Photovoltaic phase change ventilation roof
By incorporating a phase change material layer and a ventilation layer into the photovoltaic roof, the problems of reduced efficiency of photovoltaic panels at high temperatures and heat entering the building are solved, achieving the effects of temperature regulation and energy consumption reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-04-03
AI Technical Summary
Photovoltaic roofs become less efficient in the high temperatures of summer, and the heat entering the building increases building energy consumption.
A phase change material layer is installed below the photovoltaic panel to absorb heat and regulate temperature, and a ventilation layer is installed below the ventilation layer to exhaust heat and prevent heat from entering the house.
Effectively regulates the temperature of photovoltaic panels, maintains efficient operation, reduces heat accumulation inside buildings, and lowers energy consumption.
Smart Images
Figure CN224078527U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of building insulation, specifically a photovoltaic phase change ventilation roof. Background Technology
[0002] During the summer, the high operating temperature of photovoltaic roofs reduces their efficiency. For some lightweight buildings, excessively high solar panel temperatures can lead to increased heat entering the building, resulting in wasted energy. Therefore, roofs with good thermal performance play a positive role in reducing buildings' dependence on fossil fuels and shifting towards cleaner, low-carbon energy supplies. Summary of the Invention
[0003] To overcome the shortcomings of the existing technology, this utility model provides a photovoltaic phase change ventilated roof. The photovoltaic phase change ventilated roof has a phase change material layer set under the photovoltaic panel to absorb the heat of the photovoltaic panel, so as to regulate the temperature of the photovoltaic panel and prevent the photovoltaic panel from becoming less efficient due to excessive temperature. A ventilation layer is set under the phase change material layer to exhaust the heat passing through the phase change material layer and prevent heat from entering the house.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is: a photovoltaic phase change ventilated roof, comprising:
[0005] Photovoltaic panels are used for photoelectric conversion.
[0006] A phase change material layer is disposed below the photovoltaic panel. The phase change material layer can melt and absorb heat when the temperature exceeds a first preset temperature, and release heat and solidify when the temperature drops below a second preset temperature.
[0007] A ventilation layer is provided below the phase change material layer. The ventilation layer has an air inlet and an air outlet, thereby exchanging gases with the outside environment.
[0008] The above technical solution involves setting a phase change material layer under the photovoltaic panel to absorb the heat of the photovoltaic panel, thereby regulating the temperature of the photovoltaic panel and preventing the photovoltaic panel from becoming less efficient due to excessive temperature. A ventilation layer is also set under the phase change material layer to exhaust the heat passing through the phase change material layer and prevent heat from entering the house.
[0009] Furthermore, the air outlet is located below the air inlet. This technical solution configures the ventilation layer as a thermo-pressure ventilation structure, allowing hot air within the ventilation layer to flow upwards and exit from the upper air outlet, thus completing gas exchange and achieving cooling.
[0010] Furthermore, an insulation layer is provided between the photovoltaic panel and the phase change material layer. The insulation layer can insulate some of the heat passing through the photovoltaic panel.
[0011] Furthermore, the phase change material layer is made of organic phase change materials. These organic phase change materials mainly include paraffin wax, ester acids, and polyols, typically possessing low melting points and high latent heats. Compared to inorganic phase change materials, organic phase change materials offer advantages such as low supercooling, uniform melting, self-nucleation, high compatibility with many materials, no stratification, stable chemical properties, safety and non-toxicity, and recyclability.
[0012] Furthermore, the phase change material layer is encapsulated in a high-polymer polyethylene box with a thickness of 2mm to 2.5mm. High-polymer polyethylene has good heat and cold resistance, making it suitable for both summer and winter.
[0013] Furthermore, the insulation layer uses polyurethane insulation board or extruded polystyrene insulation board. The insulation board has moisture-proof and waterproof properties, which can only isolate part of the heat from the photovoltaic panel and also serve a waterproof function.
[0014] Furthermore, the air inlet opens downwards, the air outlet opens upwards, and a cap is provided above the air outlet, with a gap between the cap and the air outlet. The downward-facing air inlet prevents rainwater from entering. The upward-facing air outlet facilitates the upward expulsion of hot air, while the cap at the air outlet further prevents rainwater from entering.
[0015] Furthermore, the ventilation layer includes at least four support members disposed between the phase change material layer and the roof. The support members include angle steel, with at least one angle steel provided at each of the four corners of the roof.
[0016] Based on the above technical solution, the beneficial effects of this utility model are as follows:
[0017] This application sets a phase change material layer under the photovoltaic panel to absorb the heat of the photovoltaic panel, so as to regulate the temperature of the photovoltaic panel and prevent the photovoltaic panel from becoming less efficient due to excessive temperature.
[0018] This application provides a ventilation layer below the phase change material layer. The ventilation layer can exchange air with the outside to dissipate the heat passing through the phase change material layer and prevent heat from entering the room.
[0019] To make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 This is a schematic diagram of the overall device structure of the photovoltaic phase change ventilated roof in this embodiment of the utility model;
[0022] Figure 2 This is a schematic diagram of the ventilation layer in an embodiment of this utility model.
[0023] The reference numerals in the above figures are as follows: 1. Photovoltaic panel; 2. Insulation layer; 3. Phase change material layer; 4. Ventilation layer; 41. Angle steel; 5. Roof. Detailed Implementation
[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0025] It should be noted that in the description of this utility model, the terms "first," "second," etc., are used only for descriptive purposes and to distinguish similar objects; there is no order between them, nor should they be construed as indicating or implying relative importance. Furthermore, in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0026] Example: Combining Figure 1-2 As shown, this embodiment discloses a photovoltaic phase change ventilated roof, comprising:
[0027] Photovoltaic panel 1, which is located on the outermost layer, is used for photoelectric conversion.
[0028] A thermal insulation layer 2 is installed below the photovoltaic panel 1, which can insulate some of the heat passing through the photovoltaic panel 1. The thermal insulation layer 2 is made of polyurethane insulation board. The polyurethane insulation board has moisture-proof and waterproof properties, which can both insulate some of the heat from the photovoltaic panel and play a waterproof role. Moreover, the rigid polyurethane formed after the addition of flame retardants is fireproof, flame-retardant, and high-temperature resistant, with a softening point of over 250 degrees Celsius, and it only decomposes at very high temperatures. When polyurethane burns, it forms ash on its foam surface, which helps to isolate the foam below and effectively prevents the spread of fire. In addition, polyurethane does not produce harmful gases at high temperatures. These characteristics make it more suitable as a building material with high safety requirements. In addition, polyurethane material has a closed-cell structure, which gives it good thermal insulation performance, freeze-thaw resistance, and sound absorption.
[0029] Optionally, the insulation layer 2 can also be made of extruded polystyrene insulation board. Extruded polystyrene insulation board has a dense surface layer and a closed-cell inner layer, resulting in a lower thermal conductivity and thus better thermal insulation performance. Furthermore, extruded polystyrene insulation board is lightweight and easier to install.
[0030] A phase change material layer 3 is disposed below the insulation layer 2. When the temperature rises to 37°C, the phase change material layer melts and absorbs heat to reduce the temperature of the photovoltaic panel 1 and prevent the photovoltaic panel 1 from reducing its working efficiency due to excessive temperature. When the temperature drops to 35°C, the phase change material layer releases heat and solidifies.
[0031] The phase change material layer 3 is made of organic phase change materials. These organic phase change materials mainly include paraffin wax, ester acids, and polyols, typically possessing low melting points and high latent heats. Compared to inorganic phase change materials, organic phase change materials offer advantages such as low supercooling, uniform melting, self-nucleation, high compatibility with many materials, no delamination, chemical stability, safety, non-toxicity, and recyclability. These advantages make them more suitable for rooftop working environments with temperatures ranging from 0℃ to 40℃.
[0032] The phase change material layer 3 is encapsulated in a 2.3mm thick high-polymer polyethylene box. High-polymer polyethylene is an opaque white, waxy material with a specific gravity of 0.941~0.960, and is soft and tough. High-polymer polyethylene is resistant to acids and alkalis, organic solvents, and has excellent electrical insulation properties. Combined with its melting point of 142℃ and decomposition temperature of 300℃, it is suitable for use in both summer and winter.
[0033] Optionally, the thickness of the polyethylene box can be selected from 2mm to 2.5mm.
[0034] A ventilation layer 4 is disposed below the phase change material layer 3. The ventilation layer 4 includes four angle steels 41, which are respectively disposed at the four corners of the roof. The ventilation layer 4 is in direct contact with the outside air in all four directions. When the wind pressure in any direction increases, the wind can enter the ventilation layer 4 through the openings in the corresponding direction and flow out of the ventilation layer 4 through the openings in other directions, thereby carrying away the heat in the ventilation layer 4. This is heat exchange under the action of wind pressure. In addition, when the heat from the phase change material layer 3 enters the ventilation layer 4, the air temperature in the ventilation layer 4 increases and the density decreases. The hot air rises and, after hitting the top of the ventilation layer 4, flows out through the openings on all four sides of the ventilation layer 4. At the same time, the cooler outside air enters the ventilation layer from the bottom of the openings, thereby realizing heat exchange under the action of thermal pressure.
[0035] Optionally, the ventilation layer 4 is constructed with a glass cavity. The ventilation layer 4 has an air outlet and an air inlet, with the air outlet located below the air inlet, forming a thermo-pressure ventilation structure. Hot air within the ventilation layer 4 flows upward and exits through the upper air outlet, completing gas exchange and achieving cooling. The air inlet opens downwards to prevent rainwater from entering. The air outlet opens upwards to facilitate the upward expulsion of hot air. A cap is provided above the air outlet, with a gap between the cap and the air outlet, preventing rainwater from entering through the air outlet.
[0036] Below the ventilation layer 4 is the roof 5.
[0037] In the photovoltaic phase change ventilated roof disclosed in this application, as the intensity of outdoor solar radiation gradually increases, the photovoltaic panel 1 begins photoelectric conversion, and its temperature rises, transferring heat into the building. The insulation layer 2 insulates against some of this heat. When the photovoltaic panel 1 transfers heat downwards, causing its temperature to reach 37°C, the phase change material layer 3 melts and absorbs heat to lower the operating temperature of the photovoltaic panel 1, thus ensuring its efficiency. Simultaneously, the ventilation layer 4 exchanges air with the outside under thermal pressure, dissipating the heat transferred by the phase change material layer 3 and preventing heat from entering the building. At night, when the ambient temperature drops to 35°C, the phase change material layer 3 releases heat and solidifies. The ventilation layer 4 simultaneously exchanges air with the outside to dissipate the heat released by the phase change material layer 3, accelerating its solidification and preventing heat from entering the building.
[0038] The ventilation layer 4 allows heat transferred from the upper layer to be discharged through thermal pressure, thereby preventing heat from entering the room and reducing the building energy consumption required for indoor cooling.
[0039] This utility model uses specific embodiments to illustrate the principle and implementation of the utility model. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of the utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of the utility model. Therefore, the content of this specification should not be construed as a limitation of the utility model.
Claims
1. A photovoltaic phase change ventilated roof characterized in that, The application relates to a photovoltaic panel, comprising: a photovoltaic panel for photoelectric conversion; a thermal insulation layer arranged below the photovoltaic panel, wherein the thermal insulation layer is made of polyurethane or extruded polystyrene; a phase change material layer arranged below the thermal insulation layer, wherein the phase change material layer can absorb heat when the temperature exceeds a first preset temperature and release heat when the temperature falls below a second preset temperature; a ventilation layer arranged below the phase change material layer, wherein the ventilation layer has an air inlet and an air outlet to exchange air with the outside, and the ventilation layer comprises at least four supporting members arranged between the phase change material layer and a roof, wherein the supporting members comprise angle steels, and each of the four corners of the roof is provided with at least one angle steel.
2. The photovoltaic phase change ventilated roof of claim 1, wherein, The air outlet is arranged below the air inlet.
3. The photovoltaic phase change ventilated roof of claim 1, wherein, The phase change material layer is made of organic phase change material.
4. The photovoltaic phase change ventilated roof of claim 3, wherein, The phase change material layer is packaged in a high-polyethylene box with a thickness of 2mm-2.5mm.
5. The photovoltaic phase change ventilated roof of claim 2, wherein, The air inlet is downwardly opened, the air outlet is upwardly opened, a cap is arranged above the air outlet, and a space is formed between the cap and the air outlet.