JP6040511B2 - Solar power system - Google Patents

Description

  The present invention relates to a novel sunlight utilization system. More specifically, the solar light utilization system of the present invention relates to improvement of a system that decomposes water using a photo-semiconductor catalyst activated by sunlight and uses the obtained hydrogen and oxygen for a fuel cell reaction or the like.

An optical semiconductor catalyst that decomposes water by using the energy of sunlight is known (see Patent Document 1). If this photo-semiconductor catalyst is used, water can be decomposed with small electric power, and as a result of decomposing water, hydrogen and oxygen with high purity can be obtained.
Patent Documents 2 and 3 disclose a system that supplies hydrogen obtained by decomposing water using sunlight to a fuel cell.

JP 2006-299368 A JP 2000-144464 A Japanese Unexamined Patent Publication No. 2000-333481

Examples of the solar light utilization system include titanium dioxide (TiO2), iron oxide (Fe2O3), niobium oxide (Nb2O5), strontium titanate (SrTiO3), barium titanate (BaTiO3), tungsten oxide (WO3), and bismuth vanadium. There is a technique using an electrode having a semiconductor such as an oxide (BiVO4) (hereinafter also referred to as a photoelectrode) and using a technique for decomposing water (for example, see Patent Document 2 and Patent Document 3).
As in the above-described solar light utilization system, attention has been paid to hydrogen obtained by the decomposition of water, and a technique for attempting to utilize it in a fuel cell has been proposed. However, focusing on the oxygen obtained from the decomposition of water, it is not sufficient to study how to use this efficiently, and the use of hydrogen and oxygen is still much studied and improved. It is thought that there is room for

  Therefore, an object of the present invention is to provide a system for more efficiently utilizing hydrogen and oxygen obtained by a sunlight utilization system that performs water splitting using a photoelectrode having a photosemiconductor catalyst.

The solar light utilization system according to the first aspect of the present invention has a pair of electrodes carrying a photo-semiconductor catalyst on one side, and decomposes the electrolytic solution using solar energy irradiated on the photo-semiconductor catalyst. A water splitting unit;
And a gas supply unit having a path for supplying hydrogen and oxygen generated by the decomposition of the electrolytic solution to a plurality of gas utilization devices using at least one of them. And
The gas supply unit is a solar power utilization system that distributes the amount of hydrogen and oxygen supplied to the plurality of gas utilization devices according to the required amount of hydrogen and oxygen of each of the plurality of gas utilization devices. is there.

  According to such a configuration, not only a power generator such as a fuel cell and a gas turbine generator, but also a plurality of gas using devices including gas appliances and air conditioners as existing home infrastructure, the hydrogen required by them. In addition, hydrogen and oxygen are distributed and supplied according to the amount of oxygen. Thereby, according to the energy needs in a user's life, hydrogen and oxygen can be efficiently utilized simultaneously with several gas utilization apparatus.

According to a second aspect of the present invention, the gas utilization device includes a power generation device having an exhaust heat recovery mechanism,
The gas supply unit has a path for supplying air to the power generation device, and the amount of oxygen and air to be supplied to the power generation device in accordance with a required amount of exhaust heat recovery of the power generation device. Adjust.
According to this, for example, when the amount of exhaust heat recovery required by the power generation device is large, the exhaust gas loss is intended by adjusting the amount of oxygen supplied to the power generation device to be reduced and the amount of air to be increased. Therefore, the amount of exhaust heat recovered from the exhaust gas can be increased.

According to the third aspect of the present invention, the gas supply unit sets the distribution amount of hydrogen and oxygen for each of the plurality of gas utilization devices to a priority that can be arbitrarily set between the plurality of gas utilization devices. Adjust accordingly.
According to this, hydrogen and oxygen can be efficiently utilized in a mode desired by the user or in a mode more suitable for the user's life.

According to a fourth aspect of the present invention, the solar light utilization system includes a daily illuminance measurement unit that measures the daily illuminance for the electrode,
The gas supply unit has a path for supplying gas fuel from the outside to the gas utilization device,
The gas supply unit adjusts the amount of gas fuel supplied from the outside to the gas utilization device according to the daily illuminance measured by the daily illuminance measurement unit.
According to this, when the amount of hydrogen generated in the water splitting unit is low and the amount of hydrogen generated in the water splitting unit is less than the amount required by the gas utilization device, the external gas fuel is complementarily supplied to the gas utilization device. Can be supplied.

According to a fifth aspect of the present invention, the plurality of gas utilization devices include an air conditioner,
The gas supply unit supplies oxygen generated by the decomposition of the electrolytic solution to the air conditioner so as to be mixed into the conditioned air of the air conditioner.
According to this, it becomes possible to contribute to a user's fatigue recovery by releasing air with high oxygen concentration from an air conditioner. Thus, not only the hydrogen produced | generated by the sunlight utilization system but utilization with oxygen alone can also be aimed at.

FIG. 1 is a block diagram showing a configuration of a sunlight utilization system according to an embodiment of the present invention. FIG. 2 is a flowchart showing the amount of water control in the example. FIG. 3 is a block diagram illustrating the configuration of the gas distribution control unit and the gas utilization device according to the embodiment. FIG. 4 is a flowchart showing the gas distribution control of the embodiment.

  In the above, the photo-semiconductor catalyst refers to a catalyst capable of decomposing water into hydrogen and oxygen by using solar energy and adding a small electric power assist thereto. Examples of such semiconductor materials include TiO2 (titanium dioxide), Fe2O3 (iron oxide), Nb2O5 (niobium oxide), SrTiO3 (strontium titanate), BaTiO3 (barium titanate), ZrO (zinc oxide), SnO2 (tin dioxide), Examples thereof include cadmium sulfide (CdS), WO3 (tungsten oxide), BiVO4 (bismuth vanadium oxide), and the like. When such a catalyst is attached to one of a pair of electrodes, immersed in an electrolytic solution, a predetermined voltage is applied to the electrodes and sunlight is irradiated, moisture in the electrolytic solution is electrolyzed on the surface of the catalyst. The externally applied voltage is appropriately set depending on the catalyst. This voltage can be supplied from the fuel cell. Of course, an external power source such as a battery, a solar cell, or a system power source can also be used. The electrolyte and the concentration of the electrolyte can be arbitrarily selected according to the type of semiconductor, the application of the system, and the like.

  As the fuel cell, a known type of fuel cell such as a solid polymer electrolyte type or a solid oxide type can be used. Hydrogen obtained in the water splitting section is supplied to the hydrogen electrode of the fuel cell. The hydrogen obtained in the water splitting part is temporarily stored in a hydrogen storage part made of a hydrogen storage alloy or the like, and the pressure is adjusted and supplied to the hydrogen electrode. Oxygen obtained in the water splitting unit can also be temporarily stored in the oxygen storage unit and mixed with the air supplied to the air electrode of the fuel cell. By controlling the amount of oxygen in the air sent to the air electrode, the output characteristics of the fuel cell can be controlled.

  The produced water generated by the fuel cell reaction is collected in the fuel cell and appropriately added to the electrolytic solution in the water splitting section. An electrolytic solution circulation path is provided between the water splitting unit and the fuel cell, and the electrolytic solution is circulated in the circulation path, and water generated in the fuel cell is continuously or intermittently added to the circulation path. It is possible to supplement the decrease in water content of the electrolytic solution accompanying water decomposition.

Examples of the present invention will be described below. FIG. 1 is a block diagram illustrating a configuration of a solar light utilization system 1 according to the embodiment. The solar light utilization system 1 includes a water splitting module 3, a fuel cell 20, a heat exchanger 21, and a control circuit 80.
The water splitting module 3 is formed by connecting a plurality of unit cells of the water splitting device. The unit cell of the water splitting apparatus includes an electrode carrying the above-described oxide semiconductor catalyst made of an oxide and an electrolytic cell that is airtight and can transmit sunlight, and the electrode is immersed in the electrolytic cell. As the electrolytic solution, an alkaline (for example, sodium hydroxide), acid (for example, dilute sulfuric acid) or neutral (for example, carbonate) electrolytic solution is used. An external power supply 81 (system power supply, solar cell, battery, etc.) is connected to the electrode, and a voltage of 1.23 V or less is applied. The fuel cell 20 may be used instead of the external power source 81.

  In this example, each unit cell is provided with a daily illuminance meter 60, and the flow rate of the electrolyte can be controlled in units of cells according to the measured daily illuminance. Adjustment of the flow rate of the electrolytic solution is performed by the control device 80 controlling the opening degree of the flow rate control valves V10, V12, V14. A water level gauge 50 is attached to the water splitting module 3.

A hydrogen line 4, an oxygen line 6, and a circulation line 40 are drawn from the water splitting module 3. Hydrogen gas and oxygen gas obtained by water decomposition in the water splitting module 3 are separated and sent to the hydrogen line 4 and the oxygen line 6, respectively.
The hydrogen fed to the hydrogen line 4 is dehumidified by the dehumidifying film 5 and then accumulated in the hydrogen pressure vessel 31. A pressure gauge 35 is attached to the hydrogen pressure vessel 31. A hydrogen container 32 detachable in parallel with the hydrogen pressure container 31 is provided. For example, when the hydrogen pressure vessel 31 is full, the valve V16 is opened and the hydrogen gas in the hydrogen gas line 4 is stored in the vessel 32. The detachable hydrogen container 32 can be used as a hydrogen gas source for, for example, a fuel cell vehicle, a motorcycle, or a portable generator. Storage of hydrogen in the hydrogen pressure vessel 31 and the hydrogen vessel 32 may be storage in a gas state, storage by a hydrogen storage alloy, storage as a hydrogen compound by an organic hydride, or the like.

  The hydrogen line 4 on the outlet side of the hydrogen pressure vessel 31 is connected to a gas distribution control unit 71. Thereby, the hydrogen in the hydrogen pressure vessel 31 is supplied to the gas distribution control unit 71. A safety valve V <b> 20 is provided in the hydrogen line 4 between the hydrogen pressure vessel 31 and the gas distribution control unit 71. The safety valve V20 opens to release hydrogen when the pressure in the hydrogen pressure vessel 31 becomes a predetermined value or more.

  The oxygen line 6 is provided with a dehumidifying film 7. The oxygen line 6 is connected to the oxygen pressure vessel 33, and oxygen in the oxygen line 6 is stored in the oxygen pressure vessel 33. A pressure gauge 36 is attached to the oxygen pressure vessel 33. The oxygen line 6 on the outlet side of the oxygen pressure vessel 33 is connected to the gas distribution control unit 71. Thereby, oxygen in the oxygen pressure vessel 33 is supplied to the gas distribution control unit 71. A safety valve V24 is provided in the oxygen line 6 between the oxygen pressure vessel 33 and the gas distribution control unit 71. The safety valve V24 opens to release oxygen when the pressure in the oxygen pressure vessel 33 exceeds a predetermined value.

  The hydrogen line 4 and the oxygen line 6 further extending from the gas distribution control unit 71 are connected to the fuel cell 20 and are used to supply hydrogen and oxygen to the fuel cell 20, respectively. Further, an air supply line 30 extends from the gas distribution control unit 71 and is connected to the fuel cell 20 to supply air to the fuel cell 20. Furthermore, another hydrogen line 4 and oxygen line 6 are drawn out from the gas distribution control unit 71 and connected to gas utilization equipment 70 (home electrical equipment, gas equipment, etc. using at least one of hydrogen and oxygen), respectively. Used to supply hydrogen and oxygen to the gas utilization device 70. Further, the gas distribution control unit 71 is connected with the city gas reforming line 35 and the city gas line 36, respectively, so that the gas distribution control unit 71 receives supply of city gas reformed gas and city gas as external gas fuel. be able to.

  In this system 1, the electrolytic solution is circulated between the heat exchanger 21 and the water splitting module 3 via the circulation line 40. The circulating electrolyte can be supplied independently to each unit cell. Further, the circulation line 40 collects the generated water generated in the fuel cell 20 and supplies it to the water splitting module 3 by mixing it with the electrolyte. Thereby, in the water decomposition module 3, the water fall of the electrolyte solution accompanying the electrolysis of water can be supplemented.

  In the middle of the circulation line 40, a circulation pump 41, a valve V30, a filter 45, and a pressure sensor 47 are installed. Furthermore, an electrolytic solution concentration sensor (pH sensor) 42, an electrolytic solution reserve tank 43, and a water supply unit 44 as an external water source are connected to the circulation line 40. The circulation line 40 and the electrolyte reserve tank 43 are connected via a valve V32. The electrolyte reserve tank 43 is provided with a water level gauge 48 for measuring the electrolyte water level. The water supply unit 44 is connected to the circulation line 40 via a valve V34 (hydrolysis valve).

  The fuel cell 20 may be a solid polymer type or a solid oxide type. The air supply line 30 from the gas distribution control unit 71 is provided with a fan 15 and thermometers 17 and 18. The output power of the fuel cell 20 is sold through the DC / AC converter 23 and supplied to the gas utilization device 70. Further, as described above, the power of the fuel cell 20 can be supplied to the water splitting module 3. When there is no need for storage as hydrogen heat or storage as hydrogen, it is possible to provide an energy system in which electricity can be supplied directly from a solar cell power source joined in tandem to the back of the water splitting module 3 through a switching device. The fuel cell 20 has a discharge line 78 from the hydrogen electrode side.

  The generated water accumulated in the generated water drain 25 of the fuel cell 20 is supplied to the circulation line 40 via the water supply line 26. Reference sign V36 is a check valve. In this example, the generated water is sucked into the flow of the electrolytic solution in the circulation line 40, but the generated water may be sent into the circulation line 40 by a pump.

  The heat exchanger 21 has a structure that can take in the exhaust heat of the water splitting module 3 and the fuel cell 20. A circulation line 75 for circulating a heat medium such as water is provided between the fuel cell 20 and the heat exchanger 21, and the circulation of the heat medium is controlled by a pump 76 and a valve V38. On the other hand, as described above, the heat exchanger 21 and the water splitting module 3 are connected by the circulation line 40 for the electrolyte. By passing the electrolytic solution through the heat exchanger 21, the temperature of the electrolytic solution can be controlled. Through the heat exchange, the heat exchanger 21 cools the fuel cell 20 and takes out heat accompanying the fuel cell reaction to the outside as hot water. The amount of exhaust heat from the fuel cell 20 depends on the external output voltage. The amount of heat exhausted from the water splitting module 3 depends on the amount of energy absorbed by infrared light. When heat exchange is not established, the circulation line 40 may be separated from the heat exchanger 21.

  The control circuit 80 calculates the amount of water consumed in the electrolytic solution and the amount of generated water that can be supplied to control the amount of water supplied from the water supply unit 44. The control device 80 controls the amount of power supplied to the gas utilization device 70 via the DC / AC converter 23 according to the electrical load of the gas utilization device 70.

Control of the amount of water added from the water supply unit 44 will be described based on the flowchart of FIG.
The water decomposition amount A in the water decomposition module 3 can be obtained from, for example, the pressure change in the hydrogen pressure vessel 31 and / or the oxygen pressure vessel 33 (that is, the generation amount of hydrogen and / or oxygen) (FIG. 2, step 101). (Refer to (S101)).
On the other hand, the amount of water accumulated in the drain 25 of the fuel cell 20 can be calculated as follows.
First, the amount Wfc of water generated by the fuel cell reaction is
Wfc = 9.34 × 10 ⁻⁸ × Pe / Vc [kg / sec].
Here, Pe: Output [W] Vc: Cell voltage.

On the other hand, in the fuel cell 20, moisture is taken away with the air exhaust. The carry-away amount Wa can be calculated based on the temperature / humidity of the air sent to the fuel cell 20, the temperature / humidity of the exhausted air, and the amount of air supplied.
Therefore, the amount of water accumulated in the drain 25 of the fuel cell 20 (that is, the amount of generated water that can be supplied) B is B = Wfc−Wa (step 103).
The fuel cell 20 may dry up depending on the operating conditions, and the amount of generated water accumulated in the drain 25 may be less than the amount of water consumed by the water splitting module 3.
Therefore, the control circuit 80 calculates the difference (C) between the amount A of water consumed in the water splitting module 3 and the amount B of generated water that can be supplied (step 105). The valve V34 is controlled (step 107) to supply water to the electrolyte from an external water source.

The operation of the control circuit 80 theoretically keeps the amount of the electrolyte constant.
In this embodiment, a water level meter 50 is provided in the water splitting module 3 to measure the water level in the electrolyte bath (step 109). The control circuit 80 compares the electrolyte level in the electrolyte bath with a predetermined threshold value (step 111), and when the electrolyte level falls outside the predetermined threshold range (step 111: NO), An alarm is activated as an abnormal situation such as water leakage has occurred (step 113).
It is also possible to control the valve V34 so that this water level becomes constant by feedback control based on the water level of the electrolytic cell. However, such control makes it difficult to grasp that an abnormal situation such as water leakage occurs in the system.
The circulation line 40 may be separated from the heat exchanger 21.

  Next, the gas distribution control unit 71 of the embodiment will be described with reference to FIG. As shown in FIG. 3, the gas distribution control unit 71 controls the hydrogen line 4, the oxygen line 6, the air supply line 30, the city gas reforming line 35, the city gas line 36, the valves V101 to V108, and these valves. And a control device 711. In the present embodiment, as the gas utilization device 70 using at least one of hydrogen and oxygen, the main purpose is to directly use heat by combustion of gas such as an air conditioner 702 and a gas range (gas cooker) or a water heater. An apparatus (hereinafter referred to as a gas combustion apparatus 703) will be described as an example. However, the gas utilization apparatus 70 is not limited to these, and a gas air conditioning facility or the like is also conceivable. The fuel cell 20 is also a kind of gas utilization device.

In the gas distribution control unit 71, a valve V <b> 101 is installed in the air supply line 30 connected to the fuel cell 20. The hydrogen line 4 is branched into two and connected to the fuel cell 20 and the gas combustion device 703, respectively. A valve V105 is installed between the branch point of the hydrogen line 4 and the fuel cell 20, and a valve V106 is installed between the branch point and the gas combustion device 703.
In the gas distribution control unit 71, the oxygen line 6 is branched into three and connected to the fuel cell 20, the air conditioner 702, and the gas combustion device 703. Valves V102, V103, and V104 are installed between the branch point of the oxygen line 6 and the fuel cell 20, the air conditioner 702, and the gas combustion device 703, respectively.
In the gas distribution control unit 71, the city gas reforming line 35 is connected to the hydrogen line 4 upstream from the branch point of the hydrogen line 4. The city gas line 36 is connected to the oxygen line 6 between the branch point of the oxygen line 6 and the gas combustion device 703.

  Next, the gas distribution control according to the embodiment will be described with reference to FIG. Normally, the opening degree of the valves V101 to V108 is controlled so as to maximize the power generation efficiency of the fuel cell 20 based on the amount of hydrogen that can be supplied from the hydrogen pressure vessel 31. The gas distribution control in FIG. 4 is executed by the control device 711 every time the operation mode described below is switched during operation of the solar light utilization system 1.

  When the flow of FIG. 4 is started, first, in step 201, the operation modes of the fuel cell 20 and the gas using device 70 are acquired. This operation mode is good as what a user inputs manually according to life needs. Alternatively, it may be automatically set according to the time zone, season, temperature, weather, and the like. Furthermore, the control device 711 may have a learning function, learn the user's preference regarding the operation mode, and automatically set the operation mode. In the example of FIG. 4, one of a hot water supply priority mode, a power generation priority mode, a fatigue recovery priority mode, and a gas combustion device priority mode can be selected. It is also possible not to select any mode.

  Next, the routine proceeds to step 203, where it is determined whether or not the hot water supply priority mode is selected. If it is determined that the hot water supply priority mode has been selected, the routine proceeds to step 205, where the opening degrees of the valves V101 and V105 are increased. Thus, the air supply amount to the fuel cell 20 is increased by increasing the opening degree of the valve V101. Thus, the exhaust gas loss of the fuel cell 20 is increased, thereby increasing the amount of hot water obtained by the heat exchanger 21. In order to maintain the power generation amount while increasing the exhaust gas loss of the fuel cell 20, the opening degree of the valve V105 is increased and the hydrogen supply amount to the fuel cell 20 is increased. This state is maintained in step 205 until the operation mode is changed.

  If it is determined in step 203 that the hot water supply priority mode is not selected, the process proceeds to step 207 to determine whether or not the power generation priority mode is selected. If it is determined that the power generation priority mode is selected, the process proceeds to step 209, and the opening degrees of the valves V102 and V105 are increased. Thereby, the amount of hydrogen and oxygen supplied to the fuel cell 20 is increased, and the power generation amount of the fuel cell 20 is increased. This state is maintained in step 209 until the operation mode is changed.

  If it is determined in step 207 that the power generation priority mode is not selected, the process proceeds to step 211 to determine whether the fatigue recovery priority mode is selected. When the fatigue recovery priority mode is selected, the process proceeds to step 213, and the opening degrees of the valves V101, V103, V105 are increased. Thus, the supply amount of oxygen to the air conditioner 702 is increased by increasing the opening degree of the valve V103. From the air conditioner 702, conditioned air with an increased oxygen concentration is released, which contributes to recovery of user fatigue. The shortage of oxygen supplied to the fuel cell 20 is compensated by increasing the air supply amount by increasing the opening of the valve V101. At this time, since the exhaust gas loss increases, in order to maintain the power generation amount, the opening degree of the valve V105 is increased and the hydrogen supply amount to the fuel cell 20 is increased. This state is maintained in step 213 until the operation mode is changed.

When it is determined in step 211 that the fatigue recovery mode is not selected, the process proceeds to step 215, and it is determined whether the gas combustion device priority mode is selected. If it is determined that the gas combustion device priority mode is selected, the routine proceeds to step 217, where the opening degree of the valves V101, V104, V106 is increased. Thus, by increasing the opening degree of the valves V104 and V106, the supply amount of hydrogen and oxygen to the gas combustion device 703 can be increased. Thus, for example, the heating power of a gas range (gas cooker) as an example of the gas combustion device 703 can be increased.
If any of Steps 205, 209, 213, and 217 is completed, the process proceeds to Step 219, and the power generation efficiency of the fuel cell 20 is maximized based on the normal control, that is, the amount of hydrogen that can be supplied from the hydrogen pressure vessel 31. Control. Then, the control of FIG. 4 ends. If it is determined in step 215 that the gas combustion device priority mode is not selected, the control in FIG.

When the hydrogen supply amount to the fuel cell 20 is insufficient in each of the above operation modes, the reformed gas can be supplied from the city gas reforming line 35 to the fuel cell 20 by increasing the opening of the valve V107. it can. Similarly, when the amount of hydrogen supplied to the gas combustion device 703 is insufficient, the city gas can be supplied from the city gas line 36 to the gas combustion device 70 by increasing the opening of the valve V108.
The above-described gas utilization device, operation mode, and valve operation method are merely examples, and other various gas utilization devices, operation modes, and valve operation methods can be employed.
For example, in the above embodiment, only one operation mode can be selected, but instead, a plurality of operation modes may be selected simultaneously. In this case, the opening degree of each valve may be proportionally distributed and controlled with respect to a plurality of requested gas supply amounts in a plurality of operation modes. Specifically, for example, when priority is given to both fatigue recovery and gas combustion equipment at the same time, the opening degree of the valves V103 and V104 is increased so as to be proportional to the oxygen demand of the air conditioner 702 and the gas combustion equipment 703. The amount can be determined.

Instead of the fuel cell 20, a power generation device such as a gas turbine generator may be used. When the city gas can be directly used for the power generation apparatus, the city gas line 36 can be used instead of the city gas reforming line 35.
Further, the reformed gas from the city gas reforming line 35 may be supplied to the gas combustion device 703 without providing the city gas line 36.

When the daily illuminance with respect to the electrode decreases, the water splitting efficiency by the photoelectrode decreases, and the amount of hydrogen generated by the water splitting module 3 may be insufficient. In such a case, the opening amounts of the valves V107 and V108 may be increased to increase the supply amount of city gas reformed gas or city gas. In that case, you may make it adjust the opening degree of valve | bulb V107, V108 according to a day illumination intensity.
On the contrary, when the illuminance is high or when the fuel cell 20 or the gas using device 70 is not used, when hydrogen or oxygen generated in the water splitting module 3 becomes excessive, the hydrogen pressure vessel 31, the hydrogen vessel 32, And the oxygen pressure vessel 33 may be stored respectively.
In the above embodiment, the case where a power source for applying a voltage between electrodes is connected has been described. However, if a photo semiconductor catalyst capable of decomposing water into hydrogen and oxygen with only solar energy is used, it is not necessary to connect a power source.

  The present invention is not limited to the description of the embodiment and examples of the invention. Various modifications are also included in the present invention as long as those skilled in the art can easily conceive without departing from the scope of the claims.

1 Solar power system 3 Water splitting module (water splitting section)
20 Fuel cell (gas utilization equipment, power generator)
21 Heat exchanger 31 Hydrogen pressure vessel 33 Oxygen pressure vessel 35, 36 Pressure gauge V34 Valve (hydration valve)
40 Circulation Line 41 Circulation Pump 44 Water Supply Unit 50 Water Level Meter 60 Day Illuminance Meter 70 Gas Utilization Equipment 71 Gas Distribution Control Unit (Gas Supply Unit)
80 Control circuit 81 External power supply

Claims (2)

A water-splitting part having a pair of electrodes carrying a photo-semiconductor catalyst on one side and decomposing an electrolyte solution using solar energy irradiated to the photo-semiconductor catalyst;
A fuel cell that generates electricity using hydrogen generated by the decomposition of the electrolyte; and
A water replenishment unit for replenishing the water generated in the fuel cell to the electrolyte of the water splitting unit;
A control circuit that calculates the amount of water consumed in the electrolytic solution of the water splitting unit and the amount of generated water that can be supplied from the fuel cell to the water splitting unit, and controls the amount of water added to the water replenishing unit And a solar light utilization system. The water splitting unit has a water level meter for measuring the water level of the electrolytic solution tank, and the control circuit compares the water level of the electrolytic solution tank in the electrolytic solution tank with a predetermined threshold value, and the water level of the electrolytic solution is when it is outside the predetermined threshold range, as if an abnormal situation occurs, the sunlight utilization system according to claim 1, wherein operating the alarm.

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