A production process of a low-magnification concentrating solar thermal cogeneration system

Abstract

The present application relates to the field of photovoltaics, in particular to a low-multiple light concentration solar combined heat and power production process, comprising the following steps: cell assembly manufacturing, dividing whole silicon wafer into small cell pieces by mechanical or chemical method, then connecting the small cell pieces in series and parallel, and connecting each small series or several small series in parallel with bypass diode to form a circuit; the low-multiple light concentration solar combined heat and power assembly is sequentially laminated from top to bottom by transparent layer, first adhesive layer, cell assembly and circuit layer, second adhesive layer, insulation layer, third adhesive layer and heat collecting layer, and then put into a laminator for lamination, the lamination temperature is about 120-145 degrees, the lamination pressure is about 0.2-0.8 kg, and the lamination time is about 8-20 minutes, the present application has the advantages compared with the prior art that the flat plate solar combined heat and power assembly is first designed by circuit to reduce current, and then replaced by low-cost concentrator mirror by using light concentration technology.

Description

Technical Field

[0001] This invention relates to the field of photovoltaics, and more specifically to a production process for a low-concentration solar cogeneration system. Background Technology

[0002] The solar energy in the shaded area on the north side of the flat-plate solar cogeneration module cannot be utilized. By using concentrating technology and a reasonable and ingenious arrangement, this part of the solar energy can be reasonably and fully utilized.

[0003] Solar energy is unbalanced between winter and summer. Summer sunshine hours are about twice as long as winter sunshine hours, resulting in about twice the solar energy output in summer. By using a concentrating design, the solar energy concentration area is increased in winter and decreased in summer, thus achieving a balanced solar energy output between winter and summer.

[0004] Flat-plate solar cogeneration modules draw a relatively large current and will burn out after concentrating sunlight.

[0005] Because the current of crystalline silicon solar cell modules (PV modules) is relatively large (8-13A), they are not suitable for continuous operation under multiple times the light intensity. If they are operated continuously for a long time, the cells will degrade and age quickly, causing them to fail in a short time. To solve the above problems, it is urgent to produce a low-concentration solar cogeneration system that can collect solar energy that cannot be converted into electrical energy as heat energy and then transmit it out for utilization. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the defects of the above-mentioned technology and provide a production process for a low-concentration solar cogeneration system.

[0007] To solve the above-mentioned technical problems, the present invention provides a production process for a low-concentration solar cogeneration system, comprising the following steps: Step 1: Concentrated solar cell module manufacturing. The whole crystalline silicon solar cell is mechanically or chemically divided into several small solar cells. Then these divided small solar cells are connected in series and parallel. Each small string or several small strings are connected in parallel with bypass diodes to form a circuit. Step 2: The low-concentration solar cogeneration system components are laid in layers from top to bottom, consisting of a transparent layer, a first adhesive layer, a battery module and circuit layer, a second adhesive layer, an insulating layer, a third adhesive layer, and a heat collection layer. The layers are then placed in a laminator for lamination. The lamination temperature is between 120-145℃, the lamination pressure is 0.2-0.8MPa, and the lamination time is 8-20 minutes. Step 3: The lower part of the heat collection layer in Step 2 is connected to the heat transmission pipeline; Step 4: Insulation layer fabrication, the heat transfer pipe and heat collection layer are covered with insulation material to reduce heat conduction; Step 5: A protective base plate is attached to the lower part of the insulation layer in Step 4.

[0008] Step 6: Condensing lens fabrication. The bottom surface of the condensing lens consists of a silver layer, a copper layer, and a back coating layer. The unit area mass of the silver layer is greater than 1200 mg / m², the unit area mass of the copper layer is greater than 350 mg / m², and the back coating layer is divided into a base coating layer with a thickness greater than 20 micrometers, a middle coating layer with a thickness greater than 20 micrometers, and a top coating layer with a thickness greater than 20 micrometers. Step 7: The condenser lens composite method involves stacking the condenser lens, adhesive layer, and base plate, then applying heat and pressure using a press to composite and cure them. After curing, they are bonded together. Step 8: Fabrication of the condenser lens support; As an improvement, the transparent layer is made of low-iron, high-transparency ultra-white glass or a fluorine-containing transparent film and other transparent structures.

[0009] As an improvement, the first adhesive layer, the second adhesive layer and the third adhesive layer are all made of polyethylene-polyvinyl acetate copolymer or other adhesive materials.

[0010] As an improvement, the heat collection layer is configured as a plate structure, the heat collection layer is made of a metal material with excellent thermal conductivity, and the surface of the heat collection layer is coated with a selective coating with high heat absorption performance and low heat dissipation performance.

[0011] As an improvement, the insulation material in step 4 is polyurethane foam.

[0012] As an improvement, the heat transfer pipe contains a flowing heat-conducting working fluid.

[0013] As an improvement, the heat transfer pipeline is connected to a heating system, which is equipped with a circulating water pump for controlling the flow rate of the heat transfer medium in the heat transfer pipeline.

[0014] As an improvement, in step 2, the lower part of the heat collection layer is connected to the heat transmission pipeline by welding or bonding with thermally conductive adhesive.

[0015] As an improvement, the condenser lens bracket is formed by extrusion or stretching, and air vents are provided on both sides of the condenser lens bracket. The upper part of the condenser lens bracket is designed as a planar structure or an arc-shaped structure according to the light focusing requirements.

[0016] As an improvement, the condenser lens is composed of a single piece of silver mirror or a strip of silver mirror.

[0017] The advantages of this invention compared to the prior art are: The current of the flat-plate solar cogeneration module is first reduced through circuit design. Then, by using concentrating technology, a low-cost concentrator is used to replace the flat-plate solar cogeneration module, significantly reducing its cost. Next, the concentrator is placed in the shaded area on the north side of the flat-plate solar cogeneration module, creating a seamless connection between the concentrator and the module. This allows for full utilization of solar energy in the shaded area of ​​the module. The flow rate of the circulation pump is controlled by the outlet temperature to ensure temperature stability. Through concentrating technology, the imbalance of solar energy between summer and winter is mitigated. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a crystalline silicon solar cell cutting process; Figure 2 This is a schematic diagram of the battery module structure; Figure 3 This is a schematic diagram of each layer of the solar cogeneration system panel; Figure 4 This is a schematic diagram of the connection between the heat transfer pipe and the heat collector plate; Figure 5 This is a schematic diagram of each layer of the solar cogeneration system panel; Figure 6 This is a schematic diagram of the cross-sectional structure of a solar panel; Figure 7 This is a schematic diagram of the side structure of the support frame; Figure 8 This is a diagram showing the installation of the condenser lens; Figure 9 This is a schematic diagram of a concentrated solar power (CSP) cogeneration system. Figure 10 This is a diagram illustrating the system's usage status. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] In the description of the embodiments of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationships commonly used when the product is in use. These are merely for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] Furthermore, the use of terms such as "horizontal," "vertical," and "suspension" does not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0022] In the description of the embodiments of the present invention, "a plurality of" means at least two.

[0023] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0024] The production process of a low-concentration solar cogeneration system according to the present invention will be further described in detail below with reference to the accompanying drawings.

[0025] Combined with appendix Figures 1-4 A production process for a low-concentration solar cogeneration system includes the following steps: Step 1: Concentrated solar cell module manufacturing. The whole crystalline silicon solar cell is mechanically or chemically divided into several small solar cells. Then these divided small solar cells are connected in series and parallel. Each small string or several small strings are connected in parallel with bypass diodes to form a circuit. Step 2: The low-concentration solar cogeneration system components are laid in layers from top to bottom, consisting of a transparent layer, a first adhesive layer, a battery module and circuit layer, a second adhesive layer, an insulating layer, a third adhesive layer, and a heat collection layer. The layers are then placed in a laminator for lamination. The lamination temperature is between 120-145℃, the lamination pressure is 0.2-0.8MPa, and the lamination time is 8-20 minutes. Step 3: The lower part of the heat collection layer in Step 2 is connected to the heat transmission pipeline; Step 4: Insulation layer fabrication, the heat transfer pipe and heat collection layer are covered with insulation material to reduce heat conduction; Step 5: A protective base plate is attached to the lower part of the insulation layer in Step 4.

[0026] Step 6: Condensing lens fabrication. The bottom surface of the condensing lens consists of a silver layer, a copper layer, and a back coating layer. The unit area mass of the silver layer is greater than 1200 mg / m², the unit area mass of the copper layer is greater than 350 mg / m², and the back coating layer is divided into a base coating layer with a thickness greater than 20 micrometers, a middle coating layer with a thickness greater than 20 micrometers, and a top coating layer with a thickness greater than 20 micrometers. Step 7: The method of condenser lens bonding involves stacking the condenser lens, adhesive layer, and base plate, then bonding them together using a press, heating and pressurizing, and curing them together. Step 8: Fabrication of the condenser lens support; Preferably, the transparent layer is made of low-iron, high-transparency ultra-white glass or a fluorine-containing transparent film or other transparent structures.

[0027] Preferably, the first adhesive layer, the second adhesive layer and the third adhesive layer are all made of polyethylene-polyvinyl acetate copolymer or other adhesive materials.

[0028] Preferably, the heat collection layer is configured as a plate structure, the heat collection layer is made of a metal material with excellent thermal conductivity, and the surface of the heat collection layer is coated with a selective coating with high heat absorption performance and low heat dissipation performance.

[0029] Preferably, the insulation material in step 4 is a polyurethane foam material.

[0030] Preferably, the heat transfer pipe contains a flowing heat-conducting working fluid.

[0031] Preferably, the heat transfer pipeline is connected to a heating system, and the heating system is equipped with a circulating water pump for controlling the flow rate of the heat transfer medium in the heat transfer pipeline.

[0032] Preferably, in step 2, the lower part of the heat collection layer is connected to the heat transmission pipeline by welding or bonding with thermally conductive adhesive.

[0033] Preferably, the condenser lens bracket is formed by extrusion or stretching, the condenser lens bracket has air vents on both sides, and the upper part of the condenser lens bracket is designed as a planar structure or an arc-shaped structure according to the light focusing requirements.

[0034] Preferably, the condenser lens is composed of a single piece of silver mirror or a strip of silver mirror.

[0035] In a specific implementation of this invention, the manufacturing process of the solar combined heat and power system includes the following steps: In battery module manufacturing, a single crystalline silicon solar cell is divided into several equal parts, such as 1 / 2, 1 / 3, 1 / 4, 1 / 5, 1 / 6, 1 / 7, 1 / 8, 1 / n, or even smaller, using mechanical, chemical, or physical methods, such as laser cutting or etching. The current of each divided cell will be 1 / n of the original single cell. The voltage of each cell remains constant due to the characteristics of the semiconductor material: P internal loss = I²R, R = P internal loss / I² = P / (I / N)². The smaller the cell is divided, the smaller R will be, thus reducing P internal loss. These divided cells are then connected in series and parallel. Each small string or several small strings are connected in parallel with bypass diodes to form a circuit. The cells can be cut into small pieces, or they can be of different structures, and different series and parallel connection methods are used. The purpose of reducing the size of the cells is to reduce the current. After concentration, the current increases linearly with the concentration factor. See attached details. Figure 1 .

[0036] The fabrication of the power generation, heat collection, and heat transmission modules is as follows: The first layer is a transparent layer; the second layer is polyethylene-polyvinyl acetate copolymer (EVA film) or POE (POE generally refers to polyolefin elastomers such as ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer, which require metallocene catalysis for production; photovoltaic POE is ethylene-octene copolymer); the third layer is the battery module and circuit layer; the fourth layer is the EVA film; the fifth layer is the insulating backsheet; the sixth layer is the EVA film; the seventh layer is the heat collection plate; the eighth layer is the heat collection and heat transmission pipes; the ninth layer is the insulation layer; and the tenth layer is the backsheet layer.

[0037] For the first layer of glass, low-iron, high-transmittance ultra-clear glass or fluorine-containing transparent film and other transparent materials should be preferred, as this will increase the transmittance of sunlight.

[0038] The second layer is the adhesive layer, preferably made of polyethylene-polyvinyl acetate copolymer (EVA), which has the following characteristics: 1. High transparency and high adhesion, suitable for various interfaces, including glass, metal, and plastics such as PET; 2. Good durability, resistant to high temperatures, moisture, ultraviolet rays, etc.; 3. Easy to store. At room temperature, the adhesion of EVA is not affected by humidity or the absorbency of the film. 4. Low melting point, easy to flow, suitable for various glass lamination processes, such as patterned glass, tempered glass, curved glass, etc.; 5. Tensile strength (MPa) ≥17, visible light transmittance (%) ≥92, elongation at break (%) ≥650, haze (%) 0.6; 6. Bond strength (kg / cm) ≥2; 7. Good radiation resistance, UV cutoff rate 98.5%, good light transmittance; 8. Water absorption (%) ≤0.15; 9. Good heat resistance, moisture resistance, impact resistance, and impact resistance, long service life; allows more sunlight to reach the third-layer battery module; POE (POE generally refers to polyolefin elastomers such as ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer). Elastomer: Multi-layer co-extruded POE film has low water permeability, close to 1 / 5 of that of EVA film of the same thickness, which can significantly improve the weather resistance of modules. At the same time, co-extruded POE film also has the advantages of EVA film in terms of production process, namely high module production yield and high production efficiency, and the film itself is easy to store. Therefore, POE film can improve power generation efficiency when used to encapsulate solar cells.

[0039] The third layer is the battery module and circuit layer, which can be crystalline silicon (monocrystalline or polycrystalline silicon), amorphous silicon, or perovskite cells. First, the large battery cell is divided into numerous smaller cells according to actual needs using processes such as laser cutting or etching. The purpose is to reduce the current of each smaller cell, as the current of a cell is related to its area. These smaller cells are then connected in series, parallel, or series-parallel to form small battery strings. Each small battery string consists of 1 to N divided cells. These small battery strings are then connected in series and parallel, with bypass diodes connected in parallel between the battery strings. These bypass diodes protect the cells; when a cell in the battery module is partially shaded, causing hot spots, the current in that string can flow through the bypass diodes to the next string, preventing the entire battery module from failing to generate power.

[0040] The fourth layer is the EVA adhesive layer, which connects the battery assembly and the insulation layer.

[0041] The fifth insulating layer primarily serves as electrical isolation, separating the third-layer battery module from the seventh-layer heat collector layer. The insulating material is fluorinated materials such as TPT, TPE, and ETFE. TPT polyvinyl fluoride composite films typically employ a three-layer structure (PVF / PET / PVF). The outer protective layer, PVF, offers excellent resistance to environmental corrosion; the middle layer, PET polyester film, provides good insulation; and the inner PVF layer requires surface treatment, while EVA provides good adhesion.

[0042] The sixth layer is an EVA adhesive layer that connects the insulation layer and the heat collection layer.

[0043] The seventh layer is a selectively coated heat collector plate or module. The heat collector plate can be made of aluminum, copper, or other materials with good thermal conductivity. A selective coating is applied to the heat collector plate, which has high heat absorption and low heat dissipation performance, as detailed in the attached diagram. Figure 3 .

[0044] After the above seven layers are laid, they are placed into a laminator for lamination. The lamination temperature is between 120-145℃, the lamination pressure is 0.2-0.8MPa, and the lamination time is 8-20 minutes.

[0045] The eighth layer is the heat transfer layer, through which the collected heat energy is transferred out via heat transfer pipes.

[0046] A. The connection between the heat transfer pipes and the heat collector layer is generally achieved by welding, whereby the heat transfer pipes and the heat collector plates are welded together according to the attached diagram. B. To increase the contact area between the heat transfer pipes and the heat collection layer, and to improve thermal conductivity, structural optimizations were made; see appendix for details. Figure 4 The ninth layer is an insulation layer, which uses polyurethane foam to cover the eighth layer to reduce heat conduction.

[0047] The tenth layer is a protective base plate that protects the foam layer.

[0048] The condenser lens is manufactured by comprising a silver layer, a copper layer, and a back coating layer on its bottom surface. The unit area mass of the silver layer is greater than 1200 mg / m², and the unit area mass of the copper layer is greater than 350 mg / m². The back coating layer is divided into a primer layer with a thickness greater than 20 micrometers, a middle coating layer with a thickness greater than 20 micrometers, and a top coating layer with a thickness greater than 20 micrometers. The silver layer increases the reflectivity, the copper layer protects the silver layer from oxidation, and the primer protects the copper layer from oxidation.

[0049] The composite method of the condenser lens involves stacking the condenser lens, adhesive layer, and base plate in whole pieces or in strips, and then bonding them together using a press. After heating and pressing, the layers are cured and bonded together. The base plate serves to protect the silver mirror and also enhances its structure.

[0050] The construction of the concentrator support requires that there be no shadows on the solar panels, the concentrator modules must be seamlessly connected, and the support must not be blocked by sunlight, so that the concentrator mirrors are stacked together like tiles.

[0051] The bracket used to hold the condenser lens is formed by extrusion or stretching. Vent holes are punched on both sides of the bracket. The bracket is designed according to the condensation requirements and can be straight or curved.

[0052] The system control design takes into account the uneven distribution of solar energy throughout the year, with summer energy production being twice that of winter. Therefore, in summer, heat dissipation is required for the solar panels to reach the design temperature, activating the heat dissipation module. Circulating heating is then implemented, maintaining a constant temperature after reaching the set temperature to collect more heat energy. The flow rate of the circulating pump is controlled to meet design requirements.

[0053] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A production process for a low-concentration solar cogeneration system, characterized in that: Includes the following steps: Step 1: Concentrated photovoltaic cell module fabrication. The entire crystalline silicon solar cell is mechanically or chemically divided into several smaller cells, and then... These segmented small battery cells are connected in series and parallel, and each small string or several small strings are connected in parallel with bypass diodes to form a circuit. Step 2: The low-concentration solar cogeneration system components consist of a transparent layer, a first adhesive layer, a battery module and circuit layer, and a second adhesive layer. The insulation layer, the third adhesive layer, and the heat collection layer are laid in sequence from top to bottom and then placed in a laminator for lamination. The lamination temperature is 120-145℃. During lamination, the pressure is 0.2-0.8 MPa, and the lamination time is 8-20 minutes; Step 3: The lower part of the heat collection layer is connected to the heat transmission pipeline; Step 4: Insulation layer fabrication, the heat transfer pipe and heat collection layer are covered with insulation material to reduce heat conduction; Step 5: A protective base plate is attached to the lower part of the insulation layer; Step 6: Condenser lens fabrication. The bottom layer of the condenser lens consists of a silver layer, a copper layer, and a back coating layer. The unit area mass of the silver layer is greater than 1200 mg / m², and the unit area mass of the copper layer is greater than 350 mg / m². The back coating layer is divided into a primer layer, a middle coating layer, and a top coating layer. The thickness of the primer layer is greater than 20 micrometers; the thickness of the middle coating layer is greater than 20 micrometers; and the thickness of the top coating layer is greater than 20 micrometers. Step 7: The condenser lens is laminated by stacking the condenser lens, adhesive layer, and base plate and then bonding them together using a press. After curing, they are bonded together. Step 8: Fabrication of the condenser lens support.

2. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The transparent layer is made of low-iron, high-transparency ultra-white glass or a fluorine-containing transparent film.

3. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The first adhesive layer, the second adhesive layer and the third adhesive layer are all made of EVA film or POE film.

4. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The insulation material is polyurethane foam.

5. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The heat transfer The inside of the pipe contains a flowing heat-conducting working fluid.

6. The production process of a low-concentration solar cogeneration system according to claim 5, characterized in that: The heat transfer pipeline It is connected to a heating system, which is equipped with a circulating water pump for controlling the flow rate of the heat transfer medium in the heat transfer pipeline.

7. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The lower part of the heat collection layer is connected to the heat transmission pipeline by welding.

8. The production process of a low-concentration solar cogeneration system according to claim 1, characterized in that: The condenser lens bracket is formed by extrusion or stretching. The condenser lens bracket has air vents on both sides. The upper part of the condenser lens bracket is designed as a planar structure or an arc-shaped structure according to the light focusing requirements.

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