JPH10294485A - Module for large size solar cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for maintaining the physical strength of a solar cell module without considerably increasing the number of the constituent members of a solar cell panel when increasing the area of the solar cell panel, and hence, to provide a solar cell module which is light in weight and low in cost and has excellent output characteristics. SOLUTION: A solar cell module 1 comprises a solar cell panel 2 including a solar cell element, a frame 3 for fixing the outer edges of the solar cell panel 2, and a means for outputting power from the solar cell panel 2. The solar cell module 1 has a structure wherein a single or a plurality of ribs 6 are provided for the frame 3 to support and fix the side surfaces of the solar cell panel 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell module used for photovoltaic power generation, and more particularly to a large-area large-sized solar cell module.

[0002]

2. Description of the Related Art In recent years, practical use of a photovoltaic power generation system and development of cost reduction technology have been promoted. In particular, thin-film solar cells are drawing attention as next-generation solar cells. Thin-film solar cells require less raw materials for manufacturing than single-crystal silicon solar cells and polycrystalline silicon solar cells, and can be easily fabricated directly on insulator substrates as large-area integrated solar cells. Therefore, it is attracting attention as a low-cost solar cell. Thin-film solar cells include
Thin-film polycrystalline silicon solar cells, amorphous silicon solar cells, compound polycrystalline solar cells (CdS, CdTe, C
(IGS), among which amorphous silicon solar cells are the most practically used. However, the amorphous silicon solar cell has a problem that when used outdoors for a long time, a phenomenon that conversion efficiency is reduced due to the influence of sunlight, that is, so-called light deterioration occurs. For this reason, conventional practical examples are limited to applications used indoors, such as calculators and watches.

[0003] In recent years, although light degradation has not become zero,
2. Description of the Related Art Amorphous silicon solar cells having a high conversion efficiency after photodegradation of about 10% have been developed. Along with this, the demand for a solar cell power generation system used outdoors, such as mounting solar cells on a roof to cover household power, is increasing.
Such a solar cell is used not in the form of a single photoelectric conversion element (solar cell element) but in the form of a solar cell panel having mechanical strength and weather resistance. This solar cell panel is used in the form of a solar cell module by being fitted into a frame. As shown in FIG. 9, a conventional solar cell module 21 includes a solar cell panel 22 and this panel 22.
And a terminal box 24 for extracting photoelectrically converted power from the panel. The frame-shaped frame is used for panel protection and for installation on a roof or the like. The material of the frame is often made of aluminum alloy or resin.

[0004]

However, in the conventional large-sized solar cell module, the aluminum alloy constituting the frame is excellent in weather resistance and light in weight compared with iron or the like, but is an expensive material. This is one of the causes for increasing the manufacturing cost of the solar cell module. Also,
Even when using a resinous material, the extrusion molding method has a lower limit on the thickness of the frame components, and the thickness cannot be reduced any more. It has contributed.

Although the use of a large-sized module is advantageous in terms of simplifying wiring and increasing the power generation area, in order to maintain the strength of the module, it is necessary to increase the thickness of the frame-like frame or to increase the panel structure. It is necessary to increase the thickness of the members and use lightweight and strong materials such as special tempered glass, which results in an increase in the overall weight and a reduction in the number of components compared to using multiple small-area panels. It was easy to lead to increased costs. Moreover, in the case of a solar cell panel using a transparent member such as a glass plate on the light incident side, if the thickness of the transparent member is increased to obtain the required strength, the amount of light incident on the solar cell element is increased due to an increase in light absorption accompanying the thickness. And the photoelectric conversion efficiency is greatly reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and when increasing the area of a solar cell panel, the thickness of the solar cell panel is hardly increased without increasing the thickness of the components. It is an object of the present invention to provide a means for maintaining the mechanical strength of a battery module, thereby providing a lightweight, inexpensive, solar cell module having excellent output characteristics.

[0007]

In order to achieve the above object, a large-sized solar cell module according to the present invention comprises a solar cell panel including a solar cell element and a frame-like frame for fixing an outer edge of the solar cell panel. And a means for outputting power from the solar cell panel, wherein one or more ribs are provided on the frame to support and fix the side surface of the solar cell panel. Having a configuration.

More specifically, a method of arranging one or more ribs in a cross shape or a ladder shape on a frame-shaped frame, or a method of arranging one or more ribs in a brace shape is adopted. Then, the mechanical strength of the module increases.
In addition, it is preferable to provide a heat insulating material on the back surface side of the solar cell panel to configure the solar cell module in that the annealing effect is promoted. Further, when the cross-sectional shape of the rib is I-shaped or H-shaped, or a hollow cylindrical shape, a hollow triangular shape, or a hollow rectangular shape, the mechanical strength of the rib is increased, and the mechanical strength of the module is improved.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments of a solar cell module according to the present invention will be specifically described below with reference to the drawings. FIG. 1 is a diagram when the large-sized solar cell module 1 according to the present invention is viewed from the back side. The solar cell module 1 includes a solar cell panel 2, a foam base material 8 provided on a back surface of the solar cell panel 2, and a terminal box 5 serving as a unit for outputting power from the solar cell panel 2.
And a frame-shaped frame 3 for holding the outer edge of the solar cell panel 2, and ribs 6 fixed to the frame-shaped frame 3. The ribs 6 serve to support the foam base material 8 and the back surface of the solar cell panel 2, prevent deformation of the module, increase rigidity, and increase the strength of the module. The rib 6 employs an aluminum rod having an H-shaped cross section. The frame 3 is made of aluminum alloy constituent members 3a to 3 made by roll forming.
d is formed by joining the rectangular shape according to the outer edge shape of the solar cell panel.

FIG. 2 is a sectional view taken along the line AA of the solar cell module 1 shown in FIG. 1. FIG. 3 shows that the solar cell panel 2, the H-shaped ribs 6, and the frame 3 are fixed to each other. It shows how it is being done. Solar cell module 1
Is formed by sequentially laminating a solar cell panel 2, an acrylic foam base material 8 having excellent cushioning and heat insulating properties, and an H-shaped rib 6, which are fitted into and adhered to the frame 3. is there. Here, the back surface of the solar cell panel 2 and the foam base material 8, and the foam base material 8 and the H-shaped rib 6
Is adhesively fixed to each other with a double-sided tape using an acrylic adhesive. When sandwiched between the panel 2 and the H-shaped rib 6, the foam base material 8 also serves to absorb a part of the external force applied to the solar cell module and to enhance an annealing effect described later. The outer edge of the solar cell panel 2 is fitted and bonded to the grooves 4a, 4a formed in the upper portion of the frame-shaped frame with an adhesive 7 such as butyl rubber, and both ends of the rib 6 are formed of an adhesive resin. It is fitted and bonded to the grooves 4b, 4b formed in the lower part of the frame. However, in the present invention, the method of fixing the end of the rib and the groove 4b formed in the lower part of the frame is not limited to the method using an adhesive resin, and a method of simply fixing with a screw may be adopted. The frame 3 is provided with holes 9, 9 for mounting the solar cell module 1 on a rooftop or the like.

As described above, by adopting the structure in which the ribs are provided on the frame-shaped frame, the mechanical load applied to the glass plate is reduced, so that the thickness of the glass plate can be reduced. Increasing the thickness of the glass increases light absorption, especially at wavelengths in the near-infrared region, and this loss also reduces the problem of panel power generation characteristics. You do it.

In the solar cell panel 2, a light-transmitting substrate 10 made of a glass plate or the like is disposed on the light incident side, and a photoelectric conversion element 11 including an amorphous silicon film is provided on the back surface of the light-transmitting substrate 10. It is configured by sequentially laminating a filler 12 having adhesive properties and a sealing material 13 for protecting the surface opposite to the light incident side. Here, the filler is EVA
(Ethylene vinyl acetate), PVB (polyvinyl butyral), polyisobutylene-based resin, silicone resin, etc., and the sealing material is Tedlar (registered trademark of DuPont in the form of polyvinyl fluoride), or this Tedlar and aluminum foil A material laminated in a sandwich shape or the like is used.

In this embodiment, an amorphous semiconductor solar cell element is adopted as the most preferable photoelectric conversion element 11. This is because, as described above, thin-film solar cells typified by amorphous solar cells require less raw materials and can be manufactured at lower cost than single-crystal silicon solar cells and polycrystalline silicon solar cells. This is because it has an advantage that it can be easily formed directly on an insulator substrate as an integrated solar cell having a large area. In addition, if the cell area is large, the cost of attaching the solar cell to the gantry and the like can be reduced, which can contribute to the cost reduction of the solar cell module production. When a solar cell panel (for example, Japanese Patent Application Laid-Open No. 7-297435) to which a heat insulating material is adhered to produce an annealing effect is employed, providing a rib on a frame-shaped frame increases the strength of the solar cell module. By increasing the amount of the heat insulating material, the shape of the heat insulating layer can be more effectively determined, and the annealing effect can be improved.

However, in the present invention, a CdTe / CdS solar cell and a CIGS (Cu (InGa) Se ₂ ) solar cell can be adopted as the thin-film solar cell. These have characteristics that conversion efficiency can be made higher than that of amorphous silicon solar cells and that there is little light degradation, but they also have the disadvantage that they contain Cd and In and therefore easily affect the environment. In addition, solar cells such as a structure in which a thin-film solar cell element is directly formed on glass, a structure having a crystalline solar cell element other than a thin-film solar cell element, and a structure in which a flexible element is attached to an iron plate as a solar cell panel. It is also possible to apply all those having a plate-like shape having the above function.

The material of the frame is not limited to aluminum alloy. In addition, it is also possible to adopt a frame-shaped frame made of wood, steel, or synthetic resin, and further, in order to improve weather resistance, a vinyl chloride resin, a fluorine resin, an acrylic resin, or the like. It is also possible to use a metal plate covered with a resin film consisting of The cross section of the rib is not limited to the H-shape, and it is also effective to use a rib having an I-shape. Like the I-type and H-type rods, it is preferable that the material is collected at a position far from the neutral surface of the rod to the extent that buckling and twisting do not occur, because the strength of the rod increases. Furthermore, adopting a hollow cylinder, a hollow triangular prism, a hollow quadrangular prism, or the like as the rib is also effective from the viewpoint of the mechanical strength of the rib.

In FIG. 1, one rib is hung between the constituent members 3c-3d of the frame-shaped frame, and both ends thereof are fixed. However, the number of ribs fixed to the frame is not limited to one, and a plurality of ribs may be used. The method of arranging the ribs is not limited to that shown in FIG. 1 and may be various as shown in FIGS. Is possible. In FIG. 4, two ribs are placed between the components 3c-3d in a ladder-like manner at positions that divide these components into three equal parts. In FIG. 5, two ribs are provided between the constituent members 3c and 3d and between the constituent members 3a and 3b.
It is crucifixed at an intermediate position between these components. FIG. 6 shows a state in which one rib is bridged between the frame-shaped frame diagonally.

A comparison experiment between the large-sized solar cell module according to the present invention shown in FIGS. 1, 4 and 5 and a conventional solar cell module without using a rib in a frame-shaped frame will be described below. In this experiment, when the surface of the solar cell module was subjected to a wind pressure at a wind speed of 60 m, the degree of displacement of the central portion of the glass plate, which is a translucent substrate, was measured. In general, the displacement of the central part of the glass plate which is a translucent substrate does not exceed the thickness of the glass plate,
It is said to be within safety standards. The solar cell module 1 shown in FIGS. 4 and 5 uses the same structure as the solar cell module shown in FIG. 1 except for the method of arranging the ribs and the thickness of the glass plate. The solar cell module used in this comparative test had a size of one meter square.

FIG. 7 is the same sectional view as FIG. 2, but without the ribs. As shown in this figure, the panel used was a square with a side length S of about 1000 mm, and the frame had a thickness of about 1 mm, a height H of about 30 mm, The lateral width T1 of the fixing portion 14a and the intermediate fixing portion 14b is substantially
7 mm, the width T2 of the lower fixing portion 14c was approximately 20 mm, and the width D1 of the groove formed in the upper portion of the frame-like frame was approximately 2 mm added to the thickness of the glass plate. FIG. 8 shows FIG.
It is a figure which shows the cross section of the rib used in FIG. 4, and FIG.
As shown in this figure, the rib has a thickness of approximately 2 mm and a width k of approximately
A 20 mm one was used. Table 1 shows the results of the comparative test.

[0019]

[Table 1]

Here, the first embodiment corresponds to the module structure of FIG. 1, the second embodiment corresponds to FIG. 4, and the third embodiment corresponds to the module structure of FIG. In the case of the conventional example, the thickness of the glass is
I needed a 6mm one. However, in the case of the present invention, in order to be within the safety standards, the case of Example 1 has a plate thickness of 4 mm,
It can be seen that sufficient strength can be obtained with a plate thickness of 3 mm in the case of Example 2 and 2 mm in the case of Example 3, and that the thickness of the glass can be reduced by at least about 30% to reduce the weight. I understood. Therefore, as described above, in the case of a solar cell panel having a structure with glass on the surface, it is possible to reduce the thickness of the glass, improve the power generation efficiency of the panel, and provide an amorphous layer provided with a heat insulating layer. In the case of a high-quality semiconductor solar cell panel, the degree of freedom in determining the amount of heat insulating material and the shape of the heat insulating layer is increased, so that the effect of annealing can be enhanced.

Further, in the present invention, it is needless to say that a combination of the rib arrangements shown in FIGS. 1 to 4 can be used. By combining the shapes of the ribs in this manner, the load applied to the ribs is dispersed, so that a thinner rib can be employed.

[0022]

As described above, according to the present invention, when the solar cell panel is made to have a large area by providing the frame-shaped frame with ribs, the members constituting the solar cell panel, especially the light-transmitting substrate are provided. Since the mechanical strength can be maintained without increasing the thickness of the glass plate, it is possible to manufacture a lightweight and low-cost solar cell module, and it is also possible to reduce the thickness of the glass plate. In addition, absorption of incident light at wavelengths in the near-far infrared region is reduced, and a solar cell panel having excellent output characteristics can be manufactured. Furthermore, because the mechanical load on the solar panel is reduced,
Since the degree of freedom in determining the amount of the heat insulating material and the shape of the heat insulating layer is increased, the effect of the annealing can be enhanced.

A method in which one or a plurality of ribs are arranged in a cross shape or a ladder shape on a frame-shaped frame,
When a method in which one or a plurality of ribs are arranged in a strut is provided, the mechanical strength of the module is increased, and the above-described effect can be further enhanced. Furthermore, when the cross-sectional shape of the rib is an I-shape or an H-shape, or a hollow cylindrical shape, a hollow triangular shape, or a hollow square shape, the mechanical strength of the rib and the solar cell module is improved, and the above-described effect is further enhanced. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of a solar cell module according to the present invention.

FIG. 2 is a diagram showing a cross section AA of the diagram showing the first embodiment.

FIG. 3 is a perspective view showing a joint state of the frame, the panel, and the rib in the first embodiment.

FIG. 4 is a view showing a second embodiment of the solar cell module according to the present invention.

FIG. 5 is a view showing a third embodiment of the solar cell module according to the present invention.

FIG. 6 is a view showing a fourth embodiment of the solar cell module according to the present invention.

FIG. 7 is a cross-sectional view showing a solar cell module.

FIG. 8 is a sectional view of a rib according to the present invention.

FIG. 9 is a view showing a conventional solar cell module.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 solar cell module 2 solar cell panel 3 frame-shaped frame 3 a to 3 b frame component 4 a, 4 b groove formed in frame-shaped frame 5 terminal box 6 rib 7 adhesive 8 foam base material 9 mounting hole 10 light-transmitting substrate 11 photoelectric Conversion element 12 Filler 13 Sealant 14a Upper fixing part 14b Intermediate fixing part 14c Lower fixing part 21 Conventional solar cell module 22 Solar cell panel 23 Frame-shaped frame 24 Terminal box

Claims (5)

[Claims] 1. A solar cell panel having a solar cell element formed on a substrate, a frame-shaped frame for fixing an outer edge portion of the solar cell panel, and one or more ribs fixed to the frame-shaped frame. A single or plural ribs for supporting the solar cell panel from the back side thereof. 2. The frame-shaped frame, wherein one or more ribs are arranged in a cross shape or a ladder shape, or one or more ribs are arranged in a brace shape. The large-sized solar cell module described in the above. 3. The solar battery panel according to claim 1, wherein a heat insulating material is provided on the back side of the solar cell panel.
The large-sized solar cell module described in the above. 4. The large-sized solar cell module according to claim 1, wherein said rib has an I-shaped or H-shaped cross-sectional shape. 5. The large-sized solar cell module according to claim 1, wherein the rib has a cross-sectional shape of a hollow cylinder, a triangle, or a square.