be increased.

[0207] In the example shown in Figure 40, the first group 3g1 may be connected via power lines to each of the first junction box 81a, second junction box 81b, third junction box 81c, and fourth junction box 81d. Similarly, the second group 3g2 may be connected via power lines to each of the fifth junction box 81e, sixth junction box 81f, seventh junction box 81g, and eighth junction box 81h. In this case, multiple first group 3g1 units are connected to two transformers T1 of the first substation 84a, and multiple second group 3g2 units are connected to two transformers T1 of the second substation 84b. In other words, the first group 3g1 and the second group 3g2 are connected to separate transformers T1. This increases the amount of power generated in the solar power generation system 100.

[0208] Here, for example, a first type of module group 3g and a second type of module group 3g from among multiple module groups 3g may be connected to the same transformer T1. More specifically, a first group 3g1 and a second group 3g2 may be connected to the same transformer T1. If this configuration is adopted, it is possible to reduce the number of transformers T1. As a result, the ease of installation of the solar power generation system 100 can be improved.

[0209] Figure 41 is a schematic block diagram showing another example of the general configuration of the photovoltaic power generation system 100 according to the 10th embodiment. The photovoltaic power generation system 100 shown in Figure 41 is based on the photovoltaic power generation system 100 shown in Figure 40, but has a configuration in which the two transformers T1 in the first substation 84a are changed to one transformer T1 (also called the fifth transformer T1e), and the two transformers T1 in the second substation 84b are changed to one transformer T1 (also called the sixth transformer T1f). Here, the first substation 84a can output AC power generated by combining the AC power supplied from the first power conditioner 83a via the power line and the AC power supplied from the second power conditioner 83b via the power line, raising the voltage to a predetermined level in the fifth transformer T1e, to the power company's grid 700 via the service drop 85. The second substation 84b can output AC power generated by combining the AC power supplied from the third power conditioner 83c via the power line and the AC power supplied from the fourth power conditioner 83d via the power line, raising the voltage to a predetermined level in the sixth transformer T1f, and then outputting it to the power company's grid 700 via the service drop 85.

[0210] In the example shown in Figure 41, the first group 3g1 may be connected via power lines to each of the first junction box 81a, second junction box 81b, fifth junction box 81e, and sixth junction box 81f. Also, the second group 3g2 may be connected via power lines to each of the third junction box 81c, fourth junction box 81d, seventh junction box 81g, and eighth junction box 81h. In this case, two first group 3g1s and two second group 3g2s are connected to the fifth transformer T1e of the first substation 84a, and two other first group 3g1s and two other second group 3g2s are connected to the sixth transformer T1f of the second substation 84b. In other words, the first group 3g1s and second group 3g2s are connected to the same transformer T1. This makes it possible to reduce the number of transformers T1. For example, in the example shown in Figure 40, there are four transformers T1, whereas in the example shown in Figure 41, there are only two transformers T1, indicating a reduction in the number of transformers T1. As a result, the ease of installation of the solar power generation system 100 can be improved.

[0211] <2-10. Others> In each of the above-described embodiments from the first to the tenth, for example as shown in Figure 42, the first vector V1 is defined as a vector that virtually extends in a direction away from the first light-receiving surface 30s1 along the normal direction of the light-receiving surface 30s1 of each of the multiple first solar cell modules 31 in the first group 3g1. The first vector V1 may be, for example, a vector that starts from a reference point (first reference point) Pc1 of the first group 3g1. The first reference point Pc1 may be, for example, the centroid of the first group 3g1 when viewed from a plan view. Furthermore, the eighth vector V15 is defined as a vector that extends from the first light-receiving surface 30s1 of the first group 3g1 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing configuration. The starting point of the eighth vector V15 may be the same as the starting point of the first vector V1. Here, for example, if the angle θ15 formed by the first vector V1 and the eighth vector V15 is 90 degrees or more, the likelihood of specular reflected light RL1 generated by the first group 3g1 in response to the irradiation of sunlight SL0 entering the cockpit 5c of the aircraft 5 in landing approach decreases. Therefore, even if the first solar cell module 31, which has a higher conversion efficiency than the second solar cell module 32, is installed, the likelihood of the degree to which the reflected light of sunlight SL0 in the solar power generation system 100 is perceived as dazzling by the pilot of the aircraft 5 in landing approach decreases. Thus, for example, by arranging a larger number of first solar cell modules 31, it becomes possible to increase the amount of power generated in the solar power generation system 100.

[0212] In one example shown in Figure 42, the first group 3g1 is installed in the second region A2 of the first region A1 and the second region A2, which are located on either side of the runway 1 in the direction of the +Y direction, which is the width direction of the runway 1. However, it is not limited to this. For example, the first group 3g1 may be installed in the first region A1.

[0213] In each of the above-described embodiments from the first to the tenth, for example as shown in Figure 43, the ninth vector V2 is defined as a vector that virtually extends in the direction away from the light-receiving surface 30s along the normal direction of the light-receiving surface 30s of each of the two or more solar cell modules 3 for the second group 3g2. The ninth vector V2 may be, for example, a vector that starts from the reference point (second reference point) Pc2 of the second group 3g2. The second reference point Pc2 may be, for example, the centroid of the second group 3g2 when viewed from above. Furthermore, the tenth vector V25 is defined as a vector that extends from the light-receiving surface 30s of the second group 3g2 to a first specific position P1a in the cockpit 5c of the aircraft 5 in landing configuration. The starting point of the tenth vector V25 may be the same as the starting point of the ninth vector V2. Here, for example, if the angle θ25 formed by the ninth vector V2 and the tenth vector V25 is less than 90 degrees, there is a high probability that specular reflected light RL1 generated by the second group 3g2 in response to the irradiation of sunlight SL0 will enter the cockpit 5c of the aircraft 5 in landing approach. However, since the second group 3g2 includes one or more second solar cell modules 32, each having a second light-receiving surface 30s2 with a lower light reflectivity than the first light-receiving surface 30s1, the degree to which the pilot of the aircraft 5 in landing approach perceives glare from the reflected light of sunlight SL0 from the light-receiving surface 30s can be reduced to an acceptable level. As a result, the glare caused by the reflection of sunlight SL0 can be reduced with respect to the solar power generation system 100.

[0214] In each of the above embodiments, for example, the retinal irradiance Er and visual angle ω corresponding to the estimated irradiance E1 were calculated for each module group 3g, but this is not limited to this. For example, the retinal irradiance Er and visual angle ω corresponding to the estimated irradiance E1 may be calculated for each solar cell module 3 constituting the module group 3g. In this case, for example, a representative point of the solar cell module 3 may be used for each solar cell module 3 instead of a representative point relating to a plurality of light-receiving surfaces 30s. For example, the centroid of the solar cell module 3 viewed from a planar perspective may be applied as the representative point of the solar cell module 3. Here, for example, for each solar cell module 3, it may be evaluated whether the retinal irradiance Er, as the estimated irradiance E1, is less than or equal to a predetermined critical irradiance Et when the sun 900 performs its annual diurnal motion. Furthermore, for example, during the design phase of the photovoltaic power generation system 100, each of the multiple solar cell modules 3 constituting one module group 3g may be virtually designated as a first solar cell module 31. For one or more solar cell modules 3 in one module group 3g, if there is a time when the retinal irradiance Er, as estimated irradiance E1, exceeds a critical irradiance Et, as a predetermined irradiance, when the sun 900 performs its diurnal motion throughout the year, that module group 3g may be designed as a second group 3g2. Alternatively, for example, during the design phase of the photovoltaic power generation system 100, if each of the multiple solar cell modules 3 is virtually designated as a first solar cell module 31, then each of the one or more solar cell modules 3 among the multiple solar cell modules 3 that causes the estimated value of the irradiance of reflected light incident at a specific position P1 in response to the reflection of sunlight SL0 (estimated irradiance) to be greater than a predetermined irradiance when the sun 900 performs its diurnal motion throughout the year may be designated as a second solar cell module 32.

[0215] In each of the above embodiments, the retinal irradiance Er was calculated as an estimated value of the irradiance of specularly reflected light RL1 incident on the retina 7e5 of the subject's eyeball 7e at a specific position P1, but is not limited to this. The retinal irradiance Er may be calculated by various other calculations. For example, the retinal irradiance Er may be calculated as an estimated value of the irradiance of diffusely reflected light incident on the retina 7e5 of the subject's eyeball 7e at a specific position P1 after sunlight SL0 undergoes diffuse reflection at multiple light-receiving surfaces 30s. In this case, for example, the retinal irradiance Er may be used as the estimated irradiance E1, or the calculated value of irradiance calculated based on the retinal irradiance Er may be used as the estimated irradiance E1. Here, an embodiment may be adopted in which the calculated value of irradiance is calculated by multiplying the retinal irradiance Er by a coefficient. For example, a safety factor may be applied as the coefficient. For example, a value greater than 1 and less than or equal to 3 may be applied as the safety factor.

[0216] In each of the embodiments described above, the estimated irradiance E1 was calculated, but is not limited to this. The estimated irradiance E1 may be, for example, the illuminance actually measured using a measuring device in the cockpit 5c of the aircraft 5 or the control room 6c of the control tower 6 (also called the measured illuminance), or it may be calculated based on this measured illuminance. Furthermore, the measured illuminance may be obtained, for example, by measurement using a measuring device mounted on an unmanned aerial vehicle such as a drone.

[0217] In each of the embodiments described above, for example, in the first embodiment, an example was given in which the first group 3g1 consists only of a plurality of first solar cell modules 31, but the invention is not limited to this. For example, the first group 3g1 may include solar cell modules 3 different from the first solar cell modules 31. In this case, a configuration may be adopted in which the proportion of the first solar cell modules 31 in two or more solar cell modules 3 constituting the first group 3g1 is greater than the proportion of the first solar cell modules 31 in two or more solar cell modules 3 constituting the second group 3g2.

[0218] In each of the above embodiments, for example, if the second sealing layer 304 is light-transmitting, the portion of the back surface protective member 305 on the light-receiving surface 30s side may be made black. This can reduce the amount of reflected light generated in the solar cell module 3 in response to irradiation by sunlight SL0.

[0219] In each of the above embodiments, for example, the light-transmitting member 301 may be a glass plate having an uneven surface, such as an anti-reflective coating and embossing, applied to the surface opposite to the photoelectric conversion unit 303 (first surface) and the surface on the photoelectric conversion unit 303 side (also called the second surface).

[0220] In each of the above embodiments, for example, the number of first wiring materials W1 that electrically connect adjacent solar cells 303c among the plurality of solar cells 303c may be 4 to 15.

[0221] In each of the above embodiments, for example, the plurality of solar cells 303c may include a plurality of substantially rectangular solar cells formed by dividing a substantially square solar cell.

[0222] In each of the above embodiments, for example, the light-transmitting member 301 may be a film-like member. In this case, for example, a plate-like member may be applied to the back surface protective member 305 in order to maintain the rigidity of the solar cell module 3. For example, the material of the plate-like back surface protective member 305 may be glass or a resin such as acrylic or polycarbonate. For example, a weather-resistant resin may be applied to the material of the film-like light-transmitting member 301. Weather resistance means, for example, the property of being resistant to deterioration such as deformation, discoloration, and degradation when used outdoors. Here, the weather-resistant resin includes, for example, a fluorine-based resin. Fluorine-based resins include, for example, fluorinated ethylene propylene copolymer (FEP), ethylene tetrafluoroethylene copolymer (ETFE), and ethylene chlorotrifluoroethylene copolymer (ECTFE). Here, for example, the light-transmitting member 301 may be composed of two or more layers of weather-resistant resin. In this case, the fluorine-based resin applied to the translucent member 301 may be, for example, two or more types of resin. For this reason, for example, an embodiment in which the fluorine-based resin applied to the translucent member 301 includes at least one resin from among FEP, ETFE, and ECTFE is conceivable. Furthermore, the thickness of the translucent member 301 may be, for example, about 0.05 mm to 0.5 mm.

[0223] In each of the above embodiments, for example, if the solar power generation system 100 is installed in the Southern Hemisphere, the light-receiving surface 30s may be inclined with respect to the horizontal plane so as to face diagonally upward in the north direction, where the sun 900 is in the meridian direction. In other words, the light-receiving surface 30s may be inclined with respect to the horizontal plane so as to be located lower as one moves further north.

[0224] In each of the above embodiments, for example, the installation angle and installation orientation that define the direction in which the light-receiving surface 30s faces may be the same or different among multiple module groups 3g. In the Northern Hemisphere, the light-receiving surface 30s may face south or not. In the Southern Hemisphere, the light-receiving surface 30s may face north or not. Also, for example, the light-receiving surface 30s may not be inclined with respect to the horizontal plane.

[0225] In each of the above embodiments, for example, the reflected light incident on a specific position P1 (first specific position P1a) in the cockpit 5c of the aircraft 5 in flight in response to the reflection of sunlight SL0 from the multiple solar cell modules 3 may be replaced with reflected light incident on the cockpit 5c of the aircraft 5 in flight in response to the reflection of sunlight SL0 from the multiple solar cell modules 3. Even in this case, the degree to which a person in the cockpit 5c of the aircraft 5 in flight perceives the reflected light of sunlight SL0 from the light-receiving surface 30s as dazzling can be reduced to an acceptable range. The reflected light incident on the cockpit 5c of the aircraft 5 in flight enters the interior of the cockpit 5c, for example, by passing through the windows of the cockpit 5c. Therefore, the illuminance of the reflected light incident on the cockpit 5c of the aircraft 5 in flight can also be evaluated by the illuminance of the reflected light irradiated onto the windows of the cockpit 5c. Furthermore, it is assumed that the illuminance of the reflected light irradiated onto the windows of the cockpit 5c is substantially the same as the illuminance of the reflected light irradiated onto the outer wall surrounding the windows of the cockpit 5c. Therefore, the illuminance of reflected light incident on the cockpit 5c of the aircraft 5 in flight can also be evaluated by the illuminance of reflected light illuminating the outer wall of the cockpit 5c. Thus, the reflected light incident on the cockpit 5c of the aircraft 5 in flight may be, for example, reflected light incident on the interior of the cockpit 5c of the aircraft 5 in flight, or reflected light illuminating the outer part of the cockpit 5c of the aircraft 5 in flight. The outer part of the cockpit 5c of the aircraft 5 in flight may be, for example, the windows of the cockpit 5c, or the outer wall of the cockpit 5c. In other words, the outer part of the cockpit 5c of the aircraft 5 in flight may be the part that separates the cockpit 5c from the space outside the aircraft 5. This separating part may include, for example, windows, or it may include an outer wall.

[0226] Furthermore, in each of the above embodiments, for example, the reflected light incident on a specific position P1 (second specific position P1b) in the control room 6c of the control tower 6 in response to the reflection of sunlight SL0 from the multiple solar cell modules 3 may be replaced with reflected light incident on the control room 6c of the control tower 6 in response to the reflection of sunlight SL0 from the multiple solar cell modules 3. Even in this case, the degree to which the subject in the control room 6c of the control tower 6 perceives the reflected light of sunlight SL0 from the light-receiving surface 30s as dazzling can be reduced to an acceptable range. The reflected light incident on the control room 6c of the control tower 6 passes through the windows of the control room 6c and enters the interior of the control room 6c. For this reason, the illuminance of the reflected light incident on the control room 6c of the control tower 6 can also be evaluated by the illuminance of the reflected light irradiated onto the windows of the control room 6c. It is also assumed that the illuminance of the reflected light irradiated onto the windows of the control room 6c is substantially the same as the illuminance of the reflected light irradiated onto the outer walls surrounding the windows of the control room 6c. Therefore, the illuminance of reflected light incident on the control room 6c of the control tower 6 can also be evaluated by the illuminance of reflected light illuminating the outer wall of the control room 6c. Thus, the reflected light incident on the control room 6c of the control tower 6 may be, for example, reflected light incident on the interior of the control room 6c of the control tower 6, or reflected light illuminating the outer part of the control room 6c of the control tower 6. The outer part of the control room 6c of the control tower 6 may be, for example, a window of the control room 6c, or the outer wall of the control room 6c. In other words, the outer part of the control room 6c of the control tower 6 may be the part that separates the control room 6c from the space outside the control tower 6. This separating part may include, for example, a window, or it may include an outer wall.

[0227] Therefore, in each of the above embodiments, when the sun 900 performs its year-round diurnal motion, the estimated value of the irradiance of the reflected light incident on one or more specific positions P1 in space in response to the reflection of sunlight SL0 from the multiple solar cell modules 3 (estimated irradiance) was less than or equal to a predetermined irradiance, but is not limited to this. In each of the above embodiments, for example, the estimated irradiance may be the estimated value of the irradiance of the reflected light incident on the cockpit 5c of an aircraft 5 in flight or the control room 6c of an air traffic control tower 6 in response to the reflection of sunlight SL0 from the multiple solar cell modules 3 when the sun 900 performs its year-round diurnal motion. In other words, in each of the above embodiments, when the sun 900 performs its year-round diurnal motion, the estimated value of the irradiance of the reflected light incident on the cockpit 5c of an aircraft 5 in flight or the control room 6c of an air traffic control tower 6 in response to the reflection of sunlight SL0 from the multiple solar cell modules 3 (estimated irradiance) may be less than or equal to a predetermined irradiance. Even if this configuration is adopted, the glare caused by the reflection of sunlight SL0 can be reduced. From another perspective, in the solar power generation system 100, the decrease in power generation can be reduced while reducing glare caused by the reflection of sunlight SL0. Furthermore, the statement that the estimated irradiance is below a predetermined irradiance when the sun 900 performs its yearly diurnal motion means that the state in which the estimated irradiance is below a predetermined irradiance is maintained when the sun 900 performs its yearly diurnal motion.

[0228] In each of the above embodiments, for example, the location where some or all of the multiple solar cell modules 3 constituting the solar power generation system 100 are installed may be replaced with a location outside the airport 200 premises. A location outside the airport 200 premises may include, for example, mountains, hills, and bodies of water outside the airport 200.

[0229] In each of the above embodiments, for example, the control room 6c of the control tower 6 may be replaced with a space within a building surrounding the airport 200. In this case, the degree to which a person in the space within the building surrounding the airport 200 feels glare from the reflected sunlight SL0 from the light-receiving surface 30s can be reduced to an acceptable level. As a result, the glare caused by the reflection of sunlight SL0 can be reduced with respect to the photovoltaic power generation system 100.

[0230] Note that, in each of the above embodiments, for example, the location where some or all of the plurality of solar cell modules 3 constituting the photovoltaic power generation system 100 are installed may be replaced with another location such as the roof or side wall of a building or an idle land. Here, the control room 6c of the control tower may be replaced with a space in a building around the photovoltaic power generation system 100. In this case, the degree to which a person in a space in a building around the photovoltaic power generation system 100 feels the reflected light of sunlight SL0 from the light-receiving surface 30s is dazzling can be reduced to within an allowable range. As a result, for the photovoltaic power generation system 100, glare caused by reflection of sunlight SL0 can be reduced.

[0231] As described above, the photovoltaic power generation system 100 has been described in detail; however, the above description is an example in all aspects, and the present disclosure is not limited thereto. In addition, the various examples described above can be applied in combination as long as they do not contradict each other. It is understood that countless examples not illustrated can be assumed without departing from the scope of the present disclosure.

[0232] The present disclosure includes the following contents.

[0233] In one embodiment, (1) a photovoltaic power generation system comprises a plurality of solar cell modules respectively installed on land along a longitudinal direction of a runway or landing strip in an airport, the plurality of solar cell modules have a plurality of groups including a first group composed of a plurality of first solar cell modules and a second group composed of two or more solar cell modules including one or more second solar cell modules, a light reflectance at a light-receiving surface of each of the one or more second solar cell modules is smaller than a light reflectance at a light-receiving surface of each of the plurality of first solar cell modules, and when the sun performs diurnal motion throughout the year, an estimated irradiance of reflected light that enters a cockpit of an aircraft in flight or a control room of a control tower in accordance with reflection of sunlight by the plurality of solar cell modules is equal to or less than a predetermined irradiance.

[0234] (2) In the photovoltaic power generation system of (1) above, the estimated irradiance may be the estimated irradiance of reflected light incident on a specific position in one or more spaces selected from the cockpit of an aircraft in flight and the control room of a control tower in accordance with the reflection of sunlight by the plurality of solar cell modules.

[0235] (3) In the photovoltaic power generation system of (1) or (2) above, the aircraft in flight may include an aircraft in a landing configuration for landing on the runway.

[0236] (4) In the photovoltaic power generation system according to any one of (1) to (3) above, when each of the plurality of solar cell modules is virtually regarded as the first solar cell module, when the sun performs the diurnal motion throughout the year, each of the one or more solar cell modules that make the estimated irradiance of the reflected light among the plurality of solar cell modules larger than the predetermined irradiance may be the second solar cell module.

[0237] (5) In the photovoltaic power generation system of (2) above, the plurality of groups include a group A configured from a first number of solar cell modules and a group B configured from a second number of solar cell modules, and when each of the plurality of solar cell modules is virtually regarded as the first solar cell module, the estimated irradiance of the reflected light incident on the retina of an eyeball at the specific position at a first viewing angle ω1[rad] in accordance with the reflection of sunlight in the group A is defined as E11[W / m 2 , and the estimated irradiance of the reflected light incident on the retina of an eyeball at the specific position at a second viewing angle ω2[rad] in accordance with the reflection of sunlight in the group B is defined as E12[W / m 2 , and the predetermined irradiance calculated by the formula Et1=0.359 / ω1 1.77 using the first viewing angle ω1[rad] is defined as Et1[W / m 2 , and the predetermined irradiance calculated by the formula Et2=0.359 / ω2 1.77The predetermined irradiance calculated by the formula is the second critical irradiance, Et2[W / m 2 In this case, if, during the year-round diurnal motion of the sun, there is a time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, then group A is the second group and group B is the first group. If, during the year-round diurnal motion of the sun, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is a time when the second estimated irradiance exceeds the second critical irradiance, then group A is the first group and group B is the second group.

[0238] (6) In the photovoltaic power generation system described in (2) above, the plurality of groups includes a group A composed of a first number of solar cell modules and a group B composed of a second number of solar cell modules, and when each of the plurality of solar cell modules is virtually considered to be the first solar cell module, the estimated irradiance of the reflected light incident on the retina of the eyeball at a first viewing angle ω1 [rad] at the specific position in response to the reflection of sunlight in group A is the first estimated irradiance E11 [W / m 2 The estimated irradiance of the reflected light incident on the retina of the eyeball at a specific position at a second visual angle ω2 [rad] in response to the reflection of sunlight in group B is the second estimated irradiance, E12 [W / m 2 Let ] and use the first viewing angle ω1 [rad] to get Et1 = 0.359 / ω1 1.77 The predetermined irradiance calculated by the formula is the first critical irradiance, Et1 [W / m 2 Let ] and use the second viewing angle ω2 [rad] to get Et2 = 0.359 / ω2 1.77 The predetermined irradiance calculated by the formula is the second critical irradiance, Et2[W / m 2In this case, when the sun performs its diurnal motion throughout the year, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, and the minimum value of the first difference obtained by subtracting the first estimated irradiance from the first critical irradiance is greater than the minimum value of the second difference obtained by subtracting the second estimated irradiance from the second critical irradiance, then group A is the first group and group B is the second group. When the sun performs its diurnal motion throughout the year, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, and the minimum value of the first difference is smaller than the minimum value of the second difference, then group A is the second group and group B is the first group.

[0239] (7) In the solar power generation system described in (2) above, the aircraft in flight includes an aircraft in a landing approach for landing on the runway, and the first angle formed by a first imaginary line connecting the specific position in the cockpit of the aircraft in the landing approach to the centroid of the runway target point marker, and a second imaginary line connecting the specific position in the cockpit of the aircraft in the landing approach to the first reference point of the first group, may be greater than the second angle formed by the first imaginary line and a third imaginary line connecting the specific position in the cockpit of the aircraft in the landing approach to the second reference point of the second group.

[0240] (8) In the solar power generation system described in (3) above, the first distance from the centroid of the runway target point marker to the first group may be greater than the second distance from the centroid to the second group.

[0241] (9) In the photovoltaic power generation system described in (3) above, the runway has a first target point marker and a second target point marker different from the first target point marker, the distance from the centroid of the first target point marker to the first reference point of the first group is the third distance, the distance from the centroid of the second target point marker to the first reference point is the fourth distance, the distance from the centroid of the first target point marker to the second reference point of the second group is the fifth distance, and the distance from the centroid of the second target point marker to the second reference point is the sixth distance, and either the fifth distance or the sixth distance may be smaller than either the third distance or the fourth distance.

[0242] (10) In the photovoltaic power generation system described in (9) above, the plurality of groups include a second A group and a second B group, each composed of two or more solar cell modules, each including one or more second solar cell modules, and in the longitudinal direction, the second A group and the second B group are positioned on either side of the first group, the distance from the centroid of the first target point marker to the second A reference point of the second A group is the fifth A distance, the distance from the centroid of the second target point marker to the second A reference point is the sixth A distance, the distance from the centroid of the first target point marker to the second B reference point of the second B group is the fifth B distance, and the distance from the centroid of the second target point marker to the second B reference point is the sixth B distance, and either the fifth A distance or the sixth A distance may be smaller than either the third distance or the fourth distance, and either the fifth B distance or the sixth B distance may be smaller than either the third distance or the fourth distance.

[0243] (11) In the photovoltaic power generation system described in (3) above, the land includes a first area and a second area, the first area and the second area are located on either side of the runway or the landing strip in the width direction of the runway perpendicular to the longitudinal direction, the first group is installed in the second area, and the second group is installed in the first area, and when the sun performs its diurnal motion throughout the year, the first A reflected light having a peak intensity among the reflected light of the sun generated at the light-receiving surface of each of the plurality of first solar cell modules in the first group is greater than the intensity of the reflected light generated by diffuse reflection. There is no time when the first passing region through which the second A reflected light, which has an intensity of a predetermined intensity or greater that is close to the peak intensity, passes, and the landing flight path through which the aircraft flies toward the centroid of the target point marker on the runway, and there may be time when the second passing region through which the second B reflected light, which has an intensity of a predetermined intensity or greater that is closer to the peak intensity of the first B reflected light, and the intensity of the reflected light generated by diffuse reflection, passes, when the sun performs its diurnal motion throughout the year, as the sun moves.

[0244] (12) In any one of the photovoltaic power generation systems described in (1) to (11) above, the first group includes a row of a first number of rows of solar cell modules, each consisting of two or more solar cell modules, and the second group includes a row of a second number of rows of solar cell modules, each consisting of two or more solar cell modules, wherein the first row spacing in the row of the first number of rows of solar cell modules in a plan view is less than or equal to the first row spacing, the second row spacing in the row of the second number of rows of solar cell modules in a plan view is less than or equal to the first row spacing, and the distance between the first group and the second group in a plan view may be greater than or equal to the second row spacing, which is greater than the first row spacing.

[0245] (13) In any one of the solar power generation systems described in (1) to (10) above, the land includes a first area and a second area, the first area and the second area are located on either side of the runway or the landing strip in the width direction of the runway perpendicular to the longitudinal direction, the first group is installed in the first area, and the plurality of groups includes a third group installed in the first area and consisting of a third number of solar cell modules, the third group is located closer to the runway than the first group, and with respect to the first group, the plurality of first If the widthwise component of a first vector that virtually extends in the direction away from the light-receiving surface along the normal direction of each light-receiving surface of a solar cell module is defined as the first horizontal vector, and for the third group, the widthwise component of a second vector that virtually extends in the direction away from the light-receiving surface along the normal direction of each light-receiving surface of the third number of solar cell modules is defined as the second horizontal vector, then the direction of the first horizontal vector and the direction of the second horizontal vector may be opposite, and the second horizontal vector may extend in the direction away from the runway.

[0246] (14) In any one of the solar power generation systems described in (1) to (10) above, the land includes a first area and a second area, the first area and the second area are located on either side of the runway or the landing strip in the width direction of the runway perpendicular to the longitudinal direction, the first group is installed in the second area, and the plurality of groups include a fourth group installed in the first area and consisting of a fourth number of solar cell modules, and for the first group, the normal direction of the light-receiving surface of each of the plurality of first solar cell modules If the widthwise component of the first vector that virtually extends in a direction away from the light-receiving surface along the normal direction of the light-receiving surface of each of the fourth number of solar cell modules is defined as the first horizontal vector, then the widthwise component of the third vector that virtually extends in a direction away from the light-receiving surface along the normal direction of the light-receiving surface of each of the fourth number of solar cell modules is defined as the third horizontal vector, then the direction of the first horizontal vector and the direction of the third horizontal vector may be opposite, and both the direction of the first horizontal vector and the third horizontal vector may be away from the runway.

[0247] (15) In any one of the solar power generation systems described in (1) to (10) above, the land includes a first area and a second area, the first area and the second area are located on either side of the runway or the landing strip in the width direction of the runway perpendicular to the longitudinal direction, and the plurality of groups include a fifth group installed in the first area and consisting of a fifth number of solar cell modules, and a sixth group installed in the second area and consisting of a sixth number of solar cell modules, and for the fifth group, the fifth number of solar cell modules If the widthwise component of the fourth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface is defined as the fourth horizontal vector, and for the sixth group, the widthwise component of the fifth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the sixth number of solar cell modules is defined as the fifth horizontal vector, then the direction of the fourth horizontal vector and the direction of the fifth horizontal vector may be opposite, and both the direction of the fourth horizontal vector and the fifth horizontal vector may be away from the runway.

[0248] (16) In any one of the photovoltaic power generation systems described in (2) and (5) to (7) above, the plurality of groups includes a seventh group consisting of a seventh number of solar cell modules, wherein the angle between a sixth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the seventh number of solar cell modules and a seventh vector that virtually extends from the light-receiving surface to the specific position in the control room of the control tower is 90 degrees or more.

[0249] (17) In any one of the photovoltaic power generation systems described in (2), (5) to (7) and (16) above, the one or more spaces may include the control room of the control tower, and the particular location may include the viewpoint of an air traffic controller seated in one or more of the following seats: the control clearance transmission seat, the ground control seat, and the airfield control seat.

[0250] (18) In the photovoltaic power generation system according to any one of (1) to (17) above, the plurality of groups may be connected to the grid of an electric power company at the same interconnection point via a lead-in wire. Description of Reference Signs

[0251] 1 Runway 100 Photovoltaic power generation system 1a Target point marker 1a1 First target point marker 1a2 Second target point marker 2 Landing strip 200 Airport 3 Solar cell module 30s Light-receiving surface 30s1 First light-receiving surface 30s2 Second light-receiving surface 30s3 Third light-receiving surface 30s4 Fourth light-receiving surface 30s5 Fifth light-receiving surface 30s6 Sixth light-receiving surface 30s7 Seventh light-receiving surface 31 First solar cell module 32 Second solar cell module 3La First module row 3Lb Second module row 3g Module group 3g1 First group (first module group) 3g2 Second group (second module group) 3g2a 2A group 3g2b 2B group 3g3 Third group (third module group) 3g4 Fourth group (fourth module group) 3g5 Fifth group (fifth module group) 3g6 Sixth group (sixth module group) 3g7 Seventh group (seventh module group) 3ga Group A 3gb Group B 5 Aircraft 5c Cockpit 6 Control tower 6c Control room 700 power company grids 7e eyeball 7e5 retina 85 Siding 86 interconnection point 900 sun A1 1st area A2 2nd area Ap1 1st passage area Ap2 2nd passage area Ds1 1st distance Ds2 2nd distance Ds3 3rd distance Ds4 4th distance Ds5 5th distance Ds5a 5th A distance Ds5b 5th B distance Ds6 6th distance Ds6a 6A distance Ds6b 6th B distance E1 Estimated Irradiance E11 First Estimated Irradiance E1b Second estimated irradiance Et critical irradiance Et1 1st critical irradiance Et2 2nd critical irradiance Fr1 Landing Flight Path Level 1, First Virtual Line Lv2 Second Virtual Line Level 3, Third Virtual Line P1 Specific location Pc0 Landing Reference Point Pc0a First Landing Reference Point Pc0b Second Landing Reference Point Pc1 1st reference point Pc2 2nd reference point Pc2a 2nd A reference point Pc2b 2nd B reference point Pc3 3rd reference point Pc4 4th reference point Pc5 5th reference point Pc6 6th reference point Pc7 7th reference point RL1 Specular reflection light SL0 solar light T1 Transformer Th1 prescribed strength V1 First vector V15 8th vector V1h First horizontal vector V2 Second vector V25 9th vector V3 Second vector V3h Second horizontal vector V4 Third vector V4h Third horizontal vector V5 4th vector V5h 4th horizontal vector V6 Fifth vector V6h 5th horizontal vector V7 Sixth vector V76, the 7th vector d1 First interval d2 2nd interval

Claims

1. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The estimated irradiance is the estimated irradiance of reflected light incident on a specific location in one or more spaces, such as the cockpit of an aircraft in flight and the control room of an air traffic control tower, in response to the reflection of sunlight by the plurality of solar cell modules. The aforementioned plurality of groups include group A, which consists of a first number of solar cell modules, and group B, which consists of a second number of solar cell modules. When each of the plurality of solar cell modules is virtually designated as the first solar cell module, the estimated irradiance of the reflected light incident on the retina of the eye at a specific position at a first visual angle ω1 [rad] in response to the reflection of sunlight in group A is defined as the first estimated irradiance E11 [W / m²], the estimated irradiance of the reflected light incident on the retina of the eye at a specific position at a second visual angle ω2 [rad] in response to the reflection of sunlight in group B is defined as the second estimated irradiance E12 [W / m²], the predetermined irradiance calculated using the first visual angle ω1 [rad] by the formula Et1 = 0.359 / ω1 1.77 is defined as the first critical irradiance Et1 [W / m²], and the formula Et2 = 0.359 / ω2 1.77 using the second visual angle ω2 [rad] is defined as Et2 = 0.359 / ω2 1.77 When the predetermined irradiance calculated by the formula is set to the second critical irradiance, Et2 [W / m²], If, during the year-round diurnal motion of the sun, there is a time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, then group A is group 2 and group B is group 1. A photovoltaic power generation system in which, when the sun performs its annual diurnal motion, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is a time when the second estimated irradiance exceeds the second critical irradiance, in which case group A is the first group and group B is the second group.

2. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The estimated irradiance is the estimated irradiance of reflected light incident on a specific location in one or more spaces, such as the cockpit of an aircraft in flight and the control room of an air traffic control tower, in response to the reflection of sunlight by the plurality of solar cell modules. The aforementioned plurality of groups include group A, which consists of a first number of solar cell modules, and group B, which consists of a second number of solar cell modules. When each of the plurality of solar cell modules is virtually designated as the first solar cell module, the estimated irradiance of the reflected light incident on the retina of the eye at a specific position at a first visual angle ω1 [rad] in response to the reflection of sunlight in group A is defined as the first estimated irradiance E11 [W / m²], the estimated irradiance of the reflected light incident on the retina of the eye at a specific position at a second visual angle ω2 [rad] in response to the reflection of sunlight in group B is defined as the second estimated irradiance E12 [W / m²], the predetermined irradiance calculated using the first visual angle ω1 [rad] by the formula Et1 = 0.359 / ω1 1.77 is defined as the first critical irradiance Et1 [W / m²], and the formula Et2 = 0.359 / ω2 1.77 using the second visual angle ω2 [rad] is defined as Et2 = 0.359 / ω2 1.77 When the predetermined irradiance calculated by the formula is set to the second critical irradiance, Et2 [W / m²], If, during the year-round diurnal motion of the sun, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, and the minimum value of the first difference obtained by subtracting the first estimated irradiance from the first critical irradiance is greater than the minimum value of the second difference obtained by subtracting the second estimated irradiance from the second critical irradiance, then group A is the first group and group B is the second group. A photovoltaic power generation system in which, during the year-round diurnal motion of the sun, there is no time when the first estimated irradiance exceeds the first critical irradiance and there is no time when the second estimated irradiance exceeds the second critical irradiance, and if the minimum value of the first difference is smaller than the minimum value of the second difference, then group A is the second group and group B is the first group.

3. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The estimated irradiance is the estimated irradiance of reflected light incident on a specific location in one or more spaces, such as the cockpit of an aircraft in flight and the control room of an air traffic control tower, in response to the reflection of sunlight by the plurality of solar cell modules. The aircraft in flight includes an aircraft in a landing approach for landing on the runway. A solar power generation system wherein the first angle formed by a first virtual line connecting the specific position in the cockpit of the aircraft in landing approach and the centroid of the runway target point marker, and a second virtual line connecting the specific position in the cockpit of the aircraft in landing approach and the first reference point of the first group, is greater than the second angle formed by the first virtual line and a third virtual line connecting the specific position in the cockpit of the aircraft in landing approach and the second reference point of the second group.

4. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aircraft in flight includes an aircraft in a landing approach for landing on the runway. A solar power generation system in which the first distance from the centroid of a runway target point marker to the first group is greater than the second distance from the centroid to the second group.

5. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aircraft in flight includes an aircraft in a landing approach for landing on the runway. The runway has a first target point marker and a second target point marker different from the first target point marker. The distance from the centroid of the first target point marker to the first reference point of the first group is the third distance. The distance from the centroid of the second target point marker to the first reference point is the fourth distance. The distance from the centroid of the first target point marker to the second reference point of the second group is the fifth distance. The distance from the centroid of the second target point marker to the second reference point is the sixth distance. A solar power generation system in which either the fifth distance or the sixth distance is smaller than either the third distance or the fourth distance.

6. A solar power generation system according to claim 5, The plurality of groups includes a second group A and a second group B, each composed of two or more solar cell modules, each including one or more second solar cell modules. In the longitudinal direction, the second group A and the second group B are located on either side of the first group. The distance from the centroid of the first target point marker to the second A reference point of the second A group is the fifth A distance. The distance from the centroid of the second target point marker to the second A reference point is the sixth A distance. The distance from the centroid of the first target point marker to the second B reference point of the second B group is the fifth B distance. The distance from the centroid of the second target point marker to the second B reference point is the sixth B distance. Either the 5A distance or the 6A distance is smaller than either the 3rd distance or the 4th distance. A solar power generation system in which either the 5B distance or the 6B distance is smaller than either the 3rd distance or the 4th distance.

7. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aircraft in flight includes an aircraft in a landing approach for landing on the runway. The aforementioned land includes the first area and the second area, The first region and the second region are located in the width direction of the runway, perpendicular to the longitudinal direction, with the runway or the landing strip in between. The first group is installed in the second region, The second group is installed in the first region, When the sun performs its diurnal motion throughout the year, there is no time when the first passing region, through which the first A reflected light having a peak intensity and the second A reflected light having an intensity of a predetermined intensity or greater that is closer to the peak intensity of the first A reflected light than the intensity of the reflected light generated by diffuse reflection, pass, and the landing flight path through which the aircraft flies toward the centroid of the target point marker on the runway, pass. A solar power generation system in which, as the sun performs its diurnal motion throughout the year, there is a time when the landing flight path and the second passing region through which the first B reflected light, which has a peak intensity among the reflected light of the sunlight generated at the light-receiving surface of each of the two or more solar cell modules in the second group, and the second B reflected light, which has an intensity of a predetermined intensity or greater that is closer to the peak intensity of the first B reflected light than the intensity of the reflected light generated by diffuse reflection, overlap.

8. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The first group includes a row of solar cell modules with a first number of rows, each row being composed of two or more solar cell modules. The second group includes a second row of solar cell modules, each row consisting of two or more solar cell modules. The first column spacing, which is the spacing between columns in the first row of solar cell modules when viewed from above, is less than or equal to the first spacing. The second column spacing, which is the spacing between columns in the second row of solar cell modules when viewed from above, is less than or equal to the first spacing. A photovoltaic power generation system in which the distance between the first group and the second group when viewed from above is greater than or equal to the second distance, which is greater than the first distance.

9. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aforementioned land includes the first area and the second area, The first region and the second region are located in the width direction of the runway, perpendicular to the longitudinal direction, with the runway or the landing strip in between. The first group is installed in the first region, The plurality of groups includes a third group which is installed in the first region and consists of a third number of solar cell modules, The third group is located closer to the runway than the first group, A photovoltaic power generation system in which, for the first group, the widthwise component of a first vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the plurality of first solar cell modules is defined as the first horizontal vector, and for the third group, the widthwise component of a second vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the third number of solar cell modules is defined as the second horizontal vector, wherein the direction of the first horizontal vector and the direction of the second horizontal vector are opposite, and the second horizontal vector extends away from the runway.

10. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aforementioned land includes the first area and the second area, The first region and the second region are located in the width direction of the runway, perpendicular to the longitudinal direction, with the runway or the landing strip in between. The first group is installed in the second region, The plurality of groups includes a fourth group, which is installed in the first region and consists of a fourth number of solar cell modules. A photovoltaic power generation system in which, for the first group, the widthwise component of a first vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the plurality of first solar cell modules is defined as the first horizontal vector, and for the fourth group, the widthwise component of a third vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the fourth number of solar cell modules is defined as the third horizontal vector, the direction of the first horizontal vector and the direction of the third horizontal vector are opposite, and the direction of both the first horizontal vector and the third horizontal vector is away from the runway.

11. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aforementioned land includes the first area and the second area, The first region and the second region are located in the width direction of the runway, perpendicular to the longitudinal direction, with the runway or the landing strip in between. The plurality of groups includes a fifth group installed in the first region and consisting of a fifth number of solar cell modules, and a sixth group installed in the second region and consisting of a sixth number of solar cell modules. A solar power generation system in which, for the fifth group, the widthwise component of the fourth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the fifth number of solar cell modules is defined as the fourth horizontal vector, and for the sixth group, the widthwise component of the fifth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the sixth number of solar cell modules is defined as the fifth horizontal vector, the direction of the fourth horizontal vector and the direction of the fifth horizontal vector are opposite, and the direction of both the fourth horizontal vector and the fifth horizontal vector is away from the runway.

12. The system comprises multiple solar panels installed on land along the longitudinal direction of the runway or landing strip at the airport, The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The estimated irradiance is the estimated irradiance of reflected light incident on a specific location in one or more spaces, such as the cockpit of an aircraft in flight and the control room of an air traffic control tower, in response to the reflection of sunlight by the plurality of solar cell modules. The aforementioned plurality of groups includes a seventh group consisting of a seventh number of solar cell modules, A photovoltaic power generation system in which, for the seventh group, the angle between a sixth vector that virtually extends away from the light-receiving surface along the normal direction of the light-receiving surface of each of the seventh number of solar cell modules and a seventh vector that virtually extends from the light-receiving surface to the specific position in the control room of the control tower is 90 degrees or more.

13. The system comprises multiple solar modules installed on land along the longitudinal direction of the runway or landing strip at the airport, a first substation, and a second substation. The plurality of solar cell modules comprises a plurality of groups, including a first group consisting of a plurality of first solar cell modules, and a second group consisting of two or more solar cell modules, each including one or more second solar cell modules. The light reflectance at the light-receiving surface of each of the one or more second solar cell modules is smaller than the light reflectance at the light-receiving surface of each of the plurality of first solar cell modules. When the sun performs its annual diurnal motion, the estimated irradiance of the reflected light incident on the cockpit of an aircraft in flight or the control room of an air traffic control tower, in accordance with the reflection of sunlight by the multiple solar cell modules, is below a predetermined irradiance. The aforementioned groups are connected to the power company's grid at the same interconnection point via service lines. The first group is connected to the transformer of the first substation equipment, The second group is connected to the transformer of the second substation equipment, The first substation is connected to the interconnection point via the first service drop, The second substation is connected to the interconnection point via a second service drop, and is a solar power generation system.

14. A solar power generation system according to any one of claims 4 to 11 and 13, A photovoltaic power generation system in which the estimated irradiance is the estimated irradiance of reflected light incident on a specific location in one or more spaces, such as the cockpit of an aircraft in flight and the control room of an air traffic control tower, in response to the reflection of sunlight by the plurality of solar cell modules.

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