Solar Energy Utilization System

Abstract

A solar energy utilization system that enables efficient utilization of solar energy through the synergistic effect of a solar panel and a solar hot water heater. [Solution] The solar energy utilization system comprises a perovskite solar cell unit 12 that converts the light energy of sunlight into electrical energy, and a solar water heater heat collection plate 14 that is arranged below the perovskite solar cell unit 12 and collects heat obtained from the sunlight that has passed through the perovskite solar cell unit 12. The system also comprises a case body 20 for accommodating the perovskite solar cell unit 12 and the solar water heater heat collection plate 14, a tempered glass section 16 that is provided within the case body 20 and on which the perovskite solar cell unit 12 is placed, and a flow passage section 18 that is provided within the case body 20 and in contact with the solar water heater heat collection plate 14, for flowing a fluid to exchange the heat collected by the solar water heater heat collection plate 14.

Description

[Technical field]

[0001] The present invention relates to a solar energy utilization system. [Background technology]

[0002] Conventionally, as a technology using solar energy, a solar water heater and a photovoltaic power generation system are installed separately. For example, Patent Document 1, which is a technology related to the present invention, describes a water heater body having several heat exchange tubes and a hot water manifold to which these heat exchange tubes are connected, a frame fitted around the water heater body, a symmetrical first reflector and a second reflector provided on both sides of the frame, two heat insulating layers provided on the backs of the first reflector and the second reflector, respectively, two protective covers provided on the two heat insulating layers, two rotary actuators provided on both sides of the frame, respectively connecting the bottom ends of the first reflector and the second reflector, respectively driving the first reflector and the second reflector to rotate, and a control system for electrically connecting the two rotary actuators and controlling the two rotary actuators according to the direction of solar irradiation to rotate the first reflector and the second reflector. A synergistic effect solar water heater is disclosed, which includes a solar tracking controller that drives and rotates the reflector to form a light receiving reflecting surface angle and reflects the sunlight onto these heat exchange tubes, the internal water source flows through these heat exchange tubes and undergoes heat exchange, becomes hot water, and then collects it into the hot water manifold, and in the absence of sunlight, controls the two rotary drivers to simultaneously drive and rotate the first reflector and the second reflector, stacking them on the water heater main body and covering it, thereby serving as a laminated protective cover for the water heater main body.

[0003] Furthermore, Patent Document 2 discloses a solar panel-floor integrated hot water supply structure in which the floor of a normal solar water heater is formed by covering it with solar panels, and the upper water tank is formed from a transparent body such as glass, so that the water in the tank is heated by the heat absorption effect of the black color of the solar panel, while also generating electricity, which is its original function. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-57052 A [Patent Document 2] JP 2000-64946 A Summary of the Invention [Problem to be solved by the invention]

[0005] The above-mentioned Patent Documents 1 and 2 disclose a configuration in which a solar hot water heater and a solar cell are used in combination, but do not disclose a use in which a synergistic effect is produced by stacking the solar cell and the solar hot water heater.

[0006] An object of the present invention is to provide a solar energy utilization system that makes it possible to efficiently utilize solar energy by utilizing the synergistic effect of a solar cell and a solar hot water heater. [Means for solving the problem]

[0007] The solar energy utilization system according to the present invention comprises a perovskite solar cell unit that converts the light energy of sunlight into electrical energy, a solar water heater heat collection plate that is arranged below the perovskite solar cell unit and that collects heat obtained from the sunlight that has passed through the perovskite solar cell unit and is made of black aluminum, a case body for accommodating the perovskite solar cell unit and the solar water heater heat collection plate, and a case body for accommodating the perovskite solar cell unit and the solar water heater heat collection plate. ,beforeThe solar water heater comprises an air layer provided between a reinforced glass part on which the perovskite solar cell part is placed and the solar water heater heat collection plate, and a flow passage part provided within the case body so as to be in contact with the solar water heater heat collection plate and for flowing a fluid to exchange heat collected by the solar water heater heat collection plate, wherein the flow passage part is a flow path that is spread throughout the entire area of ​​the solar water heater heat collection plate and has a large pipe that functions as an aorta and extends from left to right in a plan view, a medium pipe that extends vertically and horizontally to form a large mesh lattice, and small pipes that extend vertically and horizontally to form a small mesh lattice, and the fluid flowing through the large pipe, the medium pipe, and the small pipe is oil. Effect of the Invention

[0011] According to the present invention, solar energy can be efficiently utilized by the synergistic effect of the solar cell and the solar hot water heater. [Brief description of the drawings]

[0012] [Figure 1] 1 is a diagram showing a solar energy utilization system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing a case body that houses a perovskite solar cell unit and a heat collection plate for a solar hot water heater of an embodiment of a solar energy utilization system according to the present invention. [Diagram 3] FIG. 1 is a diagram for explaining the advantage of using a perovskite solar cell unit in a solar energy utilization system according to an embodiment of the present invention. [Figure 4] FIG. 1 is a diagram for explaining the advantage of using a perovskite solar cell unit in a solar energy utilization system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following, the same elements in all the drawings are given the same reference numerals, and duplicated explanations will be omitted. In addition, in the explanation in the text, the reference numerals previously described will be used as necessary.

[0014] Fig. 1 is a diagram showing a solar energy utilization system 10 according to an embodiment of the present invention. Fig. 2 is a diagram showing a case body 20 that houses a perovskite solar cell unit 12 and a solar hot water heater heat collecting plate 14 of the solar energy utilization system 10 according to the embodiment of the present invention.

[0015] 3 and 4 are diagrams for explaining the advantages of using the perovskite solar cell unit 12 in the solar energy utilization system 10 according to the embodiment of the present invention.

[0016] The solar energy utilization system 10 is a system that utilizes solar energy to obtain thermal energy and electrical energy. The solar energy utilization system 10 includes a perovskite solar cell unit 12 that converts the light energy of sunlight into electrical energy, a solar hot water heater heat collector plate 14 that collects the heat of sunlight, a tempered glass unit 16, a flow passage unit 18, a case body 20, a heat pump 22, a heat-retaining hot water tank 24, a connection box 26, a power conditioner 28, a distribution board 30, and a storage battery 32.

[0017] In the perovskite solar cell section 12, perovskite crystals on the substrate absorb light and generate electricity. The perovskite solar cell section 12 has a structure in which thin films are layered, and is made by applying materials to the substrate like paint, so low-cost substrates such as films can be used. As the substrate is a film, it has the advantage of being light and bendable.

[0018] The perovskite solar cell section 12 has a perovskite layer in the center that absorbs light and generates positive and negative charges. The perovskite layer is sandwiched between a hole transport layer that extracts positive charges and an electron transport layer that extracts negative charges, and is further sandwiched between two electrodes.

[0019] The perovskite solar cell unit 12 can be bent or folded, making it possible to accommodate a variety of shapes. Its manufacturing costs are expected to be around 1 / 3 to 1 / 5 of those of silicon-type solar power generation, and it has high energy conversion efficiency and can generate electricity even with weak light.

[0020] As shown in Figure 3(b), the perovskite solar cell unit 12 absorbs sunlight in the visible light range (380 to 780 nm) and absorbs almost no sunlight in the infrared range. Conventional silicon solar panels absorb sunlight in the infrared range as well, making it difficult to absorb it as solar heat, but the perovskite solar cell unit 12 allows sunlight in the infrared range to pass through.

[0021] The perovskite solar cell unit 12 efficiently absorbs sunlight in the visible light range (380 to 780 nm), making it possible to generate power even on cloudy or rainy days. Figure 4 shows a comparison of power generation in Tokyo under various weather conditions over the course of a day using perovskite solar cells and conventional silicon solar cells.

[0022] On a normal sunny day as shown in Figure 4(a), conventional silicon-type solar power generation generates more electricity, but on a cloudy or rainy day as shown in Figure 4(b), the perovskite solar cell unit 12 generates about three times more electricity than conventional silicon-type solar power generation. Comparing the weather over the course of a year, there is data that shows that the total amount of electricity generated throughout the year does not change much, since the number of sunny days and non-sunny days (cloudy and rainy days) is half and half.

[0023] The solar hot water heater heat collecting plate 14 is disposed below the perovskite solar cell section 12 and has the function of collecting heat obtained from sunlight that has passed through the perovskite solar cell section 12.

[0024] The solar hot water heater heat collecting plate 14 is preferably made of a black aluminum plate. Aluminum has a specific heat (J / kg°C) of 900, a thermal conductivity (W / mK) of 204, a melting point (°C) of 660.2, and a specific gravity (g) of 2.70.

[0025] For comparison, iron has a specific heat (J / kg℃) of 444, a thermal conductivity (W / mK) of 80, a melting point (℃) of 1538, and a specific gravity (g) of 7.87, while zinc has a specific heat (J / kg℃) of 383, a thermal conductivity (W / mK) of 113, a melting point (℃) of 419.46, and a specific gravity (g) of 7.14.

[0026] Copper has a specific heat (J / kg℃) of 419, a thermal conductivity (W / mK) of 372, a melting point (℃) of 1083, and a specific gravity (g) of 8.93, while magnesium has a specific heat (J / kg℃) of 1013, a thermal conductivity (W / mK) of 54, a melting point (℃) of 650, and a specific gravity (g) of 1.74.

[0027] Stainless steel has a specific heat (J / kg℃) of 460, a thermal conductivity (W / mK) of 16, a melting point (℃) of 1400, and a specific gravity (g) of 7.70, while water (20℃) has a specific heat (J / kg℃) of 4182, a thermal conductivity (W / mK) of 0.602, a melting point (℃) of 0, and a specific gravity (g) of 1.0. Considering these, aluminum has high thermal conductivity, is light in weight, and is low cost, making it ideal for use as a heat collector.

[0028] The tempered glass section 16 is glass on which the perovskite solar cell section 12 is placed. The tempered glass section 16 is made by subjecting normal glass (float glass) to heat treatment and then rapidly cooling it, and has wind pressure resistance approximately 3.5 to 4 times that of float glass. It looks exactly the same as float glass and is indistinguishable from it. Another characteristic is that while normal glass breaks sharply like a blade, the tempered glass section 16 shatters into pieces.

[0029] The flow passage portion 18 is in contact with the solar water heater heat collection plate 14, which is installed via the air layer 13 provided between the flow passage portion 18 and the tempered glass portion 16, and is a flow path for flowing a fluid to exchange heat collected by the solar water heater heat collection plate 14. The air layer 13 is provided in order to prevent the tempered glass portion 16 from taking away the heat collected by the solar water heater heat collection plate 14.

[0030] Industrial oil flows through the flow passage 18. The industrial oil has a specific heat (J / kg°C) of 1796, a thermal conductivity (W / mK) of 0.148, and a coefficient of expansion (×10 -3 / ℃) is 0.70 and the specific gravity (g) is 0.8 to 0.9.

[0031] The specific heat, thermal conductivity, expansion coefficient, and specific gravity of water vary depending on the temperature: 0°C, 20°C, 80°C, and 100°C. At 0°C, the specific heat (J / kg°C) is 4217, the thermal conductivity (W / mK) is 0.569, and the expansion coefficient (×10 -3 / ℃) is -0.06, and the specific gravity (g) is 1.0. The specific heat (J / kg℃) at 20℃ is 4182, the thermal conductivity (W / mK) is 0.602, and the expansion coefficient (×10 -3 / ℃) is 0.65 and the specific gravity (g) is 1.0.

[0032] The specific heat at 80°C (J / kg°C) is 4196, the thermal conductivity (W / mK) is 0.672, and the expansion coefficient (×10 -3 / ℃) is 0.65, and the specific gravity (g) is 1.0. The specific heat at 100℃ (J / kg℃) is 4215, the thermal conductivity (W / mK) is 0.682, and the expansion coefficient (×10 -3 / ℃) is 0.78 and its specific gravity (g) is 1.0. Thus, the specific heat of oil is less than half that of water, so it absorbs heat faster and is lighter in weight than water.

[0033] As shown in Figure 2, the flow passage section 18 is provided with a large pipe 18a that functions as an aorta in a plan view and extends from left to right to cover substantially the entire area of ​​the solar heat collecting plate 14, a medium pipe 18b that extends vertically and horizontally to form a large mesh lattice, and small pipes 18c that extend vertically and horizontally to form a small mesh lattice.

[0034] The flow passage portion 18 may be made of any material having an appropriate strength, for example, a mixture of magnesium, zinc, and aluminum, but may of course be made of other materials.

[0035] The case body 20 is a case that houses the perovskite solar cell section 12, the air layer 13, the solar hot water heater heat collecting plate 14, the tempered glass section 16, and the flow passage section 18.

[0036] The case body 20 has a tray-like shape with an open top. As shown in the cross-sectional view of Fig. 2(b), the strengthened glass part 16 and the solar water heater heat collection plate 14 are directly fixed to the case body 20. The perovskite solar cell part 12 is placed and attached to the front surface (upper surface) of the strengthened glass part 16, and the flow passage part 18 is attached to the back surface (lower surface) of the solar water heater heat collection plate 14 so as to be in contact with it.

[0037] The case body 20 is preferably made of a material having an appropriate strength, and can be made of, for example, a composite plate of aluminum and polyethylene resin, but of course it may be made of other materials.

[0038] The heat pump 22 includes a compressor that compresses the refrigerant and turns it into a high-temperature, high-pressure gas, a condenser where the compressed refrigerant releases heat and turns into a liquid, an expansion valve that rapidly expands the refrigerant to reduce its temperature and pressure, and an evaporator where the refrigerant absorbs the surrounding heat and turns back into a gas.

[0039] In the heat pump 22, heat can be transferred efficiently by repeating the following steps: an evaporation process in which the refrigerant absorbs surrounding heat in the evaporator and changes from liquid to gas; a compression process in which the gaseous refrigerant is compressed in the compressor to become a high-temperature, high-pressure gas; a condensation process in which the high-temperature, high-pressure gas releases heat in the condenser and changes to liquid; and an expansion process in which the liquid refrigerant passes through an expansion valve and rapidly expands to a low-temperature, low-pressure state.

[0040] The heat-retaining hot water tank 24 is a tank for storing hot water heated by the heat pump 22. The heat-retaining hot water tank 24 can be made of stainless steel (e.g., SUS444) or a resin-lined steel plate. This makes it resistant to corrosion and allows the supply of clean hot water.

[0041] Here, a configuration including the solar hot water heater heat collecting plate 14, the flow passage portion 18, the heat pump 22, and the heat-retaining hot water tank 22 is called a solar hot water heater 6.

[0042] The junction box 26 is one of the important components of the solar power generation system, and is a device for connecting the perovskite solar cell unit 12 and the power conditioner 28. The junction box 26 collects the DC power generated by the perovskite solar cell unit 12 and sends it to the power conditioner 28. This converts the DC power into AC power.

[0043] The junction box 26 has a function of adjusting voltage variations when combining the power from multiple perovskite solar cell units 12. The junction box 26 incorporates safety devices such as switches and lightning protection elements, and has the functions of controlling the flow of electricity and protecting equipment from lightning strikes.

[0044] The power conditioner 28 automatically finds the combination of voltage and current that maximizes the amount of power generated by the perovskite solar cell unit 12, supporting efficient power generation. The power conditioner 28 has a function to transmit power at an appropriate voltage when the generated power is sold to the power company. This prevents the backflow of power and realizes a stable power supply. The power conditioner 28 has a function to prevent accidents by cutting off the output in the event of a power outage or abnormality. This allows the solar power generation system to be operated safely.

[0045] The distribution board 30 has the function of distributing electricity generated by the perovskite solar cell unit 12 and electricity supplied by the power company to each device and room in the home. The distribution board 30 has a built-in breaker that detects leakage or overcurrent and cuts off the electricity, preventing fires and electric shock accidents. The distribution board 30 has the function of reversing the flow of electricity when surplus electricity from the perovskite solar cell unit 12 is sold to the power company. This allows the generated electricity to be used efficiently.

[0046] The storage battery 32 stores the electricity generated by the perovskite solar cell unit 12, making it possible to use the electricity during times when solar power generation is not possible, such as at night or on cloudy days. The storage battery 32 plays a role in stabilizing the supply of electricity, making it possible to provide a stable power supply even in areas where the power supply is unstable.

[0047] The storage battery 32 stores the power generated by the perovskite solar cell unit 12, thereby reducing the amount of power purchased from the power company and saving on electricity bills. The storage battery 32 can supply power for a certain period of time by using the stored power during a power outage.

[0048] The storage battery 32 may be, for example, a lithium ion secondary battery, but may of course be another secondary battery, for example, a nickel-metal hydride storage battery.

[0049] Here, a configuration including the perovskite solar cell unit 12, the strengthened glass unit 16, the junction box 26, the power conditioner 28, the distribution board 30 and the storage battery 32 is referred to as a solar power generation system 8.

[0050] Next, the operation of the solar energy utilization system 10 configured as described above will be described. First, a comparison will be made between silicon-type solar power generation and the perovskite solar cell unit 12. As shown in Fig. 3(b), the perovskite solar cell unit 12 efficiently absorbs sunlight in the visible light region (380 to 780 nm), making it possible to generate power even on cloudy or rainy days.

[0051] Figure 4 compares the power generation in Tokyo in various weather conditions for the perovskite solar cell unit 12 and conventional silicon solar power generation. As mentioned above, on normal sunny days, conventional silicon solar power generation generates more power, but on cloudy or rainy days, the perovskite solar cell unit 12 generates about three times more power than the conventional type. Comparing the weather over the course of a year, the number of sunny days and non-sunny days (cloudy or rainy days) is roughly half and half, so the total amount of power generation throughout the year does not change much.

[0052] Fig. 3 is a diagram showing the relationship between the wavelength and spectrum of light absorbed by conventional silicon-type photovoltaic power generation. As described above, as shown in Fig. 3(a) and Fig. 3(c), silicon-type photovoltaic power generation absorbs not only visible light of 380 to 780 nm but also infrared light.

[0053] As described above, the perovskite solar cell unit 12 absorbs sunlight in the visible light range (380 to 780 nm) and barely absorbs any in the infrared range. Conventional silicon-type solar cell power generation absorbs sunlight in the infrared range as well, making it difficult to absorb it as solar heat.

[0054] In contrast, in the solar energy utilization system 10 according to an embodiment of the present invention, the perovskite solar cell section 12 allows solar energy in the infrared region to pass through, so that the solar hot water heater heat collection plate 14 can efficiently absorb thermal energy, making it possible to absorb approximately six times the amount of heat compared to silicon-type solar power generation.

[0055] In general, the solar hot water heater 6 supplies heat energy, is used for hot water supply and heating, has an energy efficiency of 40 to 60%, and is applicable to buildings with a high demand for hot water supply, such as hospitals, hotels, welfare facilities, and schools. The supply energy per unit area is 600 kW / m 2 In contrast, the solar power generation system 8 supplies electricity as energy, is used for electrical appliances and to sell electricity to power companies, has an energy efficiency of 7 to 18%, can be installed in a variety of buildings, and can supply energy per unit area of ​​130 kW / m 2 It is.

[0056] Thus, the energy efficiency of the solar hot water heater 6 is better than that of the photovoltaic power generation system 8, but conventionally, vacuum tubes were necessary to prevent the heat obtained from sunlight from being dissipated. However, vacuum tubes have the problem that they are expensive and fragile and weak. Furthermore, conventional solar hot water heaters use water, which causes durability problems and problems with excessive weight (200 to 400 kg). In addition, because water is used, even if antifreeze is added, the water freezes in cold regions in winter, which is another issue, making it impossible to install them in cold regions.

[0057] The solar energy utilization system 10 according to the embodiment of the present invention has a remarkable effect on such problems. Specifically, by replacing water with oil, there is no problem with rust, and since oil does not freeze (approximately -60°C), it can be used in cold regions, and since only a small amount of oil is circulated, the problem of excess weight is also solved (weight: approximately 20 to 50 kg).

[0058] In the solar energy utilization system 10, the circulating oil flows through the large pipes 18a, then through the medium pipes 18b that form a large mesh, and also through the small pipes 18c that form a fine mesh, so that it spreads over the area on the back side of the heat collecting plate 14 for the solar hot water heater, as shown in Fig. 2. As a result, there is almost no problem with heat dissipation because the oil circulates within the equipment, and the heat pump 22 has good thermal efficiency even at low temperatures, so a constant high temperature hot water can be maintained in the insulated hot water tank 24.

[0059] In this way, solar water heaters using oil are highly efficient at using energy from sunlight. The heat conversion efficiency is about 40-60%. In the case of water, the pipes deteriorate due to rust and limescale, so the durability is about 10 years, but oil is resistant to corrosion such as rust and has a durability of about 20-30 years.

[0060] In cold regions, water freezes (at about 0°C), but oil (at about -60°C) has little risk of freezing. The specific heat of oil is about half that of water, so it absorbs heat faster and circulates with good heat exchange efficiency even at low temperatures in the heat pump 22.

[0061] Water expands at high temperatures (approximately 100°C), but oil (approximately 400°C) does not expand due to heat, so there is less risk of accidents. Even with a small amount of oil, it circulates through the solar hot water heater 6 with efficient heat exchange, so the total weight of the equipment when installed on the roof is lighter.

[0062] As described above, according to the solar energy utilization system 10, the perovskite solar cell unit 12 can generate more power from sunlight in the visible light range (380 to 780 nm) than conventional silicon-type solar power generation, and since it can pass infrared light, heat can be obtained at the solar hot water heater heat collector plate 14, which has the advantage of being able to absorb approximately six times the amount of heat compared to conventional silicon-type solar power generation.

[0063] Furthermore, the solar hot water heater 6 heats water absorbed by the heat pump 22 and sends it to the heat-retaining hot water tank 24 for storage. This stored hot water is used for hot water supply, hot water floor heating, boiling water for the bath, etc. Furthermore, the electricity generated in the perovskite solar cell unit 12 is transmitted to a power conditioner 28 and a distribution board 30, and is sent to domestic electrical products and a storage battery 32.

[0064] The components of the solar energy utilization system 10 are merely examples and can be changed as appropriate. For example, the solar hot water heater 6 is described as using the heat pump 22, but a normal heat exchanger may be used. [Explanation of symbols]

[0065] 6 Solar water heater, 8 Photovoltaic power generation system, 10 Solar energy utilization system, 12 Perovskite solar cell section, 13 Air layer, 14 Heat collector plate for solar water heater, 16 Reinforced glass section, 18 Flow passage section, 18a Large pipe, 18b Medium pipe, 18c Small pipe, 20 Case body, 22 Heat pump, 24 Insulated hot water tank, 26 Connection box, 28 Power conditioner, 30 Distribution board, 32 Storage battery.

Claims

[Claim 1] a perovskite solar cell unit that converts light energy of sunlight into electrical energy; a solar water heater heat collection plate made of black aluminum, which is disposed below the perovskite solar cell unit and collects heat obtained from the sunlight that has passed through the perovskite solar cell unit; A case body for accommodating the perovskite solar cell unit and the solar water heater heat collection plate; an air layer provided within the case body between a reinforced glass portion on which the perovskite solar cell portion is mounted and the solar water heater heat collecting plate; a flow passage portion provided in the case body so as to be in contact with the heat collection plate for the solar water heater, for allowing a fluid to flow in order to exchange heat collected by the heat collection plate for the solar water heater; Equipped with The flow passage portion is a flow path that is spread throughout the entire area of ​​the heat collecting plate for the solar hot water heater, and has a large pipe that functions as an aorta and extends from side to side in a plan view, a medium pipe that extends vertically and horizontally to form a large mesh lattice, and a small pipe that extends vertically and horizontally to form a small mesh lattice, A solar energy utilization system, characterized in that the fluid flowing through the large pipe, the medium pipe, and the small pipe is oil.

Images