Side-light back-direction synergistic photovoltaic system

Abstract

The invention provides a side-light back-direction synergistic photovoltaic system. A side-light reflecting plate and a relay reflecting plate are mounted beside and below a double-sided photovoltaic panel; sunlight which directly irradiates the side light reflecting plate is reflected to the relay reflecting plate and then turns to the back face of the double-face photovoltaic plate, so that the back face of the double-face photovoltaic plate receives light to generate power. The power generation efficiency is improved, and the cost per kilowatt-hour is reduced.

Description

Technical Field

[0001] The present application belongs to the field of new energy technologies such as photovoltaic power generation, and specifically relates to a side-lighting back-efficiency photovoltaic system that can reflect direct sunlight around photovoltaic panels to the back of double-sided photovoltaic panels to improve the efficiency of photovoltaic power generation. Background Art

[0002] Bifacial photovoltaic panels are specially designed photovoltaic modules with double-sided power generation capabilities. They can not only generate electricity by absorbing direct light on the front side, but also by absorbing reflected light / scattered light on the back side. There are several application solutions for using the back side of bifacial photovoltaic panels to receive reflected light / scattered light to improve power generation efficiency. First, ground reflection enhancement: set high-reflectivity ground materials such as white stones, reflective films or light-colored coatings under or around the bifacial photovoltaic panels; this design can significantly increase the amount of reflected light received on the back side, especially suitable for deserts, wastelands and areas with abundant light resources. Second, the lifting angle of the bifacial bracket: install the bifacial photovoltaic panel on a specially designed bifacial bracket, and reasonably set the inclination angle according to the geographical location and sunshine conditions, so that both the front and back sides of the photovoltaic panel can receive light more fully; for example, installing it on a bracket at a certain height can increase the receiving angle of the back side, especially suitable for areas with weak light. Third, floating installation on the water surface: floating bifacial photovoltaic panels are installed on the water surface of reservoirs, ponds, lakes, etc., and the light reflected from the water surface is used to illuminate the back side, further increasing the power generation; this method can also utilize the cooling effect of the water body to improve the working efficiency of the components and extend the service life of the photovoltaic panels. Fourth, the agricultural-photovoltaic complementary system: in agricultural areas, bifacial photovoltaic panels are hung above the farmland. The back side can not only utilize the light reflected from the surface, but also avoid the influence of shading on the growth of crops, achieving the dual-purpose effect of agriculture; this application scheme is suitable for agricultural planting and animal husbandry, especially in areas with sufficient sunlight. Fifth, building surface application: bifacial photovoltaic panels are installed on the curtain wall, roof or balcony of the building, so that the back side of the photovoltaic panel can generate electricity using the reflected light and scattered light of the building and its surrounding environment; this scheme is suitable for structures such as high-rise buildings and commercial complexes, especially in urban areas with limited space. Sixth, photovoltaic parking sheds, double-sided photovoltaic panels are installed above the parking lot, and the back side can use the light reflected by the ground and parked vehicles to increase the amount of light received on the back side; this type of solution can not only provide sunshade for the parking shed, but also charge electric vehicles or provide electricity to nearby buildings. It is a multifunctional and efficient way of utilization. Seventh, hillside and wasteland improvement design, double-sided photovoltaic panels are installed in mountainous areas or wastelands with irregular terrain. The inclination angle behind the panel is considered during the design to utilize the reflection effect of the terrain. This method can not only make full use of the land, but also make use of scattered light, which is particularly suitable for areas with strong light on slopes. These solutions improve the power generation efficiency of double-sided photovoltaic panels in different ways, making full use of reflected light and scattered light resources in the natural environment.

[0003] After investigation and testing, the applicant found that the power generation efficiency improved by the current application solutions such as the above-mentioned double-sided photovoltaic panels does not exceed 20% at most. Summary of the invention

[0004] The purpose of this application is to provide a side-to-back photovoltaic system to reflect the sunlight next to the double-sided photovoltaic panel to the back of the double-sided photovoltaic panel (referred to as side-to-back), thereby improving the efficiency of photovoltaic power generation and reducing the cost of electricity.

[0005] In order to achieve the above-mentioned purpose of the invention, the present application provides a side-to-back photovoltaic system as follows.

[0006] The present application provides a side-lighting back-efficiency photovoltaic system, including a double-sided photovoltaic panel that receives direct sunlight for power generation, characterized in that: a side-lighting reflector and a relay reflector are installed next to and below the double-sided photovoltaic panel to form a reflector; the sunlight directly incident on the side-lighting reflector is reflected to the relay reflector and then turned to the back of the double-sided photovoltaic panel, so that the back of the double-sided photovoltaic panel receives light for power generation. In short, the reflector formed by the side-lighting reflector and the relay reflector allows the sunlight next to the double-sided photovoltaic panel to bypass the back of the panel to increase power generation.

[0007] Preferably, the side-lighting back-efficiency photovoltaic system is characterized in that: from front to back (the position closer to the double-sided photovoltaic panel is the back, and the position farther from the double-sided photovoltaic panel is the front), and from top to bottom, the side-lighting reflector gradually lowers into an inclined surface, including an inclined curved surface.

[0008] Preferably, the side-light-to-back photovoltaic system is characterized in that: from front to back and / or from center to periphery, the relay reflector is gradually raised to form an inclined surface, including an inclined curved surface.

[0009] Preferably, the side-lighting back-efficiency photovoltaic system is characterized in that the relay reflector is a diffuse reflector.

[0010] Preferably, the side-lighting back-to-back photovoltaic system is characterized in that a water outlet gap is provided at a low-lying part of the inclined surface of the relay reflector plate to allow rainwater and cleaning wastewater to flow out.

[0011] Preferably, the side-light back-efficiency photovoltaic system is characterized in that the side-light reflector and the relay reflector form a concave reflector. Preferably, the concave reflector is also used as a support for the double-sided photovoltaic panel to replace the current photovoltaic bracket. The side-light reflector and the relay reflector are preferably made into a bathtub-shaped concave reflector rigid body, which is also used as a support for the double-sided photovoltaic panel to replace the current photovoltaic bracket.

[0012] Compared with the prior art, the present application has the following beneficial technical effects.

[0013] First, the reflector composed of the side-light reflector and the relay reflector can reflect the sunlight next to the double-sided photovoltaic panel to its back side (i.e. side-light to back), so as to collect and utilize the sunlight that would otherwise be wasted, thereby improving the power generation efficiency of the system. Tests show that the power generation efficiency of the system has been improved by 15-35%.

[0014] Second, the ratio of the increased 15-45% of electricity to the investment in the side-light reflector and the relay reflector, that is, the investment cost of back-side power generation, is less than the investment cost of purchasing photovoltaic panels with the same investment for only front-side power generation, thus significantly reducing the cost of photovoltaic power generation. For example, if you invest 100 yuan, if you purchase a new single-sided photovoltaic panel, you can purchase (add) 145 watts (that is, 1 / 4 of a nominal 580-watt photovoltaic panel); and if you spend 100 yuan to set up the reflector composed of the side-light reflector and the relay reflector in this application, which is used to direct the sunlight next to it to the back of the nominal 580-watt double-sided photovoltaic panel, you can add 261 watts of power generation, which saves 80% of the investment cost.

[0015] Third, when the double-sided photovoltaic panel is mounted on a rigid body such as a bathtub-shaped concave reflector, the rigid body can also be used as a support for the double-sided photovoltaic panel, which can replace the current photovoltaic bracket. That is, the present application can combine the current bracket and reflector into one, so as to save the comprehensive cost of the bracket, reflector and construction cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the top view of the appearance effect of a side light reflector and a relay reflector used in combination in the present application (Example 1).

[0017] Figure 2 for Figure 1 Schematic diagram of the longitudinal section structure at the AB position.

[0018] Figure 3 To adopt Figure 1 A schematic diagram of the top view of the double-sided photovoltaic panel array with side light reflectors and relay reflectors is shown.

[0019] Figure 4 A bathtub-type reflector consisting of a side-light reflector and a relay reflector.

[0020] Figure 5 for Figure 4 Schematic diagram of the effect of the bathtub-shaped reflector also serving as a support (or bracket) for double-sided photovoltaic panels.

[0021] Figure 6 for Figure 5 Schematic diagram of the effect of adding a transparent cover to the bathtub-shaped reflector.

[0022] Explanation of the accompanying figures: 1-side light reflector, 2-relay reflector, 3-reflector, 4-water outlet, 5-double-sided photovoltaic panel, 6-sunlight, 7-ground, 8-transparent cover. DETAILED DESCRIPTION

[0023] In order to make the technical means, creative features, objectives and effects achieved by this application easy to understand, this application is further explained below in conjunction with specific implementation methods.

[0024] Embodiment 1.

[0025] like Figure 1 , Figure 2 As shown, a side light reflector 1 and a relay reflector 2 are installed beside and below the double-sided photovoltaic panel 5; the sunlight 6 directly hitting the side light reflector 1 is reflected to the relay reflector 2 and then turned to the back of the double-sided photovoltaic panel 5, so that the back of the double-sided photovoltaic panel 5 receives light and generates electricity. In short, the reflector 3 composed of the side light reflector 1 and the relay reflector 2 allows the sunlight 6 beside the double-sided photovoltaic panel 5 to bypass the back thereof, so as to increase the power generation. For example, a bathtub-shaped reflector 3 with a reflectivity greater than 95% and a coating on the inner wall can be made of hard materials such as PVC.

[0026] Preferably, from front to back (the position closer to the double-sided photovoltaic panel 5 is the back, and the position farther from the double-sided photovoltaic panel 5 is the front), and from top to bottom, the side light reflection plate 1 gradually lowers to form an inclined surface, including an inclined curved surface.

[0027] Preferably, from front to back or / and from center to periphery, the relay reflector 2 is gradually raised to form an inclined surface, including an inclined curved surface.

[0028] Preferably, the relay reflector 2 is a diffuse reflector for evenly distributing (i.e., evenly reflecting) the sunlight 6 to the back side of the double-sided photovoltaic panel 5 .

[0029] Preferably, a water outlet 4 such as a water outlet gap is provided at a low-lying part of the relay reflector 2 (slope) for allowing rainwater 7 and cleaning wastewater to flow out.

[0030] Finally, if Figure 3 As shown, a large number of double-sided photovoltaic panels 5 and their reflectors 3 are laid on the existing photovoltaic brackets, and the connecting wires, brackets, inverters, junction boxes, energy storage batteries and other components required by the current photovoltaic power generation system are configured to build a centralized ground photovoltaic power station.

[0031] Embodiment 2.

[0032] refer to Figure 1 , Figure 2 , based on the above example, if Figure 4As shown, the side light reflector 1 and the relay reflector 2 are further made into a bathtub-shaped concave reflector 3 rigid body, which is used as a support body for the double-sided photovoltaic panel 5 to replace the bracket (not shown). It is best to stick a reflective film on the inner wall of the bathtub as the side light reflector 1 and the relay reflector 2.

[0033] Finally, if Figure 5 As shown, the double-sided photovoltaic panel 5 is mounted on a heavy rigid body such as a bathtub-shaped concave reflector 3, which is used as a support body for the double-sided photovoltaic panel 5 instead of a bracket, and the bracket and the reflector 3 are combined into one. Since the rigid body is very heavy, it can be stable by its own weight, so it can be placed on the ground without piling or making a very solid foundation. In this way, the cost of the bracket and the construction cost can be saved. Then, the components such as the connecting wires, brackets, inverters, junction boxes, energy storage batteries, etc. that the current photovoltaic power generation system should have are configured to build a centralized ground photovoltaic power station.

[0034] Best, if Figure 6 As shown, a transparent cover plate 8 , such as a transparent glass plate, is added to the area above the side light reflection plate 1 to prevent dust from contaminating the side light reflection plate 1 and the relay reflection plate 2 .

[0035] What is disclosed above is only a preferred embodiment of the present application. The drawings are merely schematic structural diagrams and are not drawn according to the actual size ratio. They cannot be used to limit the scope of rights of the present application. Equivalent changes made based on the claims of the present application still fall within the scope covered by the present application.

Claims

1. A side-lighting back-lighting photovoltaic system, comprising a double-sided photovoltaic panel for generating electricity by receiving direct sunlight on the front side, characterized in that: A side-light reflector and a relay reflector are installed next to and below the double-sided photovoltaic panel; sunlight directly hitting the side-light reflector is reflected to the relay reflector and then turns to the back of the double-sided photovoltaic panel.

2. The side-lighting back-lighting photovoltaic system according to claim 1, characterized in that: From front to back and from top to bottom, the side light reflection plate gradually lowers to form an inclined surface, including an inclined curved surface.

3. The side-light back-lighting photovoltaic system according to claim 2, characterized in that: From front to back and / or from center to periphery, the relay reflector is gradually raised to form an inclined surface, including an inclined curved surface.

4. The side-lighting back-lighting photovoltaic system according to claim 3, characterized in that: A water outlet gap is provided at the low-lying part of the inclined surface of the relay reflector plate to allow rainwater and cleaning waste water to flow out.

5. The side-lighting back-to-back photovoltaic system according to claim 1, 2, 3 or 4, characterized in that: The relay reflector is a diffuse reflector.

6. The side-lighting back-to-back photovoltaic system according to claim 1, 2, 3 or 4, characterized in that: The side light reflector and the relay reflector form a concave reflector.

7. The side-lighting back-lighting photovoltaic system according to claim 6, characterized in that: The concave reflector also serves as a support for the double-sided photovoltaic panels.

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