JP2010212280A - Light guide structure for solar cell, solar cell unit and solar cell module - Google Patents

Abstract

A light guide structure for a solar cell capable of efficiently guiding sunlight to the solar cell.
SOLUTION: The light receiving layer 210 into which sunlight is incident, the irregular reflection layer 230 that irregularly reflects the sunlight incident from the light receiving layer 210 as irregularly reflected light, and the light receiving layer 210 and the irregular reflection layer 230 are interposed, It is a light guide structure of a solar cell including a light guide layer 220 that guides irregularly reflected light to the solar cell element. The light receiving layer 210 has a predetermined inclination angle with respect to the light guide layer 220, and a light receiving reflection surface 212 that reflects incident sunlight to the light guide layer 220 side, and sunlight reflected by the light receiving reflection surface 212. Is formed on a boundary surface between the light receiving layer 210 and the light guide layer 220 at a location other than the light entrance and reflects the irregularly reflected light in the light guide layer 220. A reflective surface 216.
[Selection] Figure 1

Description

  The present invention relates to a light guide structure for a solar cell, a solar cell unit including the light guide structure, and a solar cell module in which a plurality of the units are combined. In particular, the present invention relates to a light guide structure capable of efficiently guiding sunlight to a solar cell.

  With increasing interest in global warming and environmental pollution, solar cells that do not emit carbon dioxide or pollutants are being promoted. As a unit of this solar cell, there is one in which a solar cell element is combined with a light guide structure for efficiently guiding sunlight (for example, Patent Document 1).

  This technique relates to a sheet-like concentrator in which a light receiving layer, a light guide layer, an intermediate layer, and an irregular reflection layer are sequentially laminated. The light guide layer made of a high refractive index material is sandwiched between a light receiving layer made of a low refractive index material and an intermediate layer. A part of the surface of the light guide layer has a portion where the light receiving layer is not provided, and the solar cell element is disposed there. On the other hand, a large number of bubbles are included in the irregular reflection layer. The light incident from the light receiving layer is irregularly reflected in various directions by the bubbles in the irregular reflection layer and is incident on the light guide layer. At this time, inside the light guide layer, light that has entered the interface at an incident angle greater than the critical angle is repeatedly reflected in the light guide layer and confined in the light guide layer. And the light in this light guide layer injects into a solar cell element, while repeating the reflection in a light guide layer.

  According to such a concentrator, sunlight irradiated to an area larger than the area of the expensive solar cell element can be guided to the solar cell element, and the energy of sunlight irradiated to the solar cell element It is said that the density can be increased.

International Publication WO2006 / 035698 Fig. 1

  However, even in the above-described conventional technology, it is difficult to say that sufficient light guiding is performed on the solar cell element. This is considered to be due to the large amount of light leaking from the light receiving layer to the outside again before reaching the solar cell element in the sunlight once incident on the light receiving layer. In other words, even if light irregularly reflected by the irregular reflection layer enters the light guide layer, there is a considerable amount of light that enters the interface between the light guide layer and the light receiving layer at an incident angle less than a predetermined critical angle. Almost leaks out of the light receiving layer. For this reason, it is considered that only a part of the sunlight incident on the light receiving layer can be incident on the solar cell element.

  The present invention has been made in view of the above circumstances, and one of its purposes is to provide a light guide structure for a solar cell that can efficiently guide sunlight to the solar cell.

  Moreover, the other objective of this invention is to provide a solar cell unit and a solar cell module provided with the said light guide structure.

  The light guide structure of the solar cell of the present invention is interposed between a light receiving layer on which sunlight is incident, a diffuse reflection layer that irregularly reflects sunlight incident from the light receiving layer as irregularly reflected light, and the light receiving layer and the irregular reflection layer. And a light guide layer that guides the irregularly reflected light to the solar cell element. The light receiving layer includes a light receiving reflection surface, an entrance, and a light guide reflection surface. The light receiving / reflecting surface has a predetermined inclination angle with respect to the light guide layer, and reflects incident sunlight to the light guide layer side. The incident port causes sunlight reflected by the light receiving and reflecting surface to enter the light guide layer. And a light guide reflective surface is formed in locations other than the said entrance at the boundary surface of a light reception layer and a light guide layer, and reflects the irregularly reflected light in a light guide layer.

  According to this configuration, sunlight incident on the light receiving layer can be efficiently guided to the entrance through the light receiving / reflecting surface. In addition, most of the light that is diffusely reflected by the diffuse reflection layer from the entrance through the light guide layer is reflected by the light guide reflection surface and confined in the light guide layer, and only a part of the irregularly reflected light is transmitted from the entrance to the outside. Do not leak into. Therefore, most of the light incident on the light receiving layer can be guided to the solar cell element.

  As an embodiment of the present invention, it is possible to provide a bottom reflection surface on the surface of the irregular reflection layer opposite to the light receiving layer.

  According to this structure, it can suppress that light leaks from the surface on the opposite side to the light reception layer in a light guide structure.

  As an embodiment of the present invention, a side reflection surface is provided on the side surface of the light guide layer.

  According to this structure, it can suppress that light leaks from the side surface in a light guide structure.

  As embodiment of this invention, providing the attachment surface of a solar cell element in the surface at the side of the irregular reflection layer in a light guide layer is mentioned.

  According to this configuration, the light receiving layer and the solar cell element can be overlapped. Thereby, compared with the case where a light reception layer and a solar cell element are paralleled, the whole area of the module which combined the solar cell element with the light guide structure can be made small, enlarging the area of a light reception layer.

  As embodiment of this invention, it is mentioned that the said attachment surface is provided in the center part of the longitudinal direction of a light guide layer.

  According to this configuration, the propagation length in the light guide layer until the light incident on the light receiving layer reaches the solar cell element, as compared with the case where the mounting surface is displaced from the longitudinal center of the light guide layer, and Since the number of reflections can be reduced, light loss can be reduced and light guide efficiency can be increased.

  On the other hand, the solar cell unit of the present invention includes the light guide structure of the solar cell of the present invention and a solar cell element fixed to the mounting surface.

  According to this configuration, sunlight can be efficiently guided to the solar cell element by the light guide structure of the present invention.

  Furthermore, the solar cell module of the present invention relates to a solar cell module in which a plurality of solar cell units are arranged in parallel. This solar cell unit includes the solar cell light guide structure of the present invention and a solar cell element fixed to the mounting surface. And each solar cell unit is arranged in parallel so that the position of the solar cell element of adjacent solar cell units may shift | deviate.

  The photoelectric conversion efficiency of a solar cell element generally decreases as the temperature of the element increases. When sunlight is concentrated on the solar cell elements, the temperature rises. Therefore, when a plurality of solar cell units are arranged in parallel, if the solar cell elements of each unit are adjacent to each other, the temperature rise of each element is further promoted and There is a possibility that the conversion efficiency is lowered. Therefore, if the units are arranged in parallel so that the positions of the solar cell elements of the adjacent units are shifted, heat radiation from the individual solar cell elements is effectively performed, and a decrease in photoelectric conversion efficiency can be suppressed.

  As an embodiment of this solar cell module, a plurality of solar cell units including solar cell elements at the same position shifted from the central portion in the width direction of the light guide layer are used. And it is mentioned that the position of the solar cell element of adjacent solar cell units shifts | deviates by changing direction of an adjacent solar cell unit alternately, and paralleling.

  According to this structure, the solar cell module of the structure which the position of the solar cell element of adjacent solar cell units shift | deviates can be implement | achieved by one type of unit with the common attachment position of a solar cell element.

  According to the light guide structure of the solar cell of the present invention, sunlight can be efficiently guided to the solar cell. Moreover, according to the solar cell unit or solar cell module of the present invention, sunlight irradiated to an area larger than the light receiving area of the solar cell element can be guided to the solar cell element to efficiently generate power.

It is a schematic block diagram which shows the light guide structure which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the manufacturing process of the light guide structure of FIG. It is a schematic block diagram which shows the light guide structure which concerns on Embodiment 2 of this invention. It is a schematic block diagram which shows the light guide structure which concerns on Embodiment 3 of this invention. It is a schematic block diagram which shows the light guide structure which concerns on Embodiment 4 of this invention. It is a schematic block diagram which shows the light guide structure which concerns on Embodiment 5 of this invention. It is a top view of the module which arranged the unit of FIG. 6 in parallel. It is a top view of the module which concerns on Embodiment 6 of this invention. FIG. 10 is a plan view of a module according to Embodiment 7 of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, each of the second and subsequent embodiments will be described with a focus on the differences from the first embodiment, and the other configurations are the same as those of the first embodiment, so that the description thereof will be omitted. Moreover, in each figure, the same code | symbol is attached | subjected to the common member.
(Embodiment 1)

[Configuration of solar cell unit]
<Overall configuration>
As shown in FIG. 1, this solar cell unit is a long and thin sheet-shaped unit including a solar cell element 100 and a light guide structure 200 for guiding sunlight to the element 100. Among them, the light guide structure is 200, the light receiving layer 210, the light guide layer 220, and the irregular reflection layer 230 are sequentially stacked from the sunlight incident side, and further, if necessary, between the irregular reflection layer 230 and the light guide layer 220. An intermediate layer (not shown) may be provided therebetween. Sunlight incident on the light receiving layer 210 is diffusely reflected by the irregular reflection layer 230 through the light guide layer 220. Most of the irregularly reflected light is confined in the light guide layer 220 and repeatedly reflected, and is incident on the solar cell element 100 for photoelectric conversion. Hereafter, each structure of the unit of this example is demonstrated in detail.

<Solar cell element>
The solar cell element 100 may be anything that can convert sunlight into electric energy, and various known elements can be used. For example, there are silicon-based, compound-based, and organic-based solar cells. Silicon-based solar cells include single crystal or polycrystalline crystalline silicon solar cells, and thin-film silicon solar cells in which amorphous silicon is formed into a thin film. Compound solar cells include CIS solar cells made from copper, indium, selenium, etc., GaAs solar cells using compound semiconductors such as gallium arsenide, Cu ₂ ZnSnS ₄ (CZTS) solar cells, There are CdTe-CdS solar cells. In particular, a GaAs solar cell is preferable because it has a high rate of increase in photoelectric conversion efficiency with respect to an increase in light energy incident on the device. Furthermore, organic solar cells include dye-sensitized solar cells.

  Usually, as the form of the element 100, a plate or thin film is preferably used. In the unit of this example, a partial region on one end side of the upper surface of the light guide layer 220 is used as the mounting surface 218 of the solar cell element 100, and the rectangular film-shaped solar cell element 100 is disposed adjacent to the light receiving layer 210. It has become. Light that has been repeatedly reflected in the light guide layer 220 is incident on the solar cell element 100 via the mounting surface 218.

<Light guide structure>
(Light receiving layer)
The light receiving layer 210 is a layer for efficiently allowing sunlight to enter the light guide layer 220 side, and includes a light receiving reflection surface 212, an entrance port 214, and a light guide reflection surface 216. Furthermore, an antifouling coating (not shown) may be applied to the surfaces of the light receiving / reflecting surface 212 and the incident port 214 as necessary.

<Receiving / reflecting surface>
The light receiving / reflecting surface 212 is a reflecting surface for reflecting sunlight and guiding it to the light guide layer 220 side. The light-receiving / reflecting surface 212 has a predetermined inclination angle with respect to the light guide layer 220, and is formed at an angle that allows sunlight in a wide range as much as possible to be incident with respect to an assumed incident angle of sunlight. The reflected sunlight is totally reflected and guided to the light guide layer 220 side. For example, the inclination angle of the light receiving / reflecting surface 212 with respect to the light guide layer 220 is preferably 60 to 90 °. In addition, the light receiving / reflecting surface 212 may be formed by arranging substances having different refractive indexes inside and outside the boundary with the reflecting surface 212 as a boundary, but a coating having a high reflectance, particularly a total reflectance of 99% or more. A reflective coating is preferably applied.

  In this example, a plurality of grooves having an inverted trapezoidal cross section whose bottom is narrower than the top is formed in the light receiving layer 210, and the light receiving / reflecting surface 212 is formed on the side of the groove. By arranging a plurality of pairs of the light-receiving / reflecting surfaces 212 having the V-shaped arrangement, sunlight is reflected by one light-receiving / reflecting surface 212 in the groove and directly incident on the light guide layer 220, or is opposed in the groove. The light can be incident on the light guide layer 220 through reflection between the light receiving and reflecting surfaces 212. Thereby, sunlight incident on the light receiving layer 210 can be efficiently guided to the light guide layer 220.

<Inlet>
The incident port 214 is a window for allowing the light reflected by the light receiving / reflecting surface 212 to enter the light guide layer 220. The portion corresponding to the bottom of the inverted trapezoidal groove described above is not coated with the high reflectance coating formed on the light receiving / reflecting surface 212. Therefore, the sunlight reflected by the light receiving / reflecting surface 212 or the sunlight directly incident on the incident port 214 is incident on the light guide layer 220 through the incident port 214.

  If the ratio of the area of the entrance 214 to the total area of the light receiving layer 210 is small, the ratio of light that has entered the light guide layer 220 once leaked to the outside can be reduced. However, if the ratio is too small, the light enters the light guide layer 220. Since the amount of light that can be produced is reduced, about 10 to 50% is preferable.

《Light guide reflective surface》
On the other hand, the light guide reflection surface 216 reflects the light that enters the light guide layer 220 from the entrance 214 to the light receiving layer 210 side, and reflects the light toward the inside of the light guide layer 220 as much as possible in the light guide layer 220. It is a reflection surface for confining in. The light guide reflection surface 216 is formed in a region where the entrance 214 is not provided on the boundary surface between the light receiving layer 210 and the light guide layer 220. The light guide reflection surface 216 preferably uses the same coating as the light reception reflection surface 212.

(Light guide layer)
The light guide layer 220 is a layer for confining the light guided from the light receiving layer 210 as much as possible inside and guiding the light to the solar cell element 100. The sunlight that has entered the light guide layer 220 from the entrance 214 once reaches the irregular reflection layer 230 described below and is irregularly reflected. Most of the irregularly reflected light is totally reflected by the light guide reflection surface 216 and travels again to the irregular reflection layer 230 side. Therefore, most of the light that has entered the light guide layer 220 from the incident port 214 is incident on the solar cell element 100 from the mounting surface 218 while being repeatedly reflected between the light guide reflection surface 216 and the irregular reflection layer 230. It will be. On the other hand, of the irregularly reflected light, part of the light directed toward the entrance 214 is leaked to the outside, but since the amount of leaked light is very small, a high light collection rate can be achieved.

  In addition, it is preferable to provide an inclined reflection surface 219 in a portion of the light guide layer 220 that faces the attachment surface 218 to which the solar cell element 100 is attached, as necessary. By providing the inclined reflection surface 219, the light in the light guide layer 220 is reflected toward the mounting surface 218, so that the light can be efficiently collected.

(Diffuse reflection layer)
The irregular reflection layer 230 has a function of reducing the amount of light leaking from the incident port 214 by irregularly reflecting the light transmitted through the light guide layer 220 and causing the light to travel in various directions. It is preferable that the irregular reflection layer 230 has a fine uneven surface at the boundary surface with the light guide layer 220 so that light can be irregularly reflected. The irregularities are formed by blasting the boundary surface of the irregular reflection layer 230, forming irregularities with a roller on the irregular reflection layer 230 formed into a flat shape, and further forming a roughened surface from the beginning by molding. realizable. In addition, as shown in Patent Document 1, a layer containing bubbles may be used as the irregular reflection layer 230.

(Middle layer)
Further, if necessary, an intermediate layer is interposed between the light guide layer 220 and the irregular reflection layer 230, and at the boundary surface between the light guide layer 220 and the intermediate layer, the light in the light guide layer 220 is predetermined. The light that enters the boundary surface at an incident angle that is greater than the critical angle may be totally reflected. That is, the light irregularly reflected by the irregular reflection layer 230 passes through the intermediate layer and enters the light guide layer 220, and most of the incident light is confined in the light guide layer 220. When the intermediate layer is provided, the refractive indexes of the light guide layer 220 and the intermediate layer are set to “intermediate layer <light guide layer”.

[Method for manufacturing solar cell unit]
For example, the unit may be manufactured as shown in FIG. In the following manufacturing process, the light receiving layer, the light guide layer, the irregular reflection layer, and the intermediate layer can be composed of various resins and glass. Specific examples of the resin include a fully fluorinated polymer, polymethyl methacrylate, polycarbonate, polystyrene, acrylic, polyamide, polyester, a copolymer based on these, and a mixture thereof. As glass, quartz glass can be suitably used.

  First, as shown in FIG. 2 (a), a base 211 having a plurality of isosceles triangular ridges arranged in parallel at a predetermined interval is formed by a known forming method. In the base 211, an inverted trapezoidal groove is formed between the protrusions.

  Next, total reflection coating is performed on the surface of the ridge, that is, on the upper surface of the base 211, except for the bottom surface of the groove by a known film forming method. This total reflection coating serves as the light receiving reflection surface 212 (FIG. 2B).

  Next, a total reflection coating is applied to a portion corresponding to the back surface of the protrusion on the upper surface of the base portion 211. This total reflection coating becomes the light guide reflection surface 216 (FIG. 2C). That is, on the upper and lower surfaces of the base portion, the front and back of the portion corresponding to the bottom surface of the groove is not subjected to total reflection coating, and the uncoated portion serves as the entrance port 214.

  Then, the base 211 having the above-described coating is adhered to the light guide layer 220 and the irregular reflection layer 230 prepared in advance. In this example, the groove portion of the light receiving layer is hollow, but the groove portion may be filled with a filler that does not affect the optical performance of the light guide structure.

  The light guide layer 220 and the irregular reflection layer 230 can be produced by co-extrusion of a resin, as disclosed in Patent Document 1.

[Operational effect of solar cell unit]
According to the solar cell unit of the present invention, light can be efficiently guided to the light guide layer 220 by the light receiving reflection surface 212 of the light receiving layer 210. In addition, the light that has once entered the light guide layer 220 from the incident port 214 is diffusely reflected by the irregular reflection layer 230, and due to the presence of the light guide reflection surface 216, only a part of the light leaks out from the incident port 214. Therefore, the ratio of light that can be confined in the light guide layer 220 can be increased, and sunlight incident on a larger area than the area of the solar cell element 100 can be efficiently condensed on the solar cell element 100. Can do.

Further, since this solar cell unit is configured to guide light to the solar cell element 100 by the light guide mechanism, a lens for condensing light and a sun tracking mechanism are not required.
(Embodiment 2)

  In addition to the configuration of the first embodiment, as shown in FIG. 3, it is preferable to form a bottom reflection surface 240 by applying a total reflection coating to the bottom surface of the irregular reflection layer 230 (on the side opposite to the light receiving layer 210).

By this bottom reflection surface 240, leakage of light from the irregular reflection layer 230 to the side opposite to the light guide layer 220 can be suppressed, and light can be more efficiently collected on the solar cell element 100.
(Embodiment 3)

  In addition to the configuration of the first embodiment, as shown in FIG. 4, it is preferable to form a side reflection surface 250 by applying a total reflection coating also to the side surface of the light guide layer 220. The side reflection surface 250 is preferably formed so as to extend to the side surface of the irregular reflection layer 230 and, when there is an intermediate layer, the side surface of the intermediate layer.

By forming the side reflection surface 250, light leakage from the side surface of the light guide layer 220 (the diffuse reflection layer 230 or the intermediate layer) is suppressed, and light can be more efficiently collected on the solar cell element 100. Can do. Of course, it is more preferable to provide both the bottom reflection surface 240 and the side reflection surface 250.
(Embodiment 4)

  In Embodiment 1, the solar cell element 100 is provided adjacent to the light receiving layer 210 on the upper surface of the light guide layer 220. However, as illustrated in FIG. 5, the solar cell element 100 is adjacent to the irregular reflection layer 230 on the lower surface of the light guide layer 220. The solar cell element 100 may be provided.

According to this configuration, a part of the solar cell element 100 and the light receiving layer 210 can be overlapped. Therefore, the light incident from the light receiving layer 210 not only reaches the solar cell element 100 through reflection at the light guide layer 220 but also passes through the light guide layer 220 and reaches the solar cell element without reflection. be able to. Therefore, compared with Embodiment 1, the photoelectric conversion efficiency converted per unit area of the unit can be improved. As a result, when a solar cell power generation system or the like is configured by combining a plurality of these units, the installation area of all the units can be reduced.
(Embodiment 5)

  In the first to fourth embodiments, the solar cell element 100 is arranged on one end side in the width direction of the unit (the width direction of the light guide layer 220). However, as shown in FIG. May be arranged.

  According to this configuration, the light propagation length and the number of reflections until the light incident on the light guide layer 220 reaches the solar cell element 100 can be reduced as compared with the unit of Embodiment 1, and the light loss is reduced. Can be reduced. As a result, the light collection rate on the solar cell element 100 can be increased.

When a module is configured by paralleling a plurality of units of the present embodiment, the module is as shown in FIG. That is, the solar cell elements 100 of adjacent units are arranged adjacent to each other.
(Embodiment 6)

  In the first embodiment and the fifth embodiment, the unit in which the arrangement position of the solar cell element 100 in the width direction of each unit is made constant, but a plurality of types of units having different arrangement positions of the solar cell element 100 are prepared. As shown, the positions of the solar cell elements 100 may be different between adjacent units.

In the module of FIG. 7, the solar cell elements 100 of adjacent units are adjacent to each other. In general, as the temperature of the solar cell element 100 increases, the generated voltage decreases. Therefore, as shown in FIG. 7, if the solar cell elements 100 of adjacent units are adjacent to each other, the temperature rise of each element may be promoted, and the power generation efficiency may be reduced. If a plurality of types of units having different positions of the solar cell elements 100 are used as in this example of FIG. 8, the solar cell elements 100 of the adjacent units can be shifted so as not to be adjacent, and the reduction in the power generation efficiency is suppressed. can do.
(Embodiment 7)

  In the sixth embodiment, a plurality of types of units having different arrangement positions of the solar cell elements 100 are used. However, as shown in FIG. 9, similar effects can be realized with one type of unit.

  That is, each solar cell unit is provided with the solar cell element 100 at the same position shifted from the central portion in the width direction of the light guide layer 220. In this example, the solar cell element 100 is provided at about 1/4 of the unit longitudinal direction from one end of the unit.

  When many such one type of units are prepared and a module is configured, the solar cell elements 100 of each unit can be prevented from adjoining by alternately reversing the directions of adjacent units. .

  The scope of the present invention is not limited to the above-described embodiments, and various modifications can be made.

  The light guide structure of a solar cell, the solar cell unit, and the solar cell module of the present invention can be suitably used for a power generation system using sunlight.

100 solar cell elements
200 Light guide structure
210 Light-receiving layer
211 Base 212 Light receiving / reflecting surface 214 Entrance 216 Light guiding / reflecting surface
218 Mounting surface 219 Inclined reflecting surface
220 Light guide layer
230 Diffuse reflection layer
240 Bottom reflective surface
250 Side reflective surface

Claims (8)

A light receiving layer on which sunlight is incident, a diffuse reflection layer that irregularly reflects the sunlight incident from the light receiving layer as irregularly reflected light, and interposed between the light receiving layer and the irregularly reflective layer, guide the irregularly reflected light to the solar cell element. A light guide structure of a solar cell including a light guide layer that emits light,
The light receiving layer is
A light receiving reflection surface having a predetermined inclination angle with respect to the light guide layer, and reflecting incident sunlight to the light guide layer side;
An entrance through which the sunlight reflected by the light receiving reflection surface enters the light guide layer;
A light guide for a solar cell, comprising: a light guide reflection surface which is formed at a boundary surface between the light receiving layer and the light guide layer and other than the entrance and reflects the irregularly reflected light in the light guide layer. Construction.   The light guide structure for a solar cell according to claim 1, further comprising a bottom reflection surface on a surface of the irregular reflection layer opposite to the light receiving layer.   The light guide structure for a solar cell according to claim 1, further comprising a side reflection surface on a side surface of the light guide layer.   The light guide structure for a solar cell according to any one of claims 1 to 3, further comprising a solar cell element mounting surface on a surface of the light guide layer on the irregular reflection layer side.   The light guide structure for a solar cell according to claim 4, wherein the attachment surface is provided at a central portion in a longitudinal direction of the light guide layer. The solar cell light guide structure according to claim 4 or 5,
A solar cell unit comprising a solar cell element fixed to the mounting surface. A solar cell module in which a plurality of solar cell units are arranged in parallel,
The solar cell unit is
The light guide structure of the solar cell according to claim 4,
A solar cell element fixed to the mounting surface,
Each solar cell unit is arranged in parallel so that the position of the solar cell element of adjacent solar cell units may shift. Each solar cell unit includes a solar cell element at the same position shifted from the central portion in the width direction of the light guide layer,
The solar cell module according to claim 7, wherein the positions of the solar cell elements of adjacent solar cell units are shifted by alternately changing the directions of adjacent solar cell units in parallel.

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