Solar array

Abstract

To provide a solar array in which a plurality of solar cell modules are connected in a partially overlapped state, and in which reduction in output due to shielding of scattered light is suppressed.SOLUTION: In a solar array with a plurality of solar modules installed on an inclined plane, the plurality of solar modules respectively include a plurality of series-connected solar cells; adjacent solar cell modules from among the plurality of solar cell modules are arranged with their principal surfaces facing upward and partially overlapping each other; and at least a part of the end face of the lower end of an upper solar cell module 3 among the adjacent solar cell modules serves as a reflecting portion 300 that reflects light toward the main surface of a lower solar cell module 4 among the adjacent solar cell modules.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a solar cell array that is installed on an inclined surface and that is configured by connecting a plurality of solar cell modules in a partially overlapping state. [Background technology]

[0002] Solar cell arrays with various structures have been proposed in the past. One such solar cell array is a solar energy system that includes multiple rows of modules arranged with gaps between them, and a row of reflectors arranged between adjacent rows of modules (Patent Document 1). Each row of modules is composed of a plurality of PV modules lined up. Each row of reflectors is composed of a plurality of reflectors that reflect light toward the PV modules. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2012-518909 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when this solar cell array is installed on an inclined surface that slopes in the row direction and adjacent PV modules are arranged in a module row so that they partially overlap each other, a step occurs between the upper and lower PV modules among the adjacent PV modules. In such a solar cell array, when cells in a module row are connected in series, the amount of light received by the cell closest to the step in the lower PV module (the cell that is most blocked by scattered light) decreases, and this cell becomes a resistance within the module, which reduces the power generation of the cells other than this cell in the module, and there is a risk that the desired output cannot be secured.

[0005] The present invention aims to provide a solar cell array in which a plurality of solar cell modules are connected in a partially overlapping state, and in which a decrease in output due to the blocking of scattered light is suppressed. [Means for solving the problem]

[0006] The solar cell array of the present invention is a solar cell array installed on an inclined surface and comprising a plurality of solar cell modules, each of the plurality of solar cell modules comprising a plurality of solar cell cells connected in series, adjacent solar cell modules among the plurality of solar cell modules are arranged with their respective principal surfaces facing upward and partially overlapping each other, and at least a portion of the side surface of the lower end of a solar cell module located above the adjacent solar cell modules serves as a reflective portion that reflects light toward the principal surface of the solar cell module located below the adjacent solar cell modules.

[0007] With this configuration, light reflected from the side surface of the lower end of the solar cell module located above is incident on the main surface of the solar cell module located below, thereby compensating for the scattered light blocked by the solar cell module located above, thereby suppressing a decrease in the output of the solar cell array.

[0008] In the solar cell array, the entire side surface of the lower end of the upper solar cell module may be the reflecting portion.

[0009] With this configuration, the entire side surface of the lower end of the upper solar cell module reflects light back to the main surface of the lower solar cell module, thereby further suppressing a decrease in output from the solar cell array.

[0010] In the solar cell array, a reflector of the solar cell module located above may have a higher infrared light reflectance than a visible light reflector of the solar cell module located above.

[0011] With this configuration, the side surface of the lower end of the solar cell module located above reflects visible light while more strongly reflecting infrared light, thereby suppressing light pollution caused around the installation location of the solar cell array while also suppressing a decrease in output.

[0012] Moreover, in the solar cell array, The reflectance of the reflective portion of the solar cell module positioned above may be 10% or more.

[0013] With this configuration, the reflectance of the reflective portion of the solar cell module located above is greater than the reflectance of the end face of a typical solar cell module (e.g., about 4.5%), thereby further suppressing the decrease in output of the solar cell array.

[0014] In addition, in the solar cell array, the larger of the average reflectance of light with a wavelength of 380 nm or more and less than 780 nm at the reflective portion of the solar cell module located above and the average reflectance of light with a wavelength of 780 nm or more and less than 1100 nm at the reflective portion of the solar cell module located above may be 10% or more.

[0015] With this configuration, the reflectance of the reflective portion of the solar cell module located above is greater than the reflectance of the end face of a typical solar cell module (e.g., about 4.5%), thereby further suppressing the decrease in output of the solar cell array.

[0016] In the solar cell array, each of the plurality of solar cells may be in the form of a strip that is long and narrow in a direction along an upper end side surface and a lower end side surface of each of the plurality of solar cell modules.

[0017] According to this configuration, an effective measure can be taken in a solar cell array including solar cells having a shape that is susceptible to the effects of blocking scattered light. Effect of the Invention

[0018] As described above, according to the present invention, it is possible to provide a solar cell array in which a plurality of solar cell modules are connected in a partially overlapping state, and in which a decrease in output due to the blocking of scattered light is suppressed. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a plan view of a solar cell array according to this embodiment. [Diagram 2] FIG. 2 is a side view of the solar cell array. [Diagram 3] FIG. 3 is a perspective view of the solar cell array. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

[0021] The solar cell array 1 is installed on an inclined surface. For example, the solar cell array 1 is installed on the roof of a building such as a private house with its main surface (light receiving surface) facing upward. The solar cell array 1 includes a plurality of solar cell modules 2 as shown in FIG.

[0022] Each of the multiple solar cell modules 2 includes multiple solar cell cells 20 connected in series. Adjacent solar cell modules 2 among the multiple solar cell modules 2 are arranged with their respective main surfaces 21 facing the sunlight incidence direction and partially overlapping each other. Furthermore, as shown in Figures 2 and 3, at least a part of the side surface 30 of the lower end of a solar cell module 3 located at the upper end of the adjacent solar cell modules 2 serves as a reflective portion 300 that reflects light toward a main surface 41 of a solar cell module 4 located below among the adjacent solar cell modules 2.

[0023] According to the above solar cell array 1, light reflected by the side surface 30 at the lower end of the solar cell module 3 located above is incident on the main surface 41 of the solar cell module 4 located below, thereby compensating for the scattered light blocked by the solar cell module 3 located above, thereby suppressing a decrease in the output of the solar cell array 1.

[0024] The output reduction of the solar cell array 1 caused by arranging the solar cell modules 2 in a partially overlapping state is unlikely to occur in the case of direct light, which is abundant on sunny days. This is because, when installing the solar cell modules 2, the positional relationship between the sun and the inclined surface of the roof on which the solar cell array 1 is installed is adjusted (specifically, the solar cell array 1 is installed on a south-facing roof (in the case of the northern hemisphere) so that the sun is located on the front side of the roof most of the daytime), which makes it difficult for the solar cell modules 2 to block the sunlight due to the steps. On the other hand, such an output reduction of the solar cell array 1 is likely to occur in the case of scattered light, which is abundant on cloudy days. This is because scattered light falls uniformly from the sky, so the components falling from the front side of the inclined surface of the roof (the south side in the case of the northern hemisphere) are received without being blocked by the steps, but the components falling from the back side of the inclined surface of the roof (the north side in the case of the northern hemisphere) are blocked by the steps. Unlike the case of direct light, the direction of the scattered light falling is not specific, so it is difficult to improve the output reduction by adjusting the positional relationship between the solar cell modules 2 and the inclined surface of the roof. Incidentally, the proportion of diffuse solar radiation in the total annual solar radiation is approximately 50%. In this solar cell array 1, by forming the reflecting portion 300, some of the approximately 50% can contribute to suppressing the output reduction of the solar cell array 1.

[0025] Although both sides of the solar cell module 2 are sealed with a glass material, for example, the front side may be sealed with a glass material and the back side may be sealed with a resin film.

[0026] In this solar cell array 1, the overlap dimension (overlap dimension in the adjoining direction) of adjacent solar cell modules 2 is, for example, less than 25 mm. Furthermore, the thickness of the solar cell module 2 is, for example, 30 mm or more and 40 mm or less.

[0027] In the solar cell array 1 of this embodiment, the entire side surface 30 at the lower end of the solar cell module 3 located above is the reflective portion 300. As a result, the entire side surface 30 at the lower end of the solar cell module 3 located above reflects light to the main surface 41 of the solar cell module 4 located below, so that a decrease in the output of the solar cell array 1 can be further suppressed. Note that a part of the side surface 30 at the lower end of the solar cell module 3 located above may be the reflective portion 300.

[0028] The reflectance of the infrared light of the reflector 300 of the solar cell module 3 located above is, for example, greater than the reflectance of the visible light of the reflector 300 of the solar cell module 3 located above. In this way, the side surface 30 at the lower end of the solar cell module 3 located above reflects visible light while more reflecting infrared light, thereby suppressing light pollution (for example, glare caused to nearby residents) caused around the installation location of the solar cell array 1 and suppressing a decrease in output.

[0029] Specifically, the reflectance of the reflective portion 300 of the solar cell module 3 located above is 10% or more. More specifically, the larger of the average reflectance of the reflective portion 300 of the solar cell module 3 located above for light with a wavelength of 380 nm or more and less than 780 nm and the average reflectance of the reflective portion 300 of the solar cell module 3 located above for light with a wavelength of 780 nm or more and less than 1100 nm is 10% or more. In this way, since the reflectance of the reflective portion 300 of the solar cell module 3 located above is greater than the reflectance of the end face of a general solar cell module (for example, about 4.5%), the decrease in output of the solar cell array 1 can be further suppressed.

[0030] The reflectance of the reflector 300 on the side surface 30 at the lower end of the solar cell module 3 located above is greater than the reflectance of the side surface 32 at the upper end of the solar cell module 3 located above. Furthermore, the reflector 300 is not formed on the side surface 32 at the upper end of the solar cell module 3 located above. The reflectance of the side surface 32 at the upper end of the solar cell module 3 located above is, for example, approximately 4.5%. The reflector 300 may be formed on the side surface 32 at the upper end of the solar cell module 3 located above.

[0031] In the solar cell array 1 of this embodiment, each of the multiple solar cell 20 is in the form of a long and narrow strip extending in a direction along the upper end side surface 32 and the lower end side surface 30 of each of the multiple solar cell modules 2. In this way, an effective measure can be taken in the solar cell array 1 including the solar cell 20 having a shape that is easily affected by the blocking of scattered light. Of the multiple solar cell 20, the solar cell 20 arranged in the adjoining direction of the solar cell modules 2 are connected in a shingle connection, for example. The shape of the solar cell 20 may be a shape other than a long and narrow strip, for example, a square shape, etc.

[0032] The manufacturing method of the solar cell module 2 used in the above solar cell array 1 (the solar cell array 1 installed on an inclined surface and including a plurality of solar cell modules 2) includes a reflecting portion forming step.

[0033] Each of the plurality of solar cell modules 2 includes a plurality of solar cell cells 20 connected in series, and adjacent solar cell modules 2 among the plurality of solar cell modules 2 are arranged with their respective principal surfaces facing upward and partially overlapping each other. The reflecting portion forming step is a step of forming a reflecting portion 300 that reflects light toward the principal surface 41 of the solar cell module 4 located below among the adjacent solar cell modules 2 by applying, plating, vapor deposition, or immersing a light-reflecting reflective material on at least a part of the side surface 30 of the lower end of the solar cell module 3 located above among the adjacent solar cell modules 2. The reflective material is, for example, a metal such as copper.

[0034] In this manner, by applying, plating, vapor-depositing, or immersing a reflective material onto the side surface 30 of the lower end of the solar cell module 3 located above, a solar cell module 2 for use in a solar cell array 1 with reduced output reduction can be easily formed.

[0035] The solar cell array of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, or part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, part of the configuration of one embodiment can be deleted.

[0036] In the solar cell array 1 of the above embodiment, the reflecting portion 300 on the side surface 30 at the lower end of the solar cell module 3 located at the upper side is formed by applying a reflective material, but it may be formed by attaching a reflective material that reflects light. That is, the reflecting portion forming step may be a step of forming the reflecting portion 300 that reflects light toward the main surface 41 of the solar cell module 4 located below by attaching a reflective material that reflects light to at least a part of the side surface 30 at the lower end of the solar cell module 3 located at the upper side among the adjacent solar cell modules 2. The reflective material is, for example, a metal foil such as copper foil. In this way, by attaching a reflective material that reflects light to the side surface 30 at the lower end of the solar cell module 3 located at the upper side, the solar cell module 2 used in the solar cell array 1 that suppresses the decrease in output can be easily formed even after the solar cell module 2 is assembled. Note that the entire member constituting the frame of the solar cell module 2, including the side surface 30 at the lower end, may be formed of a reflective material with high reflectivity.

[0037] Furthermore, the reflecting portion 300 on the side surface 30 at the lower end of the upper solar cell module 3 may be formed by mechanical processing such as polishing or chemical processing such as etching. [Explanation of symbols]

[0038] Reference Signs List 1: solar cell array, 2: solar cell module, 3: solar cell module located at upper side, 4: solar cell module located at lower side, 20: solar cell cell, 21: main surface, 30: lower end surface, 32: upper end surface, 41: main surface, 300: reflecting portion

Claims

1. A solar cell array installed on an inclined surface and including a plurality of solar cell modules, Each of the plurality of solar cell modules includes a plurality of solar cell cells connected in series; Adjacent solar cell modules among the plurality of solar cell modules are arranged with their respective main surfaces facing upward and partially overlapping each other, at least a part of a side surface of a lower end of an upper one of the adjacent solar cell modules is a reflective portion that reflects light toward a main surface of a lower one of the adjacent solar cell modules, the reflector is located above a main surface of the solar cell module located below, a reflectance of infrared light of a reflective portion of the solar cell module located above is greater than a reflectance of visible light of a reflective portion of the solar cell module located above.

2. 2. The solar cell array according to claim 1, wherein an entire side surface of a lower end of the upper solar cell module is the reflecting portion.

3. 2. The solar cell array according to claim 1, wherein a reflectance of the reflective portion of said upper solar cell module is 10% or more.

4. 4. The solar cell array according to claim 3, wherein the larger of an average reflectance of light having a wavelength of 380 nm or more and less than 780 nm at the reflective portion of the solar cell module located above and an average reflectance of light having a wavelength of 780 nm or more and less than 1100 nm at the reflective portion of the solar cell module located above is 10% or more.

5. 5. The solar cell array according to claim 1, wherein each of the plurality of solar cells is in the form of a strip that is elongated in a direction along the upper end side surface and the lower end side surface of each of the plurality of solar cell modules.