Solar cell module, photovoltaic power generation system, and curtain wall unit

Abstract

A solar cell module 10 comprises: an outdoor-side glass panel 12; an indoor-side glass panel 14 disposed opposite to the outdoor-side glass panel 12; a plurality of band-shaped bifacial photovoltaic solar cells 16 disposed at predetermined intervals between the outdoor-side glass panel 12 and the indoor-side glass panel 14; and a reflective layer 20 disposed on an indoor-side surface 14a of the indoor-side glass panel 14.

Description

Solar cell module, solar power generation system, and curtain wall unit

[0008] ,

[0007] ,

[0001] The present disclosure relates to a solar cell module, a solar power generation system, and a curtain wall unit including solar cells.

[0002] Conventionally, a laminated glass type solar cell module in which a solar cell layer is provided between a pair of glass panels has been known (see, for example, Patent Document 1).

[0003] Japanese Unexamined Patent Application Publication No. 2017-85750, Japanese Unexamined Patent Application Publication No. 2014-136919, Japanese Unexamined Patent Application Publication No. 2011-163059

[0004] In the solar cell module as described above, it is desirable to improve the power generation efficiency.

[0005] The present disclosure has been made in view of such problems, and an object thereof is to provide a solar cell module capable of improving the power generation efficiency.

[0006] In order to solve the above problems, a solar cell module according to an aspect of the present disclosure includes an outdoor glass panel, an indoor glass panel arranged to face the outdoor glass panel, and a plurality of strip-shaped double-sided light-receiving solar cell cells arranged at a predetermined interval between the outdoor glass panel and the indoor glass panel, and a reflective layer arranged on the indoor side surface of the indoor glass panel.

[0007] It is a schematic cross-sectional view for explaining a solar cell module according to the first embodiment. It is a schematic front view of a curtain wall using a curtain wall unit according to the second embodiment. It is a schematic front view of a curtain wall unit according to the second embodiment. It is an A-A schematic longitudinal cross-sectional view of the curtain wall unit shown in FIG. 3. FIGS. 5(a) and 5(b) are diagrams for explaining the deformation of the curtain wall unit when there is shaking due to an earthquake. It is a schematic front view of a curtain wall unit according to the third embodiment. It is a diagram for explaining the deformation of the curtain wall unit when there is shaking due to an earthquake. It is a schematic view showing a solar power generation system using a solar cell module according to the fourth embodiment.

[0008] The present disclosure will be described below with reference to the drawings, based on preferred embodiments. The following configurations are illustrative for the purpose of understanding the present disclosure, and the scope of the present disclosure is determined solely by the attached claims. Identical or equivalent components and members shown in each drawing are denoted by the same reference numerals, and redundant descriptions are omitted where appropriate. In addition, the dimensions of members in each drawing are shown enlarged or reduced as appropriate for ease of understanding. Furthermore, some members that are not important for describing the embodiments are omitted in each drawing.

[0009] [First Embodiment] Figure 1 is a schematic cross-sectional view illustrating a solar cell module 10 according to the first embodiment. The solar cell module 10 is placed in an opening in a building.

[0010] As shown in Figure 1, the solar cell module 10 comprises an outdoor glass panel 12, an indoor glass panel 14 positioned opposite the outdoor glass panel 12, and a plurality of strip-shaped double-sided light-receiving solar cells 16 positioned between the outdoor glass panel 12 and the indoor glass panel 14. The solar cell module 10 is a laminated glass type solar cell module in which a plurality of strip-shaped double-sided light-receiving solar cells 16 are provided between a pair of light-transmitting glass panels 12 and 14.

[0011] The double-sided photodetector solar cell 16 may be, for example, a stack of two solar cell layers. The double-sided photodetector solar cell 16 used in this first embodiment is a solar cell that is highly sensitive to near-infrared light with wavelengths from 780 nm to 1200 nm (i.e., has high photoelectric conversion efficiency). The double-sided photodetector solar cell 16 may use thin-film silicon, organic thin film, dye-sensitized film, perovskite, etc. The solar cell may be semi-transparent or transparent. Multiple double-sided photodetector solar cells 16 are electrically connected in series to obtain the required predetermined voltage.

[0012] Multiple strip-shaped bifacial photodetector solar cells 16 are arranged at predetermined intervals in the height direction. That is, the multiple bifacial photodetector solar cells 16 are arranged in a horizontal stripe pattern. Each bifacial photodetector solar cell 16 may be arranged to extend horizontally, or to extend in a direction inclined with respect to the horizontal direction. When the bifacial photodetector solar cells 16 are arranged in a horizontal stripe pattern, the amount of power generated depends on the altitude of the sun. The power generated by each bifacial photodetector solar cell 16 is taken out to the outside via a junction box (not shown). In another embodiment, the bifacial photodetector solar cells 16 may be arranged at predetermined intervals in the horizontal direction. That is, the bifacial photodetector solar cells 16 may be arranged in a vertical stripe pattern. When the bifacial photodetector solar cells 16 are arranged in a horizontal stripe pattern, the amount of power generated depends on the azimuth angle of the sun.

[0013] Multiple strip-shaped double-sided photodetector solar cells 16 are covered with a encapsulant 18. That is, the space between two adjacent double-sided photodetector solar cells 16 is filled with the encapsulant 18. The encapsulant 18 may be made of a light-transmitting material. For example, the encapsulant 18 can be made of lightweight and durable ethylene vinyl acetate copolymer resin (EVA), polyvinyl butyral (PVB), ionomer, silicone, etc.

[0014] A pair of protective films (not shown) may be provided so as to sandwich the sealing material 18. The protective films may be made of a light-transmitting material. For example, the protective films can be made of ETFE (Ethylene Tetra Fluoro Ethylen), polycarbonate (PC), polyethylene (PET), etc.

[0015] The solar cell module 10 according to this first embodiment further includes a reflective layer 20 disposed on the indoor side surface 14a of the indoor glass panel 14. The reflective layer 20 may be a LOW-E coating layer having a reflective layer and a low-emission layer (a layer that suppresses radiation to the indoor side). The reflective layer 20 may be provided over substantially the entire area of ​​the indoor side surface 14a of the indoor glass panel 14. The reflective layer 20 may be configured to transmit visible light while reflecting light with wavelengths from near-infrared onwards. Such a reflective layer can be formed, for example, from a dielectric multilayer film.

[0016] When the solar cell module 10 according to this first embodiment is applied to an opening in a building, the exterior glass panel 12 is positioned to face the outside.

[0017] Figure 1 schematically illustrates sunlight incident on a solar cell module 10. Sunlight includes ultraviolet light, visible light, near-infrared light, mid-infrared light, and far-infrared light. In Figure 1, sunlight SL1 (solid line) passes through the outdoor glass panel 12 and is incident on the bifacial solar cell 16. The ultraviolet light, visible light, and near-infrared light contained in sunlight SL1 are converted into electricity by the solar cell on the outdoor side of the bifacial solar cell 16. If the bifacial solar cell 16 is semi-transparent, the visible light contained in sunlight SL1 passes through the bifacial solar cell 16, the indoor glass panel 14, and the reflective layer 20, and is irradiated into the room.

[0018] In Figure 1, sunlight SL2 passes through the outdoor glass panel 12, between the two double-sided photodetector solar cells 16, and further through the indoor glass panel 14 before entering the reflective layer 20. Of the sunlight SL2, visible light VL (dashed line) passes through the reflective layer 20 and irradiates the room. On the other hand, of the sunlight SL2, near-infrared light NIR (dotted line) is reflected by the reflective layer 20 and enters the double-sided photodetector solar cells 16. The near-infrared light NIR is converted into electricity by the indoor-side solar cell of the double-sided photodetector solar cells 16. Thus, according to the solar cell module 10 of this first embodiment, not only near-infrared light that directly enters the double-sided photodetector solar cell 16, but also near-infrared light that passes between the two double-sided photodetector solar cells 16 can be reflected by the reflective layer 20 and returned to the double-sided photodetector solar cells 16, where it can be converted into electricity. This improves power generation efficiency and heat shielding efficiency.

[0019] Furthermore, according to the solar cell module 10 of this first embodiment, visible light VL of the sunlight SL2 that passes between the two double-sided light-receiving solar cells 16 is transmitted through the reflective layer 20 and irradiated into the room, thereby increasing power generation efficiency while also allowing light to enter the room.

[0020] Here, when the distance between the double-sided photodetector solar cell 16 and the reflective layer 20 is d1, and the spacing between the double-sided photodetector solar cells 16 is d2, it is preferable that the distance d1 is less than or equal to the spacing d2 (d1 ≤ d2). In this case, compared to when the distance d1 is greater than the spacing d2 (d1 > d2), more near-infrared light (NIR) can be incident on the indoor side surface of the double-sided photodetector solar cells 16, thereby improving power generation efficiency. When the thickness of the outdoor glass panel 12 is t1 and the thickness of the indoor glass panel 14 is t2, it is preferable that t1 ≥ t2. This is because the amount of power generated tends to be greater than when t1 < t2. However, even when t1 < t2, it is possible to improve power generation efficiency. Also, even when d1 > d2, the relationship may change depending on the glass thickness. Furthermore, it is preferable that the spacing d2 between the double-sided photodetector solar cells 16 is greater than the width w of the double-sided photodetector solar cells 16 (d2 > w). In this case as well, power generation efficiency can be improved. However, in some cases, the amount of power generated can be large even when d² ≤ w.

[0021] [Second Embodiment] Conventionally, curtain walls using glass panels equipped with solar cells are known (see, for example, Patent Document 2).

[0022] In curtain walls like the one described above, it is desirable to be able to easily inspect the solar cells.

[0023] This disclosure is made in view of these challenges, and its purpose is to provide a technology that allows for easy inspection of the power generation performance of a curtain wall unit equipped with solar cells.

[0024] To solve the above problems, a curtain wall unit in one embodiment of the present disclosure comprises a solar cell module in which solar cells are sandwiched between a pair of glass panels; a frame that supports the outer peripheral edges of the glass panels, the frame including a lower horizontal frame member disposed below the glass panels; a junction box for extracting power generated by the solar cells, disposed in the space between the lower horizontal frame member and the lower end of the glass panels; and wiring cables extending from the junction box, disposed in the space.

[0025] Another aspect of the present disclosure is also a curtain wall unit. This curtain wall unit comprises a solar cell module in which solar cells are sandwiched between a pair of glass panels; a frame supporting the outer edges of the glass panels, the frame including vertical frame members positioned to the sides of the glass panels; a junction box for extracting power generated by the solar cells, positioned in the space between the vertical frame members and the side edges of the glass panels; and wiring cables extending from the junction box, positioned in the space.

[0026] Figure 2 is a schematic front view of a curtain wall 1010 using the second curtain wall unit 1012. As shown in Figure 2, the curtain wall 1010 is constructed by arranging multiple curtain wall units 1012 (in this case, six curtain wall units 1012A to 1012F) vertically and horizontally around the outer perimeter of the building.

[0027] The glass panels 1014 of each curtain wall unit 1012 are positioned to face the interior space of the building to which the curtain wall 1010 is installed.

[0028] Multiple solar cells 1016 are arranged in a matrix on the glass panel 1014 of each curtain wall unit 1012. The solar cells 1016 are configured to convert light energy into electricity using the photovoltaic effect. The solar cells 1016 may be, for example, crystalline silicon solar cells. Multiple solar cells 1016 are connected to each other by wiring (not shown).

[0029] The curtain wall units 1012 on the same floor are connected in series by cable 1022 to form a string 1024. In the second embodiment shown in Figure 2, the curtain wall units 1012A, 1012B, and 1012C on the upper floor are connected in series by cable 1022 to form a first string 1024A. Similarly, the curtain wall units 1012D, 1012E, and 1012F on the lower floor are connected in series by cable 1022 to form a second string 1024B. The first string 1024A on the upper floor and the second string 1024B on the lower floor are connected in parallel by cable 1023 and aggregated into a power conditioner (PCS) 1026. The power conditioner 1026 performs processing such as converting DC to AC.

[0030] Thus, in each string 1024, multiple curtain wall units 1012 equipped with solar cells are connected in series, allowing for a high voltage to be obtained. However, due to the series connection, if one curtain wall unit 1012 in a string 1024 fails, the amount of power generated from that string 1024 may decrease. Therefore, it is extremely important to periodically check the power generation performance of each curtain wall unit 1012 in the curtain wall 1010.

[0031] Figure 3 is a schematic front view of the curtain wall unit 1012 according to the second embodiment. Figure 4 is a schematic longitudinal cross-sectional view of the curtain wall unit 1012 shown in Figure 3, taken along line A-A.

[0032] The curtain wall unit 1012 comprises a glass panel 1014, a frame 1030 that supports the outer peripheral end of the glass panel 1014, and a junction box 1032.

[0033] As shown in Figure 4, the glass panel 1014 includes a first glass panel 1014a and a second glass panel 1014b. The first glass panel 1014a and the second glass panel 1014b are rectangular in shape when viewed from the front. A solar cell layer 1034 is sandwiched between the pair of first glass panels 1014a and second glass panel 1014b, and these constitute a solar cell module. When used as a double-glazed panel, another glass panel is placed between this solar cell module and the air layer.

[0034] The solar cell layer 1034 is a layer in which multiple solar cells 1016 are arranged in a matrix. In the solar cell layer 1034, multiple solar cells are electrically connected to obtain the required predetermined voltage. The power generated in the solar cell layer 1034 is taken out to the junction box 1032 via wiring (not shown).

[0035] In the curtain wall unit 1012, the glass panel 1014, which sandwiches the solar cell layer 1034, is supported by a frame 1030. In the case of double-glazed glass, the frame 1030 supports the glass panel 1014 and another glass panel. The frame 1030 has a structure in which an upper horizontal frame member 1030a, a lower horizontal frame member 1030b, a left vertical frame member 1030c, and a right vertical frame member 1030d are assembled in a rectangular shape. The upper horizontal frame member 1030a is positioned above the glass panel 1014, the lower horizontal frame member 1030b is positioned below the glass panel 1014, the left vertical frame member 1030c is positioned to the left of the glass panel 1014, and the right vertical frame member 1030d is positioned to the right of the glass panel 1014. The frame 1030 is made of a metal such as aluminum. Frame 1030 has connecting parts (not shown) formed therein, and the frames 1030 of adjacent curtain wall units 1012 are connected by engaging their connecting parts with each other.

[0036] A groove 1036 is formed inside each frame member into which the outer peripheral end of the glass panel 1014 is inserted. A setting block 1033 for supporting the load of the glass panel 1014 is placed in the groove 1036 of the lower horizontal frame member 1030b. The glass panel 1014 is bonded and sealed to each frame member by sealant 1038 or a gasket provided on its periphery.

[0037] The junction box 1032 extracts the power generated by the solar cells 1016. This junction box 1032 houses the positive and negative terminals that form the end of a circuit in which multiple solar cells 1016 are connected in series. The junction box 1032 is equipped with a bypass diode and the like to send electricity without passing through some of the solar cells 1016 when some of them are not functioning properly. The power generation performance of the curtain wall unit 1012 can be checked by examining the connector portion of the wiring cable coming out of the junction box 1032 with measuring instruments.

[0038] As shown in Figure 3, two setting blocks 1033 are placed at intervals within the groove 1036 of the lower horizontal frame member 1030b, and these two setting blocks 1033 support the load of the glass panel 1014. The two setting blocks 1033 form a space 1039 between the lower horizontal frame member 1030b and the lower end of the glass panel 1014. In the curtain wall unit 1012 according to this second embodiment, a junction box 1032 is placed in this space 1039 between the lower horizontal frame member 1030b and the lower end of the glass panel 1014. To place it in this space 1039, it is desirable to use a junction box 1032 with a rod-shaped box structure. Wiring cables extending from the junction box 1032 can pass through the outside or inside of the setting block 1033.

[0039] A cable (not shown) extends from the junction box 1032 and is routed to the outside of the frame 1030. A connector (not shown) is provided at the end of the cable. By connecting the connectors, the junction boxes 1032 are connected in series between adjacent curtain wall units 1012. By connecting the junction boxes 1032 of curtain wall units 1012 on the same floor in series, the string 1024 described with reference to Figure 2 is formed.

[0040] When inspecting the power generation performance of a single curtain wall unit 1012, first, the connector is disconnected, and the curtain wall unit 1012 to be inspected is separated from the string 1024. Then, the open-circuit voltage of the solar cell 1016 is measured at the connector to check for any abnormalities. In addition, the terminals and diodes at the junction box 1032 are checked for burnout, etc., to check for any abnormalities in the solar cell 1016. For this check, an opening may be provided in part of the frame 1030. If the junction box 1032 itself cannot be visually inspected, first check whether there is an error in the solar cell module itself. The soundness or malfunction of the solar cell module can be confirmed by performing thermal imaging measurements from the outside using a gondola or drone. Of course, the amount of power generated can also be checked from the inside using the connector cable. If no errors are found in the thermal image, and the specified value is not obtained in the power generation measurement, then diode loss is suspected. For example, if the power conditioner 1026 detects that the power generation in one string 1024 is extremely low, the abnormal curtain wall unit 1012 can be identified and replaced by checking and inspecting the open-circuit voltage and output status of the solar cells 1016 in the curtain wall unit 1012 belonging to that string 1024, as well as estimating errors in the associated junction box 1032.

[0041] If the junction box 1032 is located, for example, in the groove 1036 of the upper horizontal frame member 1030a, the junction box 1032 will be located near the ceiling, making it difficult to access the cable connector portion extending from the junction box 1032 from the interior space of the building, and thus making it difficult to inspect the power generation performance of the curtain wall unit. On the other hand, if the junction box 1032 is located in the groove 1036 of the lower horizontal frame member 1030b, as in the curtain wall unit 1012 according to this second embodiment, the junction box 1032 will be located near the floor, making it easier to access the cable connector portion extending from the junction box 1032 from the interior space of the building, and thus making it easier to inspect the power generation performance of the curtain wall unit.

[0042] Figures 5(a) and 5(b) illustrate the deformation of the curtain wall unit 1012 in the event of shaking caused by an earthquake. Figure 5(a) shows the curtain wall unit 1012 when there is no shaking caused by an earthquake. Figure 5(b) shows the curtain wall unit 1012 when shaking caused by an earthquake occurs. In Figures 5(a) and 5(b), the frame 1030 is shown in a simplified manner.

[0043] Figure 5(b) shows the state in which the left vertical frame member 1030c and the right vertical frame member 1030d tilt to the right due to shaking caused by an earthquake, and the frame 1030 deforms into a rhombus shape. At this time, the glass panel 1014 also tilts to the right with the right setting block 1033 as the pivot point. When shaking occurs due to an earthquake in this way, as can be seen from Figure 5(b), the space 1040 between the upper horizontal frame member 1030a and the upper end of the glass panel 1014 narrows. Therefore, if the junction box 1032 is placed in this space 1040, there is a risk that the junction box 1032 or the cables extending from the junction box 1032 may be damaged or that the inter-story displacement following ability may be affected. There is a risk of damage. In addition, there is a risk that the glass panel 1014 may be damaged by contact with the junction box 1032 or cables.

[0044] In the curtain wall unit 1012 according to the second embodiment, the junction box 1032 is disposed in a space 1039 between the lower horizontal frame member 1030b and the lower end of the glass panel 1014. Since this space does not become narrow due to the presence of the setting block 1033, the junction box 1032 and the cable are not damaged, and damage to the glass panel 1014 due to contact with the junction box 1032 or the cable does not occur either.

[0045] [Third Embodiment] FIG. 6 is a schematic front view of a curtain wall unit 1050 according to the third embodiment. The same or corresponding components as those of the curtain wall unit 1012 described above are denoted by the same reference numerals, and redundant descriptions are omitted as appropriate.

[0046] In the curtain wall unit 1050 shown in FIG. 6, the junction box 1032 is disposed in a space 1041 between the right vertical frame member 1030d and the right side end of the glass panel 1014. The junction box 1032 may be disposed in a space 1042 between the left vertical frame member 1030c and the left side end of the glass panel 1014.

[0047] Thus, even when the junction box 1032 is disposed in the space between the vertical frame member and the side end of the glass panel 1014, it is easy to access the cable connector portion extending from the junction box 1032 from the indoor space of the building, so that it becomes easy to inspect the power generation performance of the curtain wall unit 1050.

[0048] FIG. 7 is a diagram for explaining the deformation of the curtain wall unit 1050 when there is shaking due to an earthquake. Similar to FIG. 5(b) described above, due to the shaking of the earthquake, the frame 1030 is deformed into a rhombus, and the state where the glass panel 1014 is inclined to the right side is shown. As can be seen from FIG. 7, even when the frame 1030 is deformed into a rhombus due to the shaking of the earthquake, the inclination of the glass panel 1014 also occurs simultaneously. Therefore, the space 1041 between the right vertical frame member 1030d and the right end of the glass panel 1014 does not become as narrow as the space 1040 between the upper horizontal frame member 1030a and the upper end of the glass panel 1014, and is ensured to a certain extent. Therefore, even in the curtain wall unit 1050, damage to the junction box 1032 and the cables extending from the junction box 1032 can be prevented. Also, damage to the glass panel 1014 due to contact with the junction box 1032 or the cables can be prevented.

[0049] [Fourth Embodiment] Conventionally, a plurality of solar cell modules have been installed on the roof of a building or the like to construct a solar power generation system. In such a solar power generation system, a plurality of solar cell modules are electrically connected by connecting the cables of adjacent solar cell modules to each other with connectors (for example, Patent Document 3).

[0050] However, the work of connecting the cables of adjacent solar cell modules to each other with connectors is complicated, and it is a factor that reduces the installability of the solar cell modules.

[0051] The present disclosure has been made in view of such problems, and an object thereof is to improve the installability of solar cell modules.

[0052] In order to solve the above problems, a solar cell module according to an aspect of the present disclosure is a solar cell module including a plurality of solar cells, and is configured to be wirelessly and electrically connectable to other solar cell modules.

[0053] Another aspect of the present disclosure is a solar power generation system. This solar power generation system includes a plurality of the above-described solar cell modules.

[0054] Figure 8 is a schematic diagram showing a photovoltaic power generation system 2100 using a solar cell module 2010 according to the fourth embodiment. As shown in Figure 8, the photovoltaic power generation system 2100 comprises a plurality (in this case, three) of solar cell modules 2010 and a power conditioner (PCS: Power Conditioning System).

[0055] Each solar cell module 2010 comprises a plurality of solar cells 2014. The solar cells 2014 are configured to utilize the photovoltaic effect to convert light energy into electricity. The solar cells 2014 may be, for example, crystalline silicon solar cells.

[0056] Multiple solar cells 2014 are arranged in a matrix as shown in Figure 8 and connected in series to each other by wiring 2016. The matrix-arranged solar cells 2014 are sealed with a encapsulant such as EVA (ethylene vinyl acetate) (not shown), and further sandwiched between a cover glass 2018 and a back sheet (not shown). The glass is surrounded by a frame (not shown).

[0057] In this fourth embodiment, the solar cell module 2010 is configured to be electrically connected wirelessly to other solar cell modules. In the photovoltaic power generation system 2100 shown in Figure 8, three solar cell modules 2010 are installed side by side in the left-right direction. The solar cell module 2010 includes a power receiving device 2020 that wirelessly receives power from an adjacent first solar cell module 2010, and a power transmitting device 2022 that wirelessly sends power to an adjacent second solar cell module 2010. The power receiving device 2020 is connected to one end of the wiring 2016 and is located at one side end (left end) 2018a of the cover glass 2018. The power transmitting device 2022 is connected to the other end of the wiring 2016 and is located at the other side end (right end) 2018b of the cover glass 2018.

[0058] The power receiving device 2020 includes a power receiving coil and a power receiving control board. The power transmitting device 2022 includes a power transmitting coil and a power transmitting control board. The solar cell module 2010 is arranged such that the power receiving device 2020 faces the power transmitting device 2022 of a first other solar cell module 2010, and the power transmitting device 2022 faces the power receiving device 2020 of a second other solar cell module 2010. Wireless power transmission is performed between the power transmitting device 2022 and the power receiving device 2020 by arranging the power transmitting coil of the power transmitting device 2022 and the power receiving coil of the power receiving device 2020 facing each other. The wireless power transmission method may be an electromagnetic induction method, a magnetic field resonance method, or a microwave wireless method.

[0059] In the solar power generation system 2100, multiple solar cell modules 2010 are wirelessly and electrically connected in series. By connecting multiple solar cell modules 2010 in series, the voltage can be increased. Multiple solar cell modules 2010 connected in series are also called a "solar cell string". At the downstream solar cell module 2010 (the solar cell module 2010 on the far right in Figure 2001), the output terminal of the wiring 2016 is connected to a power conditioner (PCS: Power Conditioning System) 2012 via cable 2024. The power conditioner 2012 performs processing such as converting DC to AC. In Figure 8, one solar cell string is connected to the power conditioner 2012, but multiple solar cell strings may be connected in parallel to the power conditioner 2012 in order to obtain a predetermined power.

[0060] In the solar power generation system 2100 shown in Figure 8, the downstream solar cell module 2010 and the power conditioner 2012 are connected by a cable 2024. However, if the power conditioner 2012 can be placed near the solar cell module 2010, the solar cell module 2010 and the power conditioner 2012 may be electrically connected wirelessly. That is, a power transmission device 2022 may be provided at the output terminal of the wiring 2016 of the downstream solar cell module 2010, and wireless power transmission may be performed between it and a power receiving device 2020 provided on the power conditioner 2012.

[0061] As described above, the solar cell module 2010 according to this fourth embodiment is configured to be electrically connected wirelessly to other solar cell modules. Therefore, when installing the solar power generation system 2100 on the roof of a building or the like, the solar cell modules 2010 can be arranged so that the power receiving device 2020 faces the power transmitting device 2022 of the adjacent solar cell module 2010. This eliminates the need to connect cables extending from the solar cell modules with connectors, as in the past, thus improving installation efficiency. Furthermore, eliminating the need for cables to connect the solar cell modules reduces costs and eliminates the need to consider cable routing, significantly improving installation efficiency.

[0062] In the fourth embodiment described above, the solar cell modules 2010 were installed side by side in the left-right direction, but the direction of installation is not particularly limited, and the solar cell modules 2010 may be installed vertically as shown in Figure 8. Alternatively, multiple solar cell modules 2010 arranged side by side may be placed in two rows, with only the portion connecting the upper and lower rows connected vertically, so that all of the solar cell modules 2010 in both rows are connected in series.

[0063] The solar cell module 2010 according to this fourth embodiment can be applied not only to the roof of a building, but also to the exterior walls of a building, such as curtain walls, and to window glass. Furthermore, the solar cell module 2010 according to this fourth embodiment can be applied not only to buildings, but also to unused land such as vacant lots. The advantage of not using cables to connect the solar cell modules 2010 to each other increases as the number of solar cell modules 2010 to be installed increases.

[0064] A particular aspect of the present disclosure is as follows: (1) A solar cell module comprising: an outdoor glass panel; an indoor glass panel disposed opposite to the outdoor glass panel; a plurality of strip-shaped bifacial solar cells disposed at predetermined intervals between the outdoor glass panel and the indoor glass panel; and a reflective layer disposed on the indoor side surface of the indoor glass panel. (2) The solar cell module according to item 1, wherein the reflective layer is configured to transmit visible light while reflecting near-infrared light. (3) The solar cell module according to item 1 or 2, wherein the distance between the bifacial solar cells and the reflective layer is smaller than the spacing between the plurality of bifacial solar cells. (4) The solar cell module according to any one of items 1 to 3, wherein the spacing between the bifacial solar cells is greater than the width of the bifacial solar cells. (5) A curtain wall unit comprising: a solar cell module with solar cells sandwiched between a pair of glass panels; a frame supporting the outer peripheral ends of the glass panels, the frame including a lower horizontal frame member positioned below the glass panels; a junction box for extracting power generated by the solar cells, positioned in the space between the lower horizontal frame member and the lower end of the glass panels; and wiring cables extending from the junction box, positioned in the space. (6) The curtain wall unit according to item 5, further comprising a setting block positioned on the lower horizontal frame member to support the load of the glass panels. (7) A curtain wall unit comprising: a solar cell module with solar cells sandwiched between a pair of glass panels; a frame supporting the outer peripheral ends of the glass panels, the frame including a vertical frame member positioned to the side of the glass panels; a junction box for extracting power generated by the solar cells, positioned in the space between the vertical frame member and the side end of the glass panels; and wiring cables extending from the junction box, positioned in the space. (8) A solar cell module comprising a plurality of solar cells, configured to be electrically and wirelessly connectable to other solar cell modules.(Clause 9) The solar cell module according to Clause 8, further comprising a power receiving device for wirelessly receiving power from a first other solar cell module, and a power transmitting device for wirelessly transmitting power to a second other solar cell module. (Clause 10) The solar cell module according to Clause 9, wherein the power receiving device includes a power receiving coil, and the power transmitting device includes a power transmitting coil. (Clause 11) A photovoltaic system comprising a plurality of solar cell modules according to any one of Clauses 8 to 10.

[0065] The present invention has been described above based on embodiments. These embodiments are illustrative, and it will be understood by those skilled in the art that various modifications and changes are possible within the scope of the claims of the present invention, and that such modifications and changes are also within the scope of the claims of the present invention. Accordingly, the descriptions and drawings herein should be treated as illustrative rather than limiting.

[0066] This disclosure can be used in solar cell devices.

[0067] 10 Solar cell module, 12 Outdoor glass panel, 14 Indoor glass panel, 16 Double-sided light-receiving solar cell, 18 Encapsulation material, 20 Reflective layer, 1010 Curtain wall, 1012, 1050 Curtain wall unit, 1014 Glass panel, 1016 Solar cell, 1022 Cable, 1024 String, 1026 Power conditioner, 1030 Frame, 1032 Junction box, 1033 Setting block, 1034 Solar cell layer, 1036 Groove, 2010 Solar cell module, 2012 Power conditioner, 2014 Solar cell, 2016 Wiring, 2018 Cover glass, 2020 Power receiving device, 2022 Power transmitting device, 2024 Cable, 2100 Solar power generation system.

Claims

1. A solar cell module comprising: an outdoor glass panel; an indoor glass panel positioned opposite the outdoor glass panel; a plurality of strip-shaped double-sided light-receiving solar cells arranged at predetermined intervals between the outdoor glass panel and the indoor glass panel; and a reflective layer positioned on the indoor side surface of the indoor glass panel.

2. The solar cell module according to claim 1, wherein the reflective layer is configured to transmit visible light while reflecting near-infrared light.

3. The solar cell module according to claim 1 or 2, wherein the distance between the double-sided light-receiving solar cell and the reflective layer is less than or equal to the spacing between the double-sided light-receiving solar cells.

4. The solar cell module according to claim 1 or 2, wherein the spacing between the double-sided photosensitive solar cells is greater than the width of the double-sided photosensitive solar cells.

5. A curtain wall unit comprising: a solar cell module in which solar cells are sandwiched between a pair of glass panels; a frame supporting the outer peripheral ends of the glass panels, the frame including a lower horizontal frame member positioned below the glass panels; a junction box for extracting power generated by the solar cells, positioned in the space between the lower horizontal frame member and the lower end of the glass panels; and wiring cables extending from the junction box, positioned in the space.

6. The curtain wall unit according to claim 5, further comprising a setting block arranged on the lower horizontal frame member to support the load of the glass panel.

7. A curtain wall unit comprising: a solar cell module in which solar cells are sandwiched between a pair of glass panels; a frame supporting the outer peripheral edges of the glass panels, the frame including vertical frame members disposed on the sides of the glass panels; a junction box for extracting power generated by the solar cells, disposed in the space between the vertical frame members and the side edges of the glass panels; and wiring cables extending from the junction box, disposed in the space.

8. A solar cell module comprising multiple solar cells, configured to be electrically and wirelessly connectable with other solar cell modules.

9. The solar cell module according to claim 8, comprising a power receiving device for wirelessly receiving power from a first other solar cell module, and a power transmitting device for wirelessly transmitting power to a second other solar cell module.

10. The solar cell module according to claim 9, wherein the power receiving device includes a power receiving coil, and the power transmitting device includes a power transmitting coil.

11. A photovoltaic power generation system comprising a solar cell module according to any one of claims 8 to 10.

Images