CN111987975A

CN111987975A - High-efficiency solar module assembly

Info

Publication number: CN111987975A
Application number: CN202010438853.9A
Authority: CN
Inventors: 潘威
Original assignee: Dwp Energy Ltd
Current assignee: Dwp Energy Ltd
Priority date: 2019-05-22
Filing date: 2020-05-22
Publication date: 2020-11-24

Abstract

The high efficiency solar module assembly of the present invention includes a frame having an upper portion, the frame including a region, a middle portion disposed below the upper portion. The solar cell panels are arranged into a string and clamped between the two pieces of transparent glass to form the solar cell string, and the area occupied by the solar cell panels is smaller than that of the upper part of the solar cell string. Each solar cell string has a pair of opposing edges. The reflector is arranged in the middle of the frame and can selectively reflect light rays.

Description

High-efficiency solar module assembly

Technical Field

The present invention relates to a highly efficient solar panel, in particular for mounting on the roof of a building or greenhouse.

Background

Solar radiation collecting and converting devices, intended to collect as much light as possible, appear dark and opaque, and cast shadows under them. They are often placed in open areas away from buildings or other downtown areas where sunlight is required. In recent years, the concept of distributed solar power generation has been adopted globally, and the installation of Building Integrated Photovoltaic (BIPV) devices is on the rise.

Besides the solar cell panel installed on the roof, the semitransparent or transparent solar cell module on the outer surface of the building can be seen everywhere. Very thin amorphous silicon, dye-sensitized and organic photovoltaic solar cell modules can allow a portion of visible light (VIS) and infrared light (IR) to transmit through the panel to the back of the module, collecting only a small portion of uv blue light, which is used for power generation. Although the conversion efficiency is rather low, the aesthetics are not affected by these panels. They are therefore suitable for installation at windows.

Although the appearance is not affected by the transmission through these panels, their relatively low efficiency of light energy conversion affects the overall economics of installing them. Unlike glass curtain films used in energy-saving buildings, which do not absorb ultraviolet and infrared light, transparent photovoltaic panels do not block infrared light. This type of window photovoltaic panel does not meet the requirements of low emissivity windows: in summer, additional energy is required to cool the interior due to infrared radiation from the outside, and in winter, additional energy is required to heat the interior due to loss of internal infrared radiation.

Luminescent solar concentrators are another technology currently under development. It contains a luminescent interlayer that converts sunlight primarily into red light. The red light emitted by the luminescent material is easily used by plants for photosynthesis. However, blue and green light also play an important role in plant growth. While only a part of the red light emitted by the luminescent material enters the greenhouse and is absorbed by the plants. In addition, the luminescent material can convert only ultraviolet and visible light having a wavelength shorter than red light, i.e., having energy higher than red light, and thus this technique cannot efficiently convert and utilize infrared light having energy lower than that of red light.

In order to maintain partial transparency and improve photoelectric conversion efficiency, it may be necessary to sacrifice visual aesthetics to a little. One approach has been to make a partially transparent panel in which opaque silicon cell wafers are placed in a pattern such that a gap is maintained between the wafers. The area covered by the silicon cell wafers can collect and convert light energy into electric energy with higher efficiency, and the gaps between the silicon cell wafers can irradiate the inside through light. Translucent panels of this type have been applied for integration with large structures, such as stadiums, traffic stations. A partially filled silicon cell wafer panel can block a proportion of light (e.g., 50% to 80%) and convert the light into electrical energy. The open area (gap) may also provide internal illumination. Of course, such photovoltaic panels do not have the same aesthetic visual perception as uniformly transparent photovoltaic panels, as the panels cast spot shadows.

One of the applications of transparent and translucent panels is for greenhouses, in which case the aesthetic vision is not important. Greenhouses with glass roofs and sides can be replaced by these panels to allow part of the light to penetrate while the remainder is converted into electrical energy. In recent years, the number of indoor plants in the united states has increased, and vertical planting of large greenhouses for LED lights for green vegetables or large plants has become more popular, with transparent or translucent photovoltaic roofs or sides, and greenhouses that can both plant and generate electricity to compensate for the consumption of electricity.

A solar panel is provided that allows photovoltaic light to be converted into electrical energy while still allowing sufficient light to pass through a location beneath the panel to illuminate the area.

Disclosure of Invention

This section presents the invention in a simplified conceptual form, and the detailed description of the invention is further presented in the following "detailed description". This section is not intended to limit the main features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

In one embodiment, the present invention provides a solar module assembly comprising a frame having an upper portion enclosing an area and a middle portion disposed below the upper portion. A plurality of solar panels are arranged in a string, sandwiched between two transparent glass windows to form a single string of panels. The solar cell panel occupies an area smaller than that of the upper portion. Each of the plurality of solar panels has a pair of opposing edges. The reflector is mounted on the middle portion.

In another embodiment, the present invention provides a solar module assembly comprising a solar panel comprising a plurality of spaced-apart strings of solar cells. Each solar cell string has a top surface, an opposing bottom surface and a pair of opposing edges. A reflector is disposed below each of the strings of solar cells and is configured to reflect light from around the opposing edges onto a bottom surface of each of the strings of solar cells.

In yet another embodiment, the present invention provides a solar module assembly comprising a frame having a planar area and a solar panel mounted to the frame. The solar panel includes a plurality of cells arranged in a solar cell string. The solar panel has a top surface and a bottom surface. The string of solar cells covers only a portion of the planar area. The reflector is mounted on the frame below the solar panel. The reflector is configured to reflect light onto a bottom surface of the solar panel.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention and, together with a general description given above and the detailed description given below, serve to explain the features of the invention. In these drawings:

FIG. 1 is a perspective view of a solar module assembly according to an exemplary embodiment of the present invention;

FIG. 2 is a top view of the solar panel used in FIG. 1;

FIG. 3 is a schematic view of a solar module assembly according to an alternative exemplary embodiment of the present invention;

FIG. 4 is a perspective view of the assembly of FIG. 1 mounted on a greenhouse roof; and

fig. 5 is a schematic view of a solar module assembly according to another alternative exemplary embodiment of the present invention.

Detailed Description

Like numbers refer to like elements throughout. Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present invention. The terminology used includes the words specifically mentioned, derivatives thereof, and words of similar import. The examples set forth below are not intended to be exhaustive or to limit the invention to the precise forms disclosed. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, and to enable others of ordinary skill in the art to best utilize the invention.

Reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. The same applies to the word "implement".

In this patent application, the word "exemplary" is used to mean "exemplary," "example," or "illustrations," but any feature or design described as "exemplary" is not necessarily to be construed as preferred or advantageous over other features or designs, and the word "exemplary" is used instead for the purpose of presenting concepts in a concrete fashion.

Furthermore, the term "or" means an inclusive "or" rather than an exclusive "or". That is, unless otherwise specified, or from the context, "X includes the use of A or B" is intended to mean any of the natural inclusive permutations. That is, if X contains A, X contains B, or X contains both A and B, then "X contains A or B" is satisfied under any of the above circumstances. Furthermore, the terms "a" and "an" as used in this application, and the appended claims, should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form.

The present invention is a high efficiency solar module assembly that can be mounted on top of a greenhouse roof such that a portion of the incident light is directed onto the upper surface of the assembly and the remainder of the incident light passes through the assembly and is reflected by a reflector to the bottom surface of the assembly while the remainder of the incident light passes through the assembly and is directed into the interior of the greenhouse. Although the high efficiency solar module assembly of the present invention can be mounted on a greenhouse, those skilled in the art will recognize that the high efficiency solar module assembly of the present invention does not necessarily have to be mounted on a greenhouse. By way of example only, the high efficiency solar module assembly of the present invention may also be mounted directly on the ground, thereby reducing the impact of the solar module assembly on the local environment by increasing the electrical power generated without increasing the footprint required to generate the electrical power.

Referring to the drawings, a solar module assembly 100 is shown. The assembly 100 includes a frame 102 having an upper portion 104 for mounting a plurality of solar panels 110 thereon. The upper portion 104 surrounds a planar area, as shown in FIG. 2.

The frame 102 also includes a middle portion 106 disposed below the upper portion 102. The middle portion 106 is used to support the reflector 130.

Optionally, the frame 102 may also include a lower portion 108 disposed below the middle portion 106. The lower portion 108 is used to raise the reflector 130 above a surface on which the assembly 100 is mounted, such as a greenhouse roof, the ground, or some other surface.

Each solar panel 110 includes a bifacial photovoltaic silicon cell having a top surface 111 and a bottom surface 112, each surface including a photovoltaic panel configured to receive light energy, thereby increasing the amount of light energy that can be absorbed as compared to a single-sided photovoltaic cell.

Referring to fig. 2 and 3, the solar panels 110 are arranged in a string and are sandwiched between two

transparent glasses

113, 114 on the upper portion 104 of the frame 102, forming a single string of panels having a pair of opposing

edges

116, 118. The solar panel 110 occupies an area that is smaller than the area of the upper portion 104 so that some incident light can pass through the unoccupied area of the upper portion 104. Referring to fig. 2, a plurality of spaced-apart solar cell strings 120 are provided on a panel 110. The solar cell strings 120 each have a top surface 122 and a bottom surface 124.

Adjacent solar cell strings 120 are spaced apart such that the solar cell strings cover only a portion of the planar area of the panel 110, with a gap 126 disposed between the first and second solar cell strings 120, 120. The region between each solar cell string 120 and one of the opposing

edges

116, 118 is free of solar cell strings so that incident sunlight can pass through the region to the reflector 130. In an exemplary embodiment, the solar cell strings 120 may be arranged in a stripe pattern as shown in fig. 2. Alternatively, the solar cell strings 120 may be arranged in a checkerboard pattern or any other pattern as desired.

In an exemplary embodiment, the solar cell string 120 covers approximately 50% of the area of the frame 102, while the remaining 50% is free of the solar cell string 120, such that light passing between the solar panels 120 may be reflected onto the bottom surface 124 of the solar cell string 120. In an exemplary embodiment, with a 50% -50% division ratio and a 20% conversion efficiency of the silicon panel as described above, light incident on the top surface 122 of the solar cell string 120 may be converted by about 100W/m²And light incident on the bottom surface 124 of the solar cell string 120 may be converted to about 40W/m². However, one skilled in the art will recognize that the ratio of 50% -50% can be varied as desired. Alternatively, using equation 1 below, the amount of power that can be converted from light incident on the bottom surface 124 of the solar cell string 120 can be calculated as:

wherein,

L_Ois the optical loss, mainly the reflection loss, from air to the glass surface;

f is the fractional area covered by the PV panel in a unit area. Thus, 1-f represents the open gap region area;

EQE stands for external quantum efficiency, which describes the PV material's ability to convert photons into electron-hole pairs;

q is the electronic charge, equal to 1.6E-19 coulombs;

voc is the open circuit voltage of the photovoltaic panel;

FF is the fill factor of the photovoltaic panel, describing the resistive loss of the PV panel;

LR is optical losses associated with the reflector, such as reflection losses, losses due to optical errors, etc.; and

BF is a bifacial factor for bifacial silicon cells and describes the difference in conversion efficiency between the front and back of a PV panel.

L_RIs the optical losses associated with the reflector, such as reflection losses, losses due to optical errors, etc.;

BF is the bifacial ratio of bifacial silicon cells, which describes the difference in the conversion efficiency of the front and back sides of a photovoltaic panel.

The reflector 130 is mounted on a middle portion of the frame 102 below the panels 110 and is configured to selectively reflect light passing through an upper area without the plurality of solar panels 110 onto the bottom surface 112 of the solar panel. While a single reflector 130 is shown in fig. 1 across the width of the frame 102, those skilled in the art will recognize that a plurality of smaller reflectors 131 may be mounted adjacent to one another to reflect light off or through the reflectors 131, as shown in fig. 3. The reflectors 131 may be identical to each other, or alternatively, the reflectors 131 may have a different shape from the other reflectors 131, so that the incident sunlight may be better reflected using a different shape according to the movement of the sun around the assembly 100.

A reflector 130 is disposed below each solar cell string 120 and is configured to reflect light from around the opposing

edges

116, 118 passing through adjacent solar panels 110 onto the bottom surface 124 of each solar cell string 120.

The reflector 130 is configured to reflect light having a selective or tunable wavelength band between about 700 nanometers and about 1100nm, and to allow light having a wavelength less than about 700nm to pass through the reflector 130. Light having a wavelength between 700nm and 1100nm is reflected for conversion into electrical energy to increase the efficiency of the solar cell.

The reflector 130 may be tuned by selectively applying or coating a dichroic layer on the reflector 130. The tunability of the reflector 130 can be adjusted by removing the existing dichroic layer on the reflector 130 and applying a different dichroic layer.

When the assembly 100 is mounted on a greenhouse 50, as shown in fig. 4, visible light (400 nm to 700 nm) passes through the reflector 130 and reaches the growing plants within the greenhouse 50 to photosynthesize the plants and illuminate the interior of the greenhouse 50. The light in the 700nm to 1100nm range reflected back to the solar cell panel 110 is not used by the plants but is used to generate electricity.

In one exemplary embodiment, as shown in FIG. 1, reflector 130 has an arcuate cross-section, while in another exemplary embodiment, as shown in FIG. 5, reflector 130 'has a textured surface 131' configured to diffuse visible light. Although not shown, other configurations of the reflector 130 may be hyperbolic, arcuate, or elliptical. Additionally, the reflector 130 may be a retro-reflector, a planar diffuser, or other shape that may reflect at least a portion of the light incident thereon onto the bottom surface 124 of the solar cell string 120.

Those skilled in the art will understand, appreciate, and modify the embodiments described hereinabove, but any modification does not depart from the broad concepts described herein. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A solar module assembly comprising:

a frame having a frame upper portion including a region, and a middle portion disposed below the upper portion;

a plurality of solar panels arranged in a string sandwiched between two transparent glasses to form a single string of solar cells, wherein the area occupied by the plurality of solar panels is less than the area of the upper portion, each solar panel having a pair of opposing edges;

and

a reflector mounted in the middle of the frame.

2. The solar module assembly of claim 1 wherein the plurality of solar panels have a top surface configured to receive light energy and a bottom surface configured to receive light energy.

3. The solar module assembly of claim 2, wherein the reflector is configured to selectively reflect light onto a bottom surface of the solar panel.

4. The solar module assembly of claim 1 wherein the reflector has an arcuate cross-section.

5. The solar module assembly of claim 1 wherein the reflector has a textured surface.

6. The solar module assembly of claim 3 wherein the reflector is configured to reflect light having a selective wavelength band between about 700 nanometers and about 1100 nanometers.

7. The solar module assembly of claim 5 wherein the reflector is configured to allow light having a wavelength of less than about 700 nanometers to pass through the reflector.

8. The solar module assembly of claim 2 wherein the upper portion of the frame has an upper area where the plurality of solar panels are not disposed on opposite edges of the solar cell.

9. The solar module assembly of claim 7, wherein the reflector is configured to reflect light passing through the upper region where the plurality of solar panels are not disposed to a bottom surface of the solar panel.

10. The frame of claim 1 further comprising a lower portion disposed below the middle portion of the frame.

11. A solar module assembly comprising:

a solar panel comprising a plurality of spaced solar cell strings, each solar cell string having a top surface, and opposing bottom surface and a pair of opposing edges, and

a reflector disposed below each of the strings of solar cells and configured to reflect light rays passing around the opposite edges to a bottom surface of each of the strings of solar cells.

12. The solar module assembly of claim 11 wherein the reflector reflects light at wavelengths greater than 700 nanometers and allows light at wavelengths less than 700 nanometers to pass through the reflector, the reflector being tunable in the reflection band.

13. The solar module assembly of claim wherein the reflector has an arcuate cross-section.

14. The solar module assembly of claim wherein the reflector has a textured surface.

15. The solar module assembly of claim 11, wherein the solar modules are mounted on a frame, wherein the region between two adjacent strings of solar cells is free of strings of solar cells.

16. The solar module assembly of claim 15 wherein the reflector is mounted on a frame below the solar panel.

17. A solar module assembly comprising:

a frame having a planar area;

a solar panel mounted on the frame, comprising a plurality of solar cells arranged in a string, the solar panel having a top surface and a bottom surface, wherein the string of solar cells covers only a portion of the planar area;

and

a reflector mounted on the frame below the solar panel for reflecting light to a bottom surface of the solar panel.

18. The solar module assembly of claim 17 wherein the top and bottom surfaces each comprise a photovoltaic panel.

19. The solar module assembly of claim 17, wherein a gap is left between two strings of solar cells.

20. The solar module assembly of claim 17 wherein the reflector allows visible light to pass through the reflector and is configured to scatter visible light.