JP2016063673A - Protection structure for solar cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protection structure capable of improving total power generation amount and designability of a solar cell, suppressing power generation amount from decreasing due to an obstacle or the like, protecting the solar cell from scattering matter, and preventing generation of light pollution by reflectance.SOLUTION: The protection structure, having a three-dimensional structure installed on the incident light side of the solar cell, includes a physical protection function against the solar cell and a function for changing an incidence angle of incident light as well as a function for changing a reflection angle of light reflected on a surface of the solar cell.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a protective structure having an optical function that is installed on the surface side of a solar cell module.

  In recent years, solar power generation has been spreading from the viewpoint of environmental protection and safety, and has been rapidly spreading to home use. The main type of solar cell is a silicon type solar cell based on a silicon material. However, a solar cell using a compound semiconductor or an organic material has also been made and has different characteristics. In general, there are many cases in which the selection is simply based on a balance between conversion efficiency and price.

  When installing solar cells in ordinary households, design is an important factor in addition to economic efficiency. In a newly built house, it is possible to install solar cells in a form that matches the roof design to some extent, but it is quite difficult to retrofit.

  As for the amount of power generated by solar cells, it cannot always be installed optimally due to the shape of the roof, etc., and there are cases where the shade is caused by obstacles such as neighboring houses and utility poles, resulting in extremely low power generation. is there.

  In particular, when solar cells are simply connected in series, the current value generated by light is dragged to the lowest cell connected in series. In general, the amount of light in the shadow area is about one-tenth that of direct light. Therefore, when 200 cells are connected in series to obtain a general 100V output, only one of these cells appears in the shadow. It just happens that the overall output is reduced to 1/10.

  In addition, the surface of the solar cell is often a glass material, and the surface is flat so that sunlight is reflected in a specific direction. When the incident angle is increased, the reflected light intensity is remarkably increased, and not only can it be used for power generation of solar cells, but also causes problems for neighboring houses.

  Among these problems, with respect to designability and reflected light suppression, a proposal has been made to suppress the designability and reflected light by disposing a ceramic convex bulge and a surface coloring layer (see Patent Document 1).

  In addition, in order to improve the utilization efficiency of sunlight, a proposal for increasing the power generation efficiency in the morning and evening by changing the incident angle of light (see Patent Document 2), and light incident at a wide range of angles using a microlens, etc. The proposal which condenses (refer patent document 3) is made | formed.

JP 2012-134546 A JP-A-8-162658 JP 2009-139418 A

  However, since the solar cell of Patent Document 1 uses scattering on the surface of the solar cell, there is no effect on the reduction in the amount of power generation due to the influence of the obstacle. It also has no power for physical protection due to collision of flying objects.

  In addition, the solar cell of Patent Document 2 is premised on that the solar cell can be installed in the south-central direction, and has no effect at all on the reduction in the amount of power generation due to the influence of the obstacle. In addition, the design is greatly limited, and the design as a building is extremely low.

  Even the light collecting device of Patent Document 3 has no effect on the reduction in the amount of power generation due to the influence of an obstacle, and there is almost no variation in design, and the design as a building is extremely low.

  The present invention has been made in view of these above-mentioned problems, improves design without reducing the amount of power generated by the solar cell, protects the solar cell from scattered objects, and prevents light damage caused by reflected light. It is an object to provide a protective structure that can be used.

  In order to solve the above problems, the present invention is a protective structure having a three-dimensional structure installed on the incident light side of a solar cell, having a physical protection function for the solar cell, and receiving incident light. A protective structure having a function of changing an angle and a function of changing a reflection angle of light reflected on the surface of a solar cell is provided.

  If the protective structure has such a three-dimensional structure, optical design is possible in accordance with the situation of each individual solar cell. Therefore, when the shadow of an obstacle occurs, the part is refracted from the structure. -Light can be supplied using reflection or the like, and since the reflected light does not directly go outside, light pollution can be prevented.

  Furthermore, when the state of an obstacle or the like changes due to a change in the surrounding environment, the amount of power generation can be recovered by changing only the protective structure to an optimum one again.

  In order to have an optical function, it is desirable that these protective structures are made of at least one material selected from a plastic material, a metal material, and an oxide material.

  Further, when the design is particularly important, the protective structure preferably contains a dye or a pigment.

  Further, when determining the material and shape of the protective structure, it is desirable to design using optical calculation.

  The present invention is a protective structure having a three-dimensional structure that is installed on the incident light side of a solar cell, has a physical protection function for the solar cell, and has a function of changing the incident angle of incident light. And has a function of changing the reflection angle of light reflected from the surface of the solar cell.

  For this reason, when the shadow of an obstacle arises, light can be supplied to the portion using refraction / reflection from the structure. Further, since the reflected light does not go directly to the outside, it also prevents light pollution.

  Further, if the protective structure has an optical function, various materials can be used and coloring is possible, so that the design is remarkably improved.

  Since the physical protection function can supplement the strength of the solar cell itself, the physical strength of the solar cell can be reduced correspondingly, and the weight of the solar cell is also effective.

It is a schematic cross section of the protective structure of the present invention. It is a schematic cross section of the protective structure of the present invention. It is a schematic cross section of the protective structure of the present invention. It is a schematic diagram which shows the Example of the protection structure of this invention. It is a schematic diagram of the protection structure of the present invention. It is a schematic diagram of the protection structure of the present invention. It is a schematic diagram of the protection structure of the present invention. It is a schematic diagram of the protection structure of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited thereto.

  Conventionally, there has been no idea of installing a member on the incident light side of the solar cell other than the concentrating solar cell. This is natural in order not to reduce the power generation efficiency of the solar cell. For this reason, only the conversion efficiency in a special evaluation environment is emphasized, and this conversion efficiency walks alone, so that the actual power generation amount at the actual site is not sufficiently recognized. In addition, in the case of residential use, although design is very important, there has been a case where it has not been sufficiently considered so far.

  As a result of careful examination in view of the above points, even if the power generation amount is increased in the actual installation environment or the total power generation amount is slightly decreased, the design is remarkably improved and there is a commercially sufficient advantage. It came to invention of a protection structure.

  FIG. 1 is a schematic cross-sectional view showing an example of a protective structure according to the present invention. The protective structure constituting member 2a has a metal reflecting surface. Further, FIG. 1 shows a state in which incident light (solid arrow) reaches the solar cell module 1.

  As can be easily understood from FIG. 1, incident light is classified into one that is directly incident on the solar cell module 1 and one that is incident on the protective structure constituting member 2 a after being reflected once. Depending on the design method of the protective structural member 2a, the incident light intensity at a specific incident angle can be increased, or the amount of incident light on a specific solar cell can be increased.

  FIG. 2 shows a state in which reflected light (broken line arrow) goes out from the solar cell module 1 in the protection structure according to the present invention of FIG. It can be seen that there are those that go out without changing the angle directly and those that go out in different directions after being reflected by the protective structural member 2a.

  The protective structural member 2a in FIGS. 1 and 2 is drawn so as to be substantially parallel on the facing surface of the solar cell module 1, but in reality, a slight difference in angle is applied to make the light Can be reflected separately. Thereby, it is possible to prevent light pollution caused by reflection of all light in one direction.

  FIG. 3 shows a case where the protective structure constituting member 2b is used in combination with a translucent plastic material and the protective structure constituting member 2a. The angle is changed by refracting the incident light (solid line arrow) and the reflected light (broken line arrow) in the protective structure constituting member 2b.

  The protective structure is not limited to a specific shape because it is intended to protect the solar cell, change the optical path of light, and improve the design. For example, a bar-shaped protective structure constituting member 2c may be used as shown in FIG. 5, or a three-dimensional mesh-like protective structure constituting member 2d may be used as shown in FIG. Moreover, it does not necessarily need to be linear, and a curved protective structure constituting member 2d may be used as shown in FIG. 7, or a conical protective structure constituting member 2e is used as shown in FIG. May be. And these do not need to be homogeneously arranged.

  Moreover, it is not necessary to combine the same kind of constituent members for the production of these protective structures, and constituent members having various shapes may be combined as necessary.

  Furthermore, it is not necessary for all of the protective structures of the present invention to have an optical function, and it is sufficient that only a specific part that is required has an optical function. The other parts mainly take into consideration the design, and for example, simply scatter light. If the installation is such that the sunlight hits uniformly, the optical design should be focused on the design by making the light intensity uniform by scattering the refracted light and reflected light.

  Next, examples of the present invention will be described.

Example 1
First, aluminum was deposited on a PET (polyethylene terephthalate) film having a thickness of 125 microns by sputtering. At this time, the film thickness of aluminum was 140 nm, and a reflectance of 90% or more was obtained.

  After that, the PET film with aluminum was cut into a width of 2 mm and placed on the solar cell module 1 in the arrangement as shown in FIG. The installation interval of the aluminum-attached PET film at this time was 3 mm.

  Then, the solar cell module 1 was irradiated with white light using a solar simulator at an angle of 30 degrees, and the power generation amount with and without the protective structure was compared.

  As a result, a power generation amount of 1.22 times was obtained when the protective structure according to the present invention was installed, compared to the case without the installation.

  Moreover, the reflected light from the solar cell module 1 could be remarkably reduced.

(Example 2)
FIG. 4 shows an example in which the reduction in power generation due to the influence of the shade 4 of the obstacle 3 is improved using this protective structure. Since the shade 4 of the obstacle 3 always extends from the obstacle 3 with the sun behind, the protective structure constituting member 2a having a reflecting function may be installed facing the obstacle 3.

  For example, if shade is generated in 5% of the whole, the amount of light of 5% may be turned to the shaded portion from the remaining 95% region. Although the amount of power generation is lower than when the entire surface is exposed to sunlight, it is possible to prevent a significant decrease in the amount of power generation due to partial shade.

The present invention is effective not only for residential solar cells but also for application to mega solar from the viewpoint of protecting the landscape.

1 solar cell module,
2a, 2b, 2c, 2d, 2e, 2f Protective structure constituent member 3 Obstacle, 4 shade

Claims (4)

  A protective structure having a three-dimensional structure installed on the incident light side of the solar cell, having a physical protection function for the solar cell, and having a function of changing the incident angle of the incident light to the solar cell. And the protective structure characterized by having the function to change the reflection angle of the light reflected by the solar cell surface.   The protective structure according to claim 1, wherein the protective structure is made of at least one material selected from a plastic material, a metal material, and an oxide material.   The protective structure according to claim 1 or 2, wherein the protective structure contains a dye or a pigment.   The protective structure according to claim 1, wherein the protective structure is designed using optical calculation.

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