JP2013044032A - Power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation system which suppresses the occurrence of power shortage when power sources are switched.SOLUTION: The power generation system includes: a water electrolysis part 21 for generating hydrogen gas and oxygen gas by electrolyzing water; a photoelectric conversion part 2 for outputting photovoltaic power generated by the reception of sunlight to the outside or the water electrolysis part 21; a fuel cell part 22 for generating an electric power by using hydrogen gas as a fuel and outputting the generated electric power to the outside according to the demand power or the photovoltaic power of the photoelectric conversion part 2; a hydrogen storage part 12 for storing hydrogen gas generated in the water electrolysis part 21 and supplying the stored hydrogen gas to the fuel cell part; a humidity adjusting part 10 for adjusting the humidity of hydrogen gas or air supplied to the fuel cell part; and a control part 17. The control part has a function to control the humidity adjusting part based on the information related to the photovoltaic power of the photoelectric conversion part 2 or the information related to the demand power.

Description

  The present invention relates to a power generation system using sunlight.

  In recent years, the use of renewable energy has been desired from the viewpoint of depletion of fossil fuel resources and the suppression of global warming gas emissions. There are a wide variety of renewable energy sources such as solar, hydropower, wind power, geothermal, tidal power, and biomass. Because of the relatively small amount, early development and popularization of technology that can efficiently use energy from sunlight is desired.

  Possible forms of energy generated from sunlight include electrical energy produced using solar cells and solar thermal turbines, thermal energy by collecting solar energy in a heat medium, and other types of sunlight. Examples include storable fuel energy such as liquid fuel and hydrogen by substance reduction. Many solar cell technologies and solar heat utilization technologies have already been put into practical use, but the energy utilization efficiency is still low, and the cost of producing electricity and heat is still high. Technology development is underway. Furthermore, while these forms of electricity and heat can be used to supplement short-term energy fluctuations, it is extremely difficult to supplement long-term fluctuations such as seasonal fluctuations, It is a problem that there is a possibility that the operating rate of the power generation equipment may be reduced due to the increase in power generation. On the other hand, storing energy as a substance, such as liquid fuel and hydrogen, is extremely effective as a technology that efficiently supplements long-term fluctuations and increases the operating rate of power generation facilities. It is an indispensable technology to raise and reduce carbon dioxide emissions thoroughly.

  The types of fuel that can be stored are roughly divided into liquid fuels such as hydrocarbons, gaseous fuels such as biogas and hydrogen, solid pellets such as biomass-derived wood pellets and metals reduced by sunlight. it can. In terms of ease of infrastructure development and energy density, liquid fuel, gaseous fuel including hydrogen in terms of total utilization efficiency improvement with fuel cells, etc., solid fuel in terms of storability and energy density, Although each form has advantages and disadvantages, a hydrogen production technique by decomposing water with sunlight has attracted particular attention from the viewpoint that water that can be easily obtained as a raw material can be used.

As a method of producing hydrogen using solar energy using water as a raw material, platinum is supported on a photocatalyst such as titanium oxide, and this substance is put in water to perform light separation in a semiconductor, and an electrolytic solution. The water is decomposed directly at high temperature using the photolysis method by reducing protons and oxidizing water, or by using thermal energy such as a high-temperature gas furnace, or indirectly by coupling with redox of metals, etc. Pyrolysis method that uses the metabolism of microorganisms that use light such as algae, water electrolysis method that combines electricity generated by solar cells and water electrolysis hydrogen production equipment, photoelectric conversion used in solar cells Examples of the method include a photovoltaic method in which electrons and holes obtained by photoelectric conversion are used in a reaction by a hydrogen generation catalyst and an oxygen generation catalyst by supporting a hydrogen generation catalyst and an oxygen generation catalyst on the material. Among these, the one that has the possibility of producing a small hydrogen production device by integrating the photoelectric conversion unit and the hydrogen generation unit is considered to be a photolysis method, a biological method, a photovoltaic method, From the viewpoint of the conversion efficiency of solar energy, the photovoltaic method is considered to be one of the technologies closest to practical use.
So far, a hydrogen production apparatus has been disclosed in which hydrogen is generated by photoelectric conversion and electrolysis of an electrolytic solution using the photovoltaic power (for example, Patent Document 1). By using such a hydrogen production apparatus, solar energy can be efficiently stored as hydrogen.

  In addition, a distributed energy system that includes a power generation device, a power storage device, a heat storage device, and a hydrogen storage device and optimizes energy operation is known (for example, Patent Document 2), and a fuel cell and a water electrolyzer are integrated. Such a fuel cell is known (for example, Patent Document 3).

Japanese Patent No. 4559438 JP 2004-31798 A Japanese Patent No. 4035313

However, in the conventional energy system, switching of the power source has not been sufficiently studied, and thus efficient and stable power supply is not performed.
The present invention has been made in view of such circumstances, and provides a power generation system capable of generating power and supplying power efficiently and stably.

  The present invention includes a water electrolysis unit that electrolyzes water to generate hydrogen gas and oxygen gas, a photoelectric conversion unit that outputs photovoltaic power generated by receiving sunlight to an external output or the water electrolysis unit, and a demand According to the electric power or the photovoltaic power of the photoelectric conversion unit, the fuel cell unit that generates hydrogen gas as fuel and outputs the electromotive force to the outside, the hydrogen gas generated by the water electrolysis unit is stored, and the stored hydrogen gas A hydrogen storage unit that supplies the fuel cell unit, a humidity control unit that adjusts the humidity of hydrogen gas or air supplied to the fuel cell unit, and a control unit, wherein the control unit includes A power generation system comprising a function of controlling the humidity control unit based on information on photovoltaic power or information on demand power is provided.

According to the present invention, a water electrolysis unit that electrolyzes water to generate hydrogen gas and oxygen gas, a photoelectric conversion unit that outputs a photovoltaic power generated by receiving sunlight to an external output or the water electrolysis unit, And a hydrogen storage unit that stores the hydrogen gas generated by the water electrolysis unit, so that when the power demand is high, the photovoltaic power of the photoelectric conversion unit can be output to the outside. In addition, when the power demand is small, the photovoltaic power of the photoelectric conversion unit can be output to the water electrolysis unit to electrolyze the water and generate hydrogen gas, and the generated hydrogen gas is stored in the hydrogen storage unit be able to. As a result, the energy of sunlight can be stored as hydrogen gas as fuel for the fuel cell.
According to the present invention, a hydrogen storage unit that supplies stored hydrogen gas to the fuel cell unit, a fuel cell unit that generates electricity using hydrogen gas as fuel and outputs an electromotive force to the outside, hydrogen gas supplied to the fuel cell unit or And a humidity control unit that adjusts the humidity of the air, so that when the photovoltaic power of the photoelectric conversion unit decreases or when the power demand increases, the fuel cell unit generates power to satisfy the power demand. Can be output. This can suppress the occurrence of power shortage. Further, since the fuel cell unit can use the hydrogen gas generated by the water electrolysis unit and stored in the hydrogen storage unit as fuel, it can output electric power from sunlight as an energy source.
According to the present invention, since the control unit has a function of controlling the humidity control unit based on the information about the photovoltaic power of the photoelectric conversion unit or the information about the demand power, before starting the supply of hydrogen gas or air to the fuel cell unit In addition, the humidity control unit can be controlled so that the humidity control unit can be humidified. Thus, the humidified hydrogen gas or air can be quickly supplied to the fuel cell unit, and the fuel cell unit can quickly output the generated power to the outside. As a result, even when a fuel cell unit is added to the power source, it is possible to immediately respond to the power demand, and to generate power and supply power efficiently and stably.

It is a conceptual diagram of the electric power generation system of one Embodiment of this invention. 1 is a schematic piping diagram of a power generation system according to an embodiment of the present invention. 1 is a schematic circuit diagram of a power generation system according to an embodiment of the present invention. 1 is a schematic circuit diagram of a power generation system according to an embodiment of the present invention. It is a schematic plan view which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing of the hydrogen production apparatus in dotted line AA of FIG. It is a schematic back view which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the fuel cell part contained in the electric power generation system of one Embodiment of this invention. 1 is a schematic circuit diagram of a power generation system according to an embodiment of the present invention. 1 is a schematic circuit diagram of a power generation system according to an embodiment of the present invention. 1 is a schematic circuit diagram of a power generation system according to an embodiment of the present invention. It is a flowchart of the control method of the control part contained in the electric power generation system of one Embodiment of this invention. It is a flowchart of the control method of the control part contained in the electric power generation system of one Embodiment of this invention.

The power generation system of the present invention includes a water electrolysis unit that electrolyzes water to generate hydrogen gas and oxygen gas, and a photoelectric conversion unit that outputs photovoltaic power generated by receiving sunlight to an external output or the water electrolysis unit And storing the hydrogen gas generated by the water electrolysis unit and the fuel cell unit that generates hydrogen gas as fuel and outputs the electromotive force to the outside according to the demand power or the photovoltaic power of the photoelectric conversion unit A hydrogen storage unit for supplying the hydrogen gas to the fuel cell unit, a humidity control unit for adjusting the humidity of the hydrogen gas or air supplied to the fuel cell unit, and a control unit,
The said control part is provided with the function to control the said humidity control part based on the information regarding the photovoltaic power of the said photoelectric conversion part, or the information regarding demand power.

In the power generation system of the present invention, the control unit is configured to control the humidity control unit before starting supply of hydrogen gas or air to the fuel cell unit based on information on photovoltaic power and information on demand power of the photoelectric conversion unit. It is preferable to have a function of controlling the humidity control unit so that the humidity can be humidified.
According to such a configuration, the humidified hydrogen gas or air can be quickly supplied to the fuel cell unit, and the fuel cell unit can quickly output the generated power to the outside. As a result, even when a fuel cell unit is added to the power source, it is possible to immediately respond to the power demand, and to generate power and supply power efficiently and stably.
In the power generation system of the present invention, the control unit is configured to start the supply of hydrogen gas or air to the fuel cell unit based on the information about the photovoltaic power of the photoelectric conversion unit and the information about demand power. It is preferable to further include a function of controlling the fuel cell unit so as to raise the temperature to a predetermined temperature that is lower than the operating temperature.
According to such a configuration, the fuel cell unit can be quickly raised to the operating temperature, and the fuel cell unit can quickly output the generated power to the outside. As a result, even when the fuel cell unit is added to the power source, it is possible to immediately respond to the power demand, and to suppress the temporary shortage of power.
In the power generation system of the present invention, it is preferable that the humidity control unit adjusts the humidity of hydrogen gas stored in the hydrogen storage unit.
According to such a configuration, the hydrogen gas generated by the water electrolysis unit can be dehumidified by the humidity control unit and stored in the hydrogen storage unit.

In the power generation system of the present invention, it is preferable that the humidity adjusting unit includes a humidifying unit and a dehumidifying unit.
According to such a configuration, the humidification of the hydrogen gas and air supplied to the fuel cell unit by the humidity control unit can be performed. Further, the humidity adjustment unit can dehumidify the hydrogen gas generated by the water electrolysis unit.
The power generation system of the present invention further includes a hydrogen flow path, wherein the hydrogen flow path is a path where hydrogen gas generated by the water electrolysis unit flows through the dehumidification unit and is stored in the hydrogen storage unit, and the fuel It is preferable that hydrogen gas serving as a fuel for the battery unit flows through the humidification unit and is supplied to the fuel cell unit.
According to such a configuration, the hydrogen gas generated by the water electrolysis unit can be stored in the hydrogen storage unit, and the hydrogen gas serving as the fuel of the fuel cell unit can be humidified and supplied to the fuel cell unit. .

In the power generation system of the present invention, it is preferable that the hydrogen flow path has a plurality of valves provided so that a path through which hydrogen gas flows can be changed.
According to such a configuration, the path through which hydrogen gas flows can be changed by the plurality of valves.
The power generation system of the present invention preferably further includes a switching unit that switches between a circuit that outputs the photovoltaic power of the photoelectric conversion unit to the water electrolysis unit and a circuit that outputs the photovoltaic power of the photoelectric conversion unit to the outside. .
According to such a configuration, the output destination of the photovoltaic power of the photoelectric conversion unit can be changed by the switching unit.

In the power generation system of the present invention, the switching unit is provided so that one or both of the photovoltaic power of the photoelectric conversion unit and the generated power of the fuel cell unit can be switched and output to the outside. preferable.
According to such a configuration, one or both of the photovoltaic power of the photoelectric conversion unit and the generated power of the fuel cell unit can be switched and output to the outside by the switching unit.
In the power generation system of the present invention, the control unit is set by an input unit that inputs information, a setting unit that sets a control mode of the power generation system based on information input from the input unit, and the setting unit. It is preferable to provide output means for outputting information to the components of the power generation system.
According to such a configuration, the control mode of the power generation system can be switched by the control unit.

The power generation system of the present invention preferably further includes a sensor unit including a solar radiation meter or an illuminance sensor, and the input means inputs information from the sensor unit.
According to such a configuration, the control unit can switch the control mode of the power generation system based on information from the sensor unit.
In the power generation system of the present invention, it is preferable that the input means inputs information from an electric power company, Web information, and solution server information.
According to such a configuration, the control unit can switch the control mode of the power generation system based on information from the electric power company, Web information, and solution server information.

In the power generation system of the present invention, the photoelectric conversion unit has a light receiving surface and the back surface thereof, the water electrolysis unit is provided on the back side of the photoelectric conversion unit, the photoelectric conversion unit and the water electrolysis unit, It is preferable to constitute a hydrogen production apparatus.
According to such a configuration, the wiring distance between the photoelectric conversion unit and the water electrolysis unit can be shortened, and the ohmic cross can be reduced.
In the power generation system of the present invention, the hydrogen production apparatus includes a first electrolysis electrode and a second electrolysis electrode provided on a back surface of the photoelectric conversion unit, and sunlight is formed on a light receiving surface of the photoelectric conversion unit. When the first and second electrolysis electrodes come into contact with the electrolytic solution, the first and second electrolysis electrodes electrolyze the electrolytic solution using electromotive force generated by the photoelectric conversion unit receiving light. Preferably, the first gas and the second gas are generated, respectively, and one of the first gas and the second gas is preferably hydrogen gas and the other is oxygen gas.
According to such a configuration, the first and second electrolysis electrodes constituting the hydrogen production apparatus use the electromotive force generated by the photoelectric conversion unit to receive light to electrolyze the electrolytic solution, respectively, Since the second gas is provided so as to be generated, the first gas can be generated on the surface of the first electrolysis electrode, and the second gas can be generated on the surface of the second electrolysis electrode. In addition, since the first electrolysis electrode and the second electrolysis electrode are provided on the back surface of the photoelectric conversion unit, light can be incident on the light receiving surface of the photoelectric conversion unit without using the electrolytic solution, and the incident light from the electrolytic solution Absorption and scattering of incident light can be prevented. As a result, the amount of incident light to the photoelectric conversion unit can be increased, and the light use efficiency can be increased. In addition, since the first electrolysis electrode and the second electrolysis electrode are provided on the back surface of the photoelectric conversion portion, the light incident on the light receiving surface is generated by the first and second electrolysis electrodes and the first gas generated from the first and second electrolysis electrodes, respectively. And it is not absorbed or scattered by the second gas. As a result, the amount of incident light to the photoelectric conversion unit can be increased, and the light use efficiency can be increased.

In the power generation system of the present invention, the photoelectric conversion unit receives an electromotive force to generate an electromotive force between the light receiving surface and the back surface, and the first electrolysis electrode is electrically connected to the back surface of the photoelectric conversion unit. The second electrolysis electrode is preferably provided so as to be electrically connected to the light receiving surface of the photoelectric conversion unit.
According to such a structure, the thing of a laminated structure can be utilized for the photoelectric conversion part contained in a hydrogen production apparatus.
In the power generation system of the present invention, it is preferable that the hydrogen production apparatus further includes an insulating part provided between the second electrolysis electrode and the back surface of the photoelectric conversion part.
According to such a configuration, it is possible to prevent a leak current from being generated between the second electrolysis electrode and the back surface of the photoelectric conversion unit in the hydrogen production apparatus.

In the power generation system of the present invention, it is preferable that the hydrogen production apparatus further includes a first electrode that contacts a light receiving surface of the photoelectric conversion unit.
According to such a configuration, the internal resistance in the hydrogen production apparatus can be reduced.
In the power generation system of the present invention, it is preferable that the hydrogen production apparatus further includes a first conductive portion that electrically connects the first electrode and the second electrode for electrolysis.
According to such a structure, the light-receiving surface of a photoelectric conversion part and the 2nd electrode for electrolysis can be electrically connected.

In the power generation system of the present invention, it is preferable that the first conductive portion is provided in a contact hole that penetrates the photoelectric conversion portion.
According to such a configuration, the wiring distance between the light receiving surface of the photoelectric conversion unit and the second electrolysis electrode can be shortened, and the internal resistance can be reduced.
In the power generation system of the present invention, the insulating part is provided so as to cover a side surface of the photoelectric conversion part, and the first conductive part is a part of the insulating part and covers a side surface of the photoelectric conversion part. It is preferable to be provided.
According to such a configuration, the first conductive portion can be provided with a small number of steps, and the manufacturing cost can be reduced.

In the power generation system of the present invention, the insulating part is provided so as to cover a side surface of the photoelectric conversion part, and the second electrolysis electrode is a part of the insulating part and covers a side surface of the photoelectric conversion part. It is preferable that the first electrode is provided on the upper surface and in contact with the first electrode.
According to such a configuration, the first electrode and the second electrolysis electrode can be electrically connected without providing the first conductive portion.
In the power generation system of the present invention, it is preferable that the photoelectric conversion unit has a photoelectric conversion layer including a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer.
According to such a configuration, an electromotive force can be generated by causing light to enter the photoelectric conversion unit.

In the power generation system of the present invention, the photoelectric conversion unit receives a light to generate a potential difference between the first and second areas on the back surface of the photoelectric conversion unit, and the first area is electrically connected to the first electrolysis electrode. Preferably, the second section is provided so as to be electrically connected to the second electrolysis electrode.
According to such a configuration, the electromotive force generated between the first area and the second area of the photoelectric conversion unit can be output to the first electrolysis electrode and the second electrolysis electrode.
In the power generation system of the present invention, the hydrogen production apparatus is provided between the first and second electrolysis electrodes and the back surface of the photoelectric conversion unit, and has openings on the first area and the second area. It is preferable to further include an insulating part.
According to such a configuration, an electromotive force generated when the photoelectric conversion unit receives light can be efficiently generated between the first area and the second area.

In the power generation system of the present invention, the photoelectric conversion part is made of at least one semiconductor material having an n-type semiconductor part and a p-type semiconductor part, and one of the first and second areas is one of the n-type semiconductor part. It is preferable that the other is a part of the p-type semiconductor part.
According to such a configuration, an electromotive force can be generated between the first and second areas on the back surface of the photoelectric conversion unit when the photoelectric conversion unit receives light.
In the power generation system of the present invention, it is preferable that the hydrogen production apparatus further includes a translucent substrate, and the photoelectric conversion unit is provided on the translucent substrate.
According to such a structure, a photoelectric conversion part can be formed on a translucent board | substrate.

In the power generation system of the present invention, the photoelectric conversion unit includes a plurality of photoelectric conversion layers connected in series, and the plurality of photoelectric conversion layers generate an electromotive force generated by receiving light in the first electrolysis electrode and the second electrolysis electrode. It is preferable to be provided so as to be supplied to the electrode.
According to such a configuration, a high voltage electromotive force can be easily output to the first and second electrolysis electrodes.
In the power generation system of the present invention, one of the first electrolysis electrode and the second electrolysis electrode is a hydrogen generation unit that generates H ₂ from the electrolytic solution, and the other is an oxygen generation unit that generates O ₂ from the electrolytic solution. The hydrogen generation part and the oxygen generation part each include a hydrogen generation catalyst that is a catalyst for generating H ₂ from the electrolytic solution and an oxygen generation catalyst that is a catalyst for generating O ₂ from the electrolytic solution. It is preferable.
According to such a configuration, hydrogen gas serving as fuel for the fuel cell can be produced by the hydrogen production apparatus.

In the power generation system of the present invention, it is preferable that at least one of the hydrogen generation unit and the oxygen generation unit has a catalyst surface area larger than an area of a light receiving surface of the photoelectric conversion unit.
According to such a configuration, hydrogen gas and oxygen gas can be more efficiently produced by the hydrogen production apparatus.
In the power generation system of the present invention, it is preferable that at least one of the hydrogen generation unit and the oxygen generation unit is a porous conductor carrying a catalyst.
According to such a configuration, the catalyst area for the reaction in which hydrogen gas or oxygen gas is generated can be increased.

In the power generation system of the present invention, it is preferable that the hydrogen generation catalyst includes at least one of Pt, Ir, Ru, Pd, Rh, Au, Fe, Ni, and Se.
According to such a configuration, hydrogen gas can be efficiently generated from the electrolytic solution by the hydrogen production apparatus.
In the power generation system of the present invention, it is preferable that the oxygen generation catalyst includes at least one of Mn, Ca, Zn, Co, and Ir.
According to such a configuration, oxygen gas can be efficiently generated from the electrolytic solution by the hydrogen production apparatus.

In the power generation system of the present invention, the hydrogen production apparatus further includes a translucent substrate, an electrolyte chamber, and a back substrate provided on the first electrolysis electrode and the second electrolysis electrode, It is preferable that the conversion unit is provided on the translucent substrate, and the electrolytic solution chamber is provided between the first electrolysis electrode and the second electrolysis electrode and the back substrate.
According to such a configuration, the surface of the first electrolysis electrode that can contact the electrolyte solution and the surface of the second electrolysis electrode that can contact the electrolyte solution can be provided facing the electrolyte chamber, The first and second electrodes for electrolysis can be brought into contact with the electrolytic solution.
In the power generation system of the present invention, the hydrogen production apparatus includes a partition wall that partitions the electrolyte chamber between the first electrolysis electrode and the back substrate and the electrolyte chamber between the second electrolysis electrode and the back substrate. It is preferable to further comprise.
According to such a configuration, the first gas and the second gas can be separated by the partition wall.
In the power generation system of the present invention, the partition preferably includes an ion exchanger.
According to such a structure, the imbalance of the ion concentration which arises in electrolyte solution can be eliminated easily.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are merely examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

Diagram 1 of the power generation system is a conceptual diagram of the power generation system of this embodiment, FIG. 2 is a schematic piping diagram of the power generation system of the present embodiment, FIG. 3, FIG. 4 is a schematic circuit of the power generation system of this embodiment FIG.
The power generation system of the present embodiment includes a water electrolysis unit 21 that electrolyzes water to generate hydrogen gas and oxygen gas, and a photoelectric that outputs photovoltaic power generated by receiving sunlight to an external output or the water electrolysis unit 21. In accordance with the conversion unit 2, the demand power or the photovoltaic power of the photoelectric conversion unit 2, the fuel cell unit 22 that generates hydrogen gas as fuel and outputs the electromotive force to the outside, and the hydrogen gas generated by the water electrolysis unit 21 A hydrogen storage unit 12 that stores and supplies the stored hydrogen gas to the fuel cell unit 22, a humidity control unit 10 that adjusts the humidity of the hydrogen gas or air supplied to the fuel cell unit 22, and a control unit 17. The control unit 17 has a function of controlling the humidity control unit 10 based on information on the photovoltaic power of the photoelectric conversion unit 2 or information on demand power.

1. Photoelectric conversion unit 2
The photoelectric conversion unit 2 is a portion where photovoltaic power is generated by receiving sunlight, and outputs the electromotive force to an external output or the water electrolysis unit 21. By outputting the photovoltaic power of the photoelectric conversion unit 2 to the outside, this power can be used in an external circuit. In addition, by outputting the photovoltaic power of the photoelectric conversion unit 2 to the water electrolysis unit 21, water can be electrolyzed using the photovoltaic power to generate hydrogen gas and oxygen gas. Thereby, when there is little electric power demand or when the photovoltaic power of the photoelectric conversion unit 2 is large, hydrogen gas can be generated by the photovoltaic power of the photoelectric conversion unit 2. The hydrogen gas can be stored in the hydrogen storage unit 12 after being dehumidified by the dehumidifying unit 49 through the hydrogen flow path from the water electrolysis unit 21.

  The photoelectric conversion unit 2 can be electrically connected to the switching unit 29 in order to output the photovoltaic power generated by receiving sunlight to the external output or the water electrolysis unit 21. As a result, the output destination of the photovoltaic power of the photoelectric conversion unit 2 can be switched by the switching unit 29.

The photoelectric conversion unit 2 is not particularly limited as long as a photovoltaic power is generated by receiving sunlight. For example, a photoelectric conversion unit using a silicon-based semiconductor, a photoelectric conversion unit using a compound semiconductor, and dye enhancement These include a photoelectric conversion unit using a sensitizer and a photoelectric conversion unit using an organic thin film.
Moreover, the photoelectric conversion unit 2 may be included in a hydrogen production apparatus 23 described later. A description of the photoelectric conversion unit 2 in this case will be described later. The description of the photoelectric conversion unit 2 included in the hydrogen production apparatus 23 is applicable to the photoelectric conversion unit 2 not included in the hydrogen production apparatus 23 as long as there is no contradiction.
Moreover, the photoelectric conversion part 2 may be plural. For example, you may consist of a several solar cell panel and the hydrogen production apparatus mentioned later. In this case, the photovoltaic power of the photoelectric conversion unit 2 included in the hydrogen production apparatus may be output to the water electrolysis unit 21 and the photovoltaic power of the solar cell panel may be output to the outside. Moreover, you may output the photovoltaic power of a solar cell panel to the water electrolysis part 21. FIG. Moreover, you may output externally all the photovoltaic power of the photoelectric conversion part 2 contained in a hydrogen production apparatus, and the photovoltaic power of a solar cell panel. In this case, the power generation system can have a circuit diagram as shown in FIG.

2. Water Electrolysis Unit The water electrolysis unit 21 can electrolyze water using the photovoltaic power of the photoelectric conversion unit 2 to generate hydrogen gas and oxygen gas. The water electrolysis unit 21 can be an electrolytic cell including the first electrolysis electrode 8 and the second electrolysis electrode 7. The electrolytic solution is stored in the electrolytic cell, and the photovoltaic power of the photoelectric conversion unit 2 is output to the first and second electrolysis electrodes 8 and 7, thereby electrolyzing the water contained in the electrolytic solution to generate hydrogen gas and oxygen. Gas can be generated.
Further, the water electrolysis unit 21 may be included in a hydrogen production apparatus 23 described later. The description of the first electrolysis electrode 8 and the second electrolysis electrode 7 in this case will be described later. The description of the first electrolysis electrode 8 and the second electrolysis electrode 7 included in the hydrogen production apparatus 23 also applies to the first electrolysis electrode 8 and the second electrolysis electrode 7 that are not included in the hydrogen production apparatus 23. This is true as long as there is no contradiction.

3. Hydrogen Production Device FIG. 5 is a schematic plan view showing the configuration of the hydrogen production device included in the power generation system of the present embodiment, and FIG. FIG. 7 is a schematic back view showing the configuration of the hydrogen production apparatus included in the power generation system of the present embodiment.
Moreover, FIGS. 8-14 is a schematic sectional drawing which shows the structure of the hydrogen production apparatus contained in the electric power generation system of this embodiment, respectively, and is a schematic sectional drawing corresponding to FIG.
The hydrogen production apparatus 23 can include a photoelectric conversion unit 2 having a light receiving surface and a back surface thereof, and a water electrolysis unit 21 provided on the back surface side of the photoelectric conversion unit 2.
Further, the hydrogen production apparatus 23 has a first electrolysis electrode 8 and a second electrolysis electrode 7 respectively provided on the back surface of the photoelectric conversion unit 2, and sunlight enters the light receiving surface of the photoelectric conversion unit 2. When the first and second electrolysis electrodes 8 and 7 are in contact with the electrolytic solution, the first and second electrolysis electrodes 8 and 7 utilize the electromotive force generated by the photoelectric conversion unit 2 receiving light. Of the first gas and the second gas, one of which is hydrogen gas and the other is oxygen gas.

The first and second electrolysis electrodes 8 and 7 are provided so as to electrolyze the electrolytic solution using electromotive force generated when the photoelectric conversion unit 2 receives light to generate a first gas and a second gas, respectively. Therefore, the first gas can be generated on the surface of the first electrolysis electrode 8, and the second gas can be generated on the surface of the second electrolysis electrode 7. Moreover, since one of the first gas and the second gas is hydrogen gas, hydrogen gas can be produced.
Further, since the first electrolysis electrode 8 and the second electrolysis electrode 7 are provided on the back surface of the photoelectric conversion unit 2, light can be incident on the light receiving surface of the photoelectric conversion unit 2 without passing through the electrolyte solution. It is possible to prevent absorption of incident light and scattering of incident light. As a result, the amount of incident light to the photoelectric conversion unit 2 can be increased, and the light use efficiency can be increased.
Further, since the first electrolysis electrode 8 and the second electrolysis electrode 7 are provided on the back surface of the photoelectric conversion unit 2, the light incident on the light receiving surface is transmitted from the first and second electrolysis electrodes 8, 7 and from there. It is not absorbed or scattered by the first gas and the second gas generated respectively. As a result, the amount of light incident on the photoelectric conversion unit 2 can be increased, and the light use efficiency can be increased.

Moreover, the hydrogen production apparatus 23 can also have the translucent substrate 1, the 1st electrode 4, the 2nd electrode 5, the 1st electroconductive part 9, etc.
Hereinafter, the hydrogen production apparatus 23 will be described.

3-1. Translucent substrate The translucent substrate 1 may be provided in the hydrogen production apparatus 23. Moreover, the photoelectric conversion part 2 may be provided on the translucent board | substrate 1 so that a light-receiving surface may become the translucent board | substrate 1 side. In addition, when the photoelectric conversion part 2 consists of semiconductor substrates etc. and has fixed intensity | strength, the translucent board | substrate 1 can be abbreviate | omitted. Moreover, when the photoelectric conversion part 2 can be formed on a flexible material such as a resin film, the translucent substrate 1 can be omitted.

In addition, since the sunlight is received by the light receiving surface of the photoelectric conversion unit 2, the translucent substrate 1 is preferably transparent and has high light transmittance. However, it is possible to efficiently enter the photoelectric conversion unit 2. If it is a simple structure, there is no restriction | limiting in the light transmittance.
As a substrate material having a high light transmittance, for example, a transparent rigid material such as soda glass, quartz glass, Pyrex (registered trademark), or a synthetic quartz plate, or a transparent resin plate or film material is preferably used. In view of chemical and physical stability, it is preferable to use a glass substrate.
On the surface of the translucent substrate 1 on the photoelectric conversion unit 2 side, a fine uneven structure can be formed so that incident light is effectively irregularly reflected on the surface of the photoelectric conversion unit 2. This fine concavo-convex structure can be formed by a known method such as reactive ion etching (RIE) treatment or blast treatment.

3-2. 1st electrode The 1st electrode 4 can be provided on the translucent board | substrate 1, and can be provided so that the light-receiving surface of the photoelectric conversion part 2 may be contacted. Moreover, the 1st electrode 4 may have translucency. Moreover, the 1st electrode 4 may be directly provided in the light-receiving surface of the photoelectric conversion part 2, when the translucent board | substrate 1 can be abbreviate | omitted. The first electrode 4 can be electrically connected to the second electrolysis electrode 7. By providing the first electrode 4, the current flowing between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7 can be increased. Moreover, when the photoelectric conversion part 2 produces an electromotive force between the 1st area and the 2nd area of the back surface of the photoelectric conversion part 2 like FIG. 13, 14, the 1st electrode 4 is unnecessary.
The first electrode 4 may be electrically connected to the second electrolysis electrode 7 via the first conductive portion 9 as shown in FIGS. 6, 9, and 12, and the second electrolysis electrode 7 as shown in FIG. You may contact with. 8 and 10, the first electrode 4 can be electrically connected to the second electrolysis electrode 7 via the switching unit 29 and the wiring 50.
The first electrode 4 may be made of a transparent conductive film such as ITO or SnO _2, or may be made of a metal finger electrode such as Ag or Au.

A case where the first electrode 4 is a transparent conductive film will be described below.
The transparent conductive film can be used to facilitate contact between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7.
What is generally used as a transparent electrode can be used. Specifically, In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, SnO _{2 and the} like can be given. The transparent conductive film preferably has a sunlight transmittance of 85% or more, particularly 90% or more, and particularly 92% or more. This is because the photoelectric conversion unit 2 can absorb light efficiently.
As a method for producing the transparent conductive film, a known method can be used, and examples thereof include sputtering, vacuum deposition, sol-gel method, cluster beam deposition method, and PLD (Pulse Laser Deposition) method.

3-3. Photoelectric Conversion Unit The photoelectric conversion unit 2 has a light receiving surface and a back surface thereof, and a first electrolysis electrode 8 and a second electrolysis electrode 7 are provided on the back surface side of the photoelectric conversion unit 2. The light receiving surface is a surface that receives light for photoelectric conversion, and the back surface is the back surface of the light receiving surface. Moreover, the photoelectric conversion part 2 can be provided on the translucent substrate 1 provided with the first electrode 4 with the light receiving surface facing down. For example, an electromotive force may be generated between the light receiving surface and the back surface of the photoelectric conversion unit 2 as illustrated in FIGS. 6 and 8 to 12. An electromotive force may be generated between the first area and the second area. The photoelectric conversion unit 2 as shown in FIGS. 13 and 14 can be formed by a semiconductor substrate on which the n-type semiconductor region 37 and the p-type semiconductor region 36 are formed.
Although the shape of the photoelectric conversion part 2 is not specifically limited, For example, it can be set as a square shape.
The photoelectric conversion unit 2 is not particularly limited as long as it can separate charges by incident light and generates an electromotive force. For example, the photoelectric conversion unit using a silicon-based semiconductor or the photoelectric conversion unit using a compound semiconductor A photoelectric conversion part using a dye sensitizer, a photoelectric conversion part using an organic thin film, and the like.

  When either one of the first gas and the second gas is hydrogen gas and the other is oxygen gas, the photoelectric conversion unit 2 receives the light so that the first electrolysis electrode 8 and the second electrolysis electrode 7, it is necessary to use a material that generates an electromotive force necessary for generating hydrogen gas and oxygen gas. The potential difference between the first electrolysis electrode 8 and the second electrolysis electrode 7 needs to be larger than the theoretical voltage (1.23 V) for water decomposition, and for this purpose, a sufficiently large potential difference needs to be generated in the photoelectric conversion unit 2. There is. Therefore, it is preferable that the photoelectric conversion unit 2 connects two or more junctions in series such as a pn junction to generate an electromotive force. For example, the photoelectric conversion layers provided side by side as shown in FIGS. 12 and 14 can be connected in series by the fourth conductive portion 33.

  Examples of the material that performs photoelectric conversion include silicon-based semiconductors, compound semiconductors, and materials based on organic materials, and any photoelectric conversion material can be used. In order to increase the electromotive force, these photoelectric conversion materials can be stacked. In the case of stacking, it is possible to form a multi-junction structure with the same material, but stacking multiple photoelectric conversion layers with different optical band gaps and complementing the low sensitivity wavelength region of each photoelectric conversion layer mutually By doing so, incident light can be efficiently absorbed over a wide wavelength region. The plurality of photoelectric conversion layers preferably have different band gaps. According to such a configuration, the electromotive force generated in the photoelectric conversion unit 2 can be increased, and the electrolytic solution can be electrolyzed more efficiently.

Moreover, it is possible to interpose a conductor such as a transparent conductive film between the layers in order to improve the serial connection characteristics between the photoelectric conversion layers and to match the photocurrent generated in the photoelectric conversion unit 2. Thereby, it becomes possible to suppress deterioration of the photoelectric conversion unit 2.
An example of the photoelectric conversion unit 2 will be specifically described below. The photoelectric conversion unit 2 may be a combination of these. Moreover, as long as there is no contradiction, the example of the following photoelectric conversion parts 2 can also be made into a photoelectric converting layer.

3-3-1. Photoelectric conversion part using a silicon-based semiconductor Examples of the photoelectric conversion part 2 using a silicon-based semiconductor include a single crystal type, a polycrystalline type, an amorphous type, a spherical silicon type, and combinations thereof. Any of them can have a pn junction in which a p-type semiconductor and an n-type semiconductor are joined. Further, a pin junction in which an i-type semiconductor is provided between a p-type semiconductor and an n-type semiconductor may be provided. Further, it may have a plurality of pn junctions, a plurality of pin junctions, or a pn junction and a pin junction.
The silicon-based semiconductor is a semiconductor containing silicon, such as silicon, silicon carbide, or silicon germanium. In addition, silicon or the like in which n-type impurities or p-type impurities are added is included, and crystalline, amorphous, or microcrystalline silicon is also included.
In addition, the photoelectric conversion unit 2 using a silicon-based semiconductor may be a thin film or a thick photoelectric conversion layer formed on the translucent substrate 1, or a pn junction or a wafer such as a silicon wafer. A pin junction may be formed, or a thin film photoelectric conversion layer may be formed on a wafer having a pn junction or a pin junction.

An example of forming the photoelectric conversion unit 2 using a silicon-based semiconductor is shown below.
A first conductivity type semiconductor layer is formed on the first electrode 4 laminated on the translucent substrate 1 by a method such as a plasma CVD method. As the first conductive type semiconductor layer, a p ⁺ type or n ⁺ type amorphous Si thin film doped with a conductivity type determining impurity atom concentration of about 1 × 10 ^{18 to} 5 × 10 ²¹ / cm ³ , or many A crystalline or microcrystalline Si thin film is used. The material of the first conductivity type semiconductor layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x .

On the first conductivity type semiconductor layer thus formed, a polycrystalline or microcrystalline crystalline Si thin film is formed as a crystalline Si photoactive layer by a method such as plasma CVD. The conductivity type is the first conductivity type having a lower doping concentration than the first conductivity type semiconductor, or the i conductivity type. The material for the crystalline Si-based photoactive layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x .

Next, in order to form a semiconductor junction on the crystalline Si-based photoactive layer, a second conductivity type semiconductor layer having a conductivity type opposite to the first conductivity type semiconductor layer is formed by a method such as plasma CVD. As the second conductive type semiconductor layer, an n ⁺ type or p ⁺ type amorphous Si thin film doped with about 1 × 10 ^{18 to} 5 × 10 ²¹ / cm ³ of a conductivity type determining impurity atom, or polycrystalline Alternatively, a microcrystalline Si thin film is used. The material of the second conductivity type semiconductor layer is not limited to Si, and it is also possible to use a compound such as SiC, SiGe, or Si _x O _1-x . In order to further improve the bonding characteristics, it is possible to insert a substantially i-type non-single-crystal Si-based thin film between the crystalline Si-based photoactive layer and the second conductive type semiconductor layer. In this manner, one photoelectric conversion layer closest to the light receiving surface can be stacked.

  Subsequently, a second photoelectric conversion layer is formed. The second photoelectric conversion layer is composed of a first conductivity type semiconductor layer, a crystalline Si-based photoactive layer, and a second conductivity type semiconductor layer, each layer corresponding to the first photoelectric conversion layer. The first conductive type semiconductor layer, the crystalline Si-based photoactive layer, and the second conductive type semiconductor layer are formed. When a potential sufficient for water splitting cannot be obtained with a two-layer tandem, it is preferable to take a three-layer structure or more. However, the volume crystallization fraction of the crystalline Si photoactive layer of the second photoelectric conversion layer is preferably higher than that of the first crystalline Si photoactive layer. Similarly, when three or more layers are laminated, it is preferable to increase the volume crystallization fraction as compared with the lower layer. This increases the absorption in the long wavelength region, shifts the spectral sensitivity to the long wavelength side, and can improve the sensitivity in a wide wavelength region even when the photoactive layer is configured using the same Si material. It is because it becomes. That is, by using a tandem structure with Si having different crystallization rates, the spectral sensitivity is widened, and light can be used with high efficiency. At this time, if the low crystallization rate material is not on the light receiving surface side, high efficiency cannot be achieved. Further, when the crystallization rate is lowered to 40% or less, the amorphous component increases and deterioration occurs.

Next, the example of formation of the photoelectric conversion part 2 using a silicon substrate is shown below.
As the silicon substrate, a single crystal silicon substrate, a polycrystalline silicon substrate, or the like can be used, and may be p-type, n-type, or i-type. An n-type semiconductor portion 37 is formed by doping an n-type impurity such as P into a part of the silicon substrate by thermal diffusion or ion implantation, and a p-type impurity such as B is heated on the other part of the silicon substrate. The p-type semiconductor portion 36 can be formed by doping by diffusion or ion implantation. Thus, pn junction in the silicon substrate, pin junction can be formed and npp ⁺ junction or pnn ⁺ junction, it is possible to form a photoelectric conversion unit 2.

Each of the n-type semiconductor portion 37 and the p-type semiconductor portion 36 can form one region on the silicon substrate as shown in FIGS. 13 and 14, and either of the n-type semiconductor region 37 and the p-type semiconductor region 36 can be formed. A plurality of these can be formed. Alternatively, as shown in FIG. 13, the photoelectric conversion unit 2 can be formed by arranging and arranging silicon substrates on which the n-type semiconductor region 37 and the p-type semiconductor region 36 are arranged and connecting them in series by the fourth conductive unit 33.
Note that, although described with reference to a silicon substrate, pn junction, pin junction, may use other semiconductor substrate or the like can be formed npp ⁺ junction or pnn ⁺ junction. In addition, as long as the n-type semiconductor portion 37 and the p-type semiconductor portion 36 can be formed, the semiconductor layer is not limited to the semiconductor substrate, and may be a semiconductor layer formed on the substrate.

3-3-2. Photoelectric conversion part using compound semiconductor The photoelectric conversion part using a compound semiconductor is, for example, GaP, GaAs, InP, InAs, or IId-VI group elements composed of III-V group elements, CdTe / CdS, Examples thereof include those in which a pn junction is formed using CIGS (Copper Indium Gallium DiSelenide) composed of a group I-III-VI.

An example of a method for manufacturing a photoelectric conversion unit using a compound semiconductor is shown below. In this manufacturing method, all film-forming processes are continuously performed using a metal organic chemical vapor deposition (MOCVD) apparatus. Done. As a group III element material, for example, an organic metal such as trimethylgallium, trimethylaluminum, or trimethylindium is supplied to the growth apparatus using hydrogen gas as a carrier gas. For example, a gas such as arsine (AsH ₃ ), phosphine (PH ₃ ), and stibine (SbH ₃ ) is used as the material of the group V element. As a dopant of p-type impurities or n-type impurities, for example, diethyl zinc for p-type conversion, monosilane (SiH ₄ ), disilane (Si ₂ H ₆ ), hydrogen selenide (H ₂ Se) for n-type conversion. Etc. are used. These source gases can be thermally decomposed by supplying them onto a substrate heated to, for example, 700 ° C., and a desired compound semiconductor material film can be epitaxially grown. The composition of these growth layers can be controlled by the gas composition to be introduced, and the film thickness can be controlled by the gas introduction time. When multi-junction laminating these photoelectric conversion parts, it is possible to form a growth layer with excellent crystallinity by adjusting the lattice constant between layers as much as possible, and to improve the photoelectric conversion efficiency. Become.

  In addition to the portion where the pn junction is formed, for example, a known window layer on the light receiving surface side or a known electric field layer on the non-light receiving surface side may be provided to improve carrier collection efficiency. Further, a buffer layer for preventing diffusion of impurities may be provided.

3-3-3. Photoelectric conversion part using a dye sensitizer The photoelectric conversion part using a dye sensitizer is mainly composed of, for example, a porous semiconductor, a dye sensitizer, an electrolyte, a solvent, and the like.
As a material constituting the porous semiconductor, for example, one or more kinds of known semiconductors such as titanium oxide, tungsten oxide, zinc oxide, barium titanate, strontium titanate, cadmium sulfide can be selected. As a method for forming a porous semiconductor on a substrate, a paste containing semiconductor particles is applied by a screen printing method, an ink jet method and the like, dried or baked, a method of forming a film by a CVD method using a raw material gas, etc. , PVD method, vapor deposition method, sputtering method, sol-gel method, method using electrochemical oxidation-reduction reaction, and the like.

  As the dye sensitizer adsorbed on the porous semiconductor, various dyes having absorption in the visible light region and the infrared light region can be used. Here, in order to firmly adsorb the dye to the porous semiconductor, the carboxylic acid group, carboxylic anhydride group, alkoxy group, sulfonic acid group, hydroxyl group, hydroxylalkyl group, ester group, mercapto group, phosphonyl in the dye molecule It is preferable that a group or the like is present. These functional groups provide an electrical bond that facilitates electron transfer between the excited state dye and the conduction band of the porous semiconductor.

  Examples of dyes containing these functional groups include ruthenium bipyridine dyes, quinone dyes, quinone imine dyes, azo dyes, quinacridone dyes, squarylium dyes, cyanine dyes, merocyanine dyes, and triphenylmethane dyes. Xanthene dyes, porphyrin dyes, phthalocyanine dyes, berylene dyes, indigo dyes, naphthalocyanine dyes, and the like.

  Examples of the method for adsorbing the dye to the porous semiconductor include a method in which the porous semiconductor is immersed in a solution in which the dye is dissolved (dye adsorption solution). The solvent used in the dye adsorption solution is not particularly limited as long as it dissolves the dye, and specifically, alcohols such as ethanol and methanol, ketones such as acetone, ethers such as diethyl ether and tetrahydrofuran. Nitrogen compounds such as acetonitrile, aliphatic hydrocarbons such as hexane, aromatic hydrocarbons such as benzene, esters such as ethyl acetate, water, and the like.

The electrolyte is composed of a redox pair and a solid medium such as a liquid or polymer gel holding the redox pair.
In general, iron- and cobalt-based metals and halogen substances such as chlorine, bromine, and iodine are preferably used as the redox pair, and metal iodides such as lithium iodide, sodium iodide, and potassium iodide and iodine are used. The combination of is preferably used. Furthermore, imidazole salts such as dimethylpropylimidazole iodide can also be mixed.

  Examples of the solvent include carbonate compounds such as propylene carbonate, nitrile compounds such as acetonitrile, alcohols such as ethanol and methanol, water, aprotic polar substances, and the like. Of these, carbonate compounds and nitrile compounds are preferred. Used.

3-3-4. Photoelectric conversion part using organic thin film Photoelectric conversion part 2 using an organic thin film is an electron hole transport layer composed of an organic semiconductor material having electron donating properties and electron accepting properties, or an electron transport layer having electron accepting properties. And a hole transport layer having an electron donating property may be laminated.
The electron-donating organic semiconductor material is not particularly limited as long as it has a function as an electron donor, but it is preferable that a film can be formed by a coating method, and among them, an electron-donating conductive polymer is preferably used. The

  Here, the conductive polymer means a π-conjugated polymer, which is composed of a π-conjugated system in which double bonds or triple bonds containing carbon-carbon or hetero atoms are alternately linked to single bonds, and exhibits semiconducting properties. Point.

  Examples of the electron-donating conductive polymer material include polyphenylene, polyphenylene vinylene, polythiophene, polycarbazole, polyvinyl carbazole, polysilane, polyacetylene, polypyrrole, polyaniline, polyfluorene, polyvinyl pyrene, polyvinyl anthracene, and derivatives, Examples thereof include a polymer, a phthalocyanine-containing polymer, a carbazole-containing polymer, and an organometallic polymer. Among these, thiophene-fluorene copolymer, polyalkylthiophene, phenyleneethynylene-phenylene vinylene copolymer, fluorene-phenylene vinylene copolymer, thiophene-phenylene vinylene copolymer, and the like are preferably used.

The electron-accepting organic semiconductor material is not particularly limited as long as it has a function as an electron acceptor. However, it is preferable that a film can be formed by a coating method, and among them, an electron-donating conductive polymer is preferably used. The
Examples of the electron-accepting conductive polymer include polyphenylene vinylene, polyfluorene, and derivatives and copolymers thereof, or carbon nanotubes, fullerene and derivatives thereof, CN group or CF ₃ group-containing polymers, and -CF thereof. Examples thereof include _3- substituted polymers.

In addition, an electron-accepting organic semiconductor material doped with an electron-donating compound, an electron-donating organic semiconductor material doped with an electron-accepting compound, or the like can be used. Examples of the electron-accepting conductive polymer material doped with the electron-donating compound include the above-described electron-accepting conductive polymer material. As the electron-donating compound to be doped, for example, a Lewis base such as an alkali metal such as Li, K, Ca, or Cs or an alkaline earth metal can be used. The Lewis base acts as an electron donor. Examples of the electron-donating conductive polymer material doped with the electron-accepting compound include the above-described electron-donating conductive polymer material. As the electron-accepting compound to be doped, for example, a Lewis acid such as FeCl ₃ , AlCl ₃ , AlBr ₃ , AsF ₆ or a halogen compound can be used. In addition, Lewis acid acts as an electron acceptor.

3-4. Second Electrode The second electrode 5 can be provided on the back surface of the photoelectric conversion unit 2. The second electrode 5 can also be provided between the back surface of the photoelectric conversion unit 2 and the first electrolysis electrode 8 and between the back surface of the photoelectric conversion unit 2 and the insulating unit 11. The second electrode 5 can be electrically connected to the first electrolysis electrode 8. By providing the second electrode 5, it is possible to reduce ohmic cross between the back surface of the photoelectric conversion unit 2 and the first electrolysis electrode 8. The second electrode 5 may be in contact with the first electrolysis electrode 8. Further, the second electrode 5 may be electrically connected to the first electrolysis electrode 8 via the switching unit 29 and the wiring 50.
Moreover, it is preferable that the 2nd electrode 5 has the corrosion resistance with respect to electrolyte solution, and the liquid shielding property with respect to electrolyte solution. Thereby, corrosion of the photoelectric conversion part 2 by electrolyte solution can be prevented.
Although it will not specifically limit if the 2nd electrode 5 has electroconductivity, For example, it is a metal thin film, for example, is thin films, such as Al, Ag, Au. These can be formed by, for example, sputtering. Further, for example, a transparent conductive film such as In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, and SnO ₂ is used.

3-5. First Conductive Part The first conductive part 9 can be provided in contact with the first electrode 4 and the second electrolysis electrode 7. By providing the first conductive portion 9, the first electrode 4 and the second electrolysis electrode 7 in contact with the light receiving surface of the photoelectric conversion portion 2 can be easily electrically connected.
Moreover, the 1st electroconductive part 9 may be provided in the contact hole which penetrates the photoelectric conversion part 2 like FIG. Thus, the current path between the light receiving surface of the photoelectric conversion unit 2 and the second electrolysis electrode 7 can be shortened, and the first gas and the second gas can be generated more efficiently. Moreover, the contact hole provided with the 1st electroconductive part 9 may have one or more, and may have a circular cross section.
Moreover, the 1st electroconductive part 9 may be provided so that the side surface of the photoelectric conversion part 2 may be covered like FIG.

  The material of the 1st electroconductive part 9 will not be restrict | limited especially if it has electroconductivity. A paste containing conductive particles, for example, a carbon paste, an Ag paste or the like applied by screen printing, an inkjet method, etc., dried or baked, a method of forming a film by a CVD method using a raw material gas, a PVD method, Examples thereof include a vapor deposition method, a sputtering method, a sol-gel method, and a method using an electrochemical redox reaction.

3-6. Insulating part The insulating part 11 can be provided in order to prevent the occurrence of leakage current. For example, when providing the 1st electroconductive part 9 in the contact hole which penetrates the photoelectric conversion part 2 like FIG. 6, 9, the insulating part 11 can be provided in the side wall of a contact hole.
Moreover, the insulation part 11 can be provided between the electrode 7 for 2nd electrolysis and the back surface of the photoelectric conversion part 2 like FIG. This can prevent a leak current from being generated between the second electrolysis electrode 7 and the back surface of the photoelectric conversion unit 2. When the photoelectric conversion unit 2 receives light as shown in FIGS. 13 and 14 to generate a potential difference between the first area and the second area on the back surface of the photoelectric conversion unit 2, 1 between the electrode 8 for electrolysis and the back surface of the photoelectric conversion unit 2, and between the second electrode for electrolysis 7 and the back surface of the photoelectric conversion unit 2. You may have an opening on it. Thereby, the electrons and holes formed by the photoelectric conversion unit 2 receiving light can be efficiently separated, and the photoelectric conversion efficiency can be further increased.
Moreover, it is preferable that the insulation part 11 has the corrosion resistance with respect to electrolyte solution, and the liquid shielding property with respect to electrolyte solution. Thereby, generation | occurrence | production of a leakage current can be prevented and corrosion of the photoelectric conversion part 2 by electrolyte solution can be prevented.

The insulating part 11 can be used regardless of an organic material or an inorganic material. For example, polyamide, polyimide, polyarylene, aromatic vinyl compound, fluorine polymer, acrylic polymer, vinylamide polymer, etc. Examples of organic polymers and inorganic materials include metal oxides such as Al ₂ O ₃ , SiO ₂ such as porous silica films, fluorine-added silicon oxide films (FSG), SiOC, HSQ (Hydrogen Silsesquioxane) films, SiN _x , It is possible to use a method of forming a film by dissolving silanol (Si (OH) ₄ ) in a solvent such as alcohol and applying and heating.

  As a method for forming the insulating portion 11, a film containing a paste containing an insulating material is applied by a screen printing method, an ink jet method, a spin coating method, etc., dried or baked, or a CVD method using a source gas is used. And a method using a PVD method, a vapor deposition method, a sputtering method, a sol-gel method, and the like.

3-7. Second conductive part, third conductive part, fourth conductive part The second conductive part 24 and the third conductive part 25 are provided between the insulating part 11 and the second electrolysis electrode 7 or between the insulating part 11 and the first electrolytic part. It can be provided between the electrodes 8 for use. By providing the second conductive portion 24 and the third conductive portion 25, the electromotive force generated by the photoelectric conversion portion 2 receiving light can be efficiently output to the first electrolysis electrode 8 or the second electrolysis electrode 7. It is possible to reduce ohmic cross. The 2nd conductive part 24 and the 3rd conductive part 25 can be provided as shown in Drawings 12-14, for example.
The second conductive part 24 and the third conductive part 25 preferably have corrosion resistance against the electrolytic solution and liquid shielding properties against the electrolytic solution. Thereby, an increase in ohmic resistance can be prevented, and corrosion of the photoelectric conversion unit 2 due to the electrolytic solution can be prevented.
The 4th electroconductive part 33 can be provided so that a photoelectric converting layer may be connected in series like FIG.

The second conductive portion 24, the third conductive portion 25, or the fourth conductive portion 33 is not particularly limited as long as it has conductivity. For example, the second conductive portion 24, the third conductive portion 25, or the fourth conductive portion 33 is a metal thin film. is there. These can be formed by, for example, sputtering. Further, for example, a transparent conductive film such as In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, and SnO ₂ is used.

3-8. First Electrolysis Electrode, Second Electrolysis Electrode The first electrolysis electrode 8 and the second electrolysis electrode 7 are respectively provided on the back surface of the photoelectric conversion unit 2. Moreover, the electrode 8 for 1st electrolysis and the electrode 7 for 2nd electrolysis can each have the surface of the back surface side of the photoelectric conversion part 2, and the surface which is the back surface and can contact electrolyte solution. Thus, the first electrolysis electrode 8 and the second electrolysis electrode 7 do not block light incident on the photoelectric conversion unit 2.
In addition, when the first electrolysis electrode 8 and the second electrolysis electrode 7 are in contact with the electrolytic solution, the electrolysis solution is electrolyzed by using the electromotive force generated by the photoelectric conversion unit 2 receiving light, and the first gas is obtained. And the second gas can be generated. For example, when an electromotive force is generated between the light receiving surface and the back surface when the photoelectric conversion unit 2 receives light, the first electrolysis electrode 8 is electrically connected to the back surface of the photoelectric conversion unit 2 as shown in FIGS. The second electrolysis electrode 7 can be electrically connected to the light receiving surface of the photoelectric conversion unit 2. Further, when an electromotive force is generated between the first area and the second area on the back surface when the photoelectric conversion unit 2 receives light, the first electrolysis electrode 8 is connected to the first area and the second area as shown in FIGS. The second electrolysis electrode 7 can be electrically connected to the other of the first area and the second area.

  9 and 10, when the first electrolysis electrode 8 is not in contact with the back surface of the photoelectric conversion unit 2 or the second electrode 5, the first electrolysis electrode 8 is connected to the photoelectric conversion unit 2 via the switching unit 29. It can be electrically connected to the back surface of. 8 and 10, the second electrolysis electrode 7 can be electrically connected to the light receiving surface of the photoelectric conversion unit 2 via the switching unit 29.

At least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 may be plural, and each may have a surface that can contact the strip-shaped electrolyte solution, and the long sides of the surfaces are adjacent to each other. Alternatively, they may be provided alternately. In this way, by providing the first electrolysis electrode 8 and the second electrolysis electrode 7, the distance between the portion where the reaction generating the first gas occurs and the portion where the reaction generating the second gas occurs is increased. It can be shortened, and the ion concentration imbalance generated in the electrolyte can be reduced. Moreover, the 1st gas and 2nd gas can be collect | recovered easily by making the surface which can contact electrolyte solution into strip | belt shape.
The first electrolysis electrode 8 and the second electrolysis electrode 7 preferably have corrosion resistance to the electrolytic solution and liquid shielding properties to the electrolytic solution. Thereby, the first gas and the second gas can be stably generated, and corrosion of the photoelectric conversion unit 2 due to the electrolytic solution can be prevented. For example, a metal plate or a metal film having corrosion resistance against the electrolytic solution can be used for the first electrolysis electrode 8 and the second electrolysis electrode 7.

Moreover, it is preferable that at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 has a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. According to such a configuration, the first gas or the second gas can be generated more efficiently by the electromotive force generated in the photoelectric conversion unit 2.
In addition, at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 is preferably a porous conductor carrying a catalyst. According to such a configuration, the surface area of at least one of the first electrolysis electrode 8 and the second electrolysis electrode 7 can be increased, and the first gas or the second gas can be generated more efficiently. Can do. Further, by using a porous conductor, it is possible to suppress a change in potential due to a current flowing between the photoelectric conversion unit 2 and the catalyst, and to generate the first gas or the second gas more efficiently. Can be made. In this case, the first electrolysis electrode 8 or the second electrolysis electrode 7 can also have a two-layer structure of a portion having a liquid shielding property against the electrolytic solution and a porous portion.
One of the first electrolysis electrode 8 and the second electrolysis electrode 7 may be a hydrogen generation unit, and the other may be an oxygen generation unit. In this case, one of the first gas and the second gas is hydrogen gas, and the other is oxygen gas.

3-9. Hydrogen generating part The hydrogen generating part is a part for generating H ₂ from the electrolytic solution, and is one of the first electrolysis electrode 8 and the second electrolysis electrode 7.
Further, the hydrogen generation unit may include a catalyst for a reaction in which H ₂ is generated from the electrolytic solution. Thereby, the reaction rate of the reaction in which H ₂ is generated from the electrolytic solution can be increased. The hydrogen generation part may consist only of a catalyst for the reaction in which H ₂ is generated from the electrolytic solution, or this catalyst may be supported on a support. Further, the hydrogen generation unit may have a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. Thereby, the reaction in which H ₂ is generated from the electrolytic solution can be set to a faster reaction rate. The hydrogen generation part may be a porous conductor carrying a catalyst. This can increase the catalyst surface area. In addition, a change in potential due to a current flowing between the light receiving surface or the back surface of the photoelectric conversion unit 2 and the catalyst included in the hydrogen generation unit can be suppressed. Furthermore, the hydrogen generation unit may include a hydrogen generation catalyst, and the hydrogen generation catalyst may include at least one of Pt, Ir, Ru, Pd, Rh, Au, Fe, Ni, and Se. According to such a configuration, hydrogen gas can be generated at a higher reaction rate by the electromotive force generated in the photoelectric conversion unit 2.

The catalyst for the reaction of generating H ₂ from the electrolyte (hydrogen generation catalyst) is a catalyst that promotes the conversion of two protons and two electrons into one molecule of hydrogen, is chemically stable, and generates hydrogen overvoltage. Can be used. For example, platinum group metals such as Pt, Ir, Ru, Pd, Rh, and Au, which have catalytic activity for hydrogen, and alloys or compounds thereof, Fe, Ni, and Se that constitute the active center of hydrogenase that is a hydrogen-producing enzyme. An alloy or a compound, a combination thereof, or the like can be preferably used. Among them, a nanostructure containing Pt and Pt has a small hydrogen generation overvoltage and can be suitably used. Materials such as CdS, CdSe, ZnS, and ZrO ₂ whose hydrogen generation reaction is confirmed by light irradiation can also be used.

The hydrogen generating catalyst can be supported on the conductor. Examples of the conductor carrying the catalyst include metal materials, carbonaceous materials, and conductive inorganic materials.
As the metal material, a material having electronic conductivity and resistance to corrosion in an acidic atmosphere is preferable. Specifically, noble metals such as Au, Pt, Pd, metals such as Ti, Ta, W, Nb, Ni, Al, Cr, Ag, Cu, Zn, Su, Si, and nitrides and carbides of these metals, Examples of the alloy include stainless steel, Cu—Cr, Ni—Cr, and Ti—Pt. It is more preferable that the metal material contains at least one element selected from the group consisting of Pt, Ti, Au, Ag, Cu, Ni, and W from the viewpoint that there are few other chemical side reactions. These metal materials have a relatively small electric resistance, and can suppress a decrease in voltage even when a current is extracted in the surface direction. Further, when using a metal material having poor corrosion resistance in an acidic atmosphere such as Cu, Ag, Zn, etc., noble metals and metals having corrosion resistance such as Au, Pt, Pd, carbon, graphite, glassy carbon, A metal surface having poor corrosion resistance may be coated with a conductive polymer, a conductive nitride, a conductive carbide, a conductive oxide, or the like.

  As the carbonaceous material, a chemically stable and conductive material is preferable. Examples thereof include carbon powders and carbon fibers such as acetylene black, vulcan, ketjen black, furnace black, VGCF, carbon nanotube, carbon nanohorn, and fullerene.

Examples of the inorganic material having conductivity include In—Zn—O (IZO), In—Sn—O (ITO), ZnO—Al, Zn—Sn—O, SnO ₂ , and antimony oxide-doped tin oxide. .

  In addition, examples of the conductive polymer include polyacetylene, polythiophene, polyaniline, polypyrrole, polyparaphenylene, polyparaphenylene vinylene, and the like, and examples of the conductive nitride include carbon nitride, silicon nitride, gallium nitride, indium nitride, and nitride. Germanium, titanium nitride, zirconium nitride, thallium nitride, etc. are listed, and conductive carbides include tantalum carbide, silicon carbide, zirconium carbide, titanium carbide, molybdenum carbide, niobium carbide, iron carbide, nickel carbide, hafnium carbide, tungsten carbide. , Vanadium carbide, chromium carbide, and the like. Examples of the conductive oxide include tin oxide, indium tin oxide (ITO), and antimony oxide-doped tin oxide.

  The structure of the conductor supporting the hydrogen generation catalyst includes a plate shape, a foil shape, a rod shape, a mesh shape, a lath plate shape, a porous plate shape, a porous rod shape, a woven fabric shape, a nonwoven fabric shape, a fiber shape, and a felt shape. It can be used suitably. Further, a grooved conductor in which the surface of the felt-like electrode is pressure-bonded in a groove shape is preferable because the electric resistance and the flow resistance of the electrode liquid can be reduced.

3-10. Oxygen generating portion The oxygen generating portion is a portion that generates O ₂ from the electrolytic solution, and is one of the first electrolysis electrode 8 and the second electrolysis electrode 7.
Further, the oxygen generation unit may include a catalyst for a reaction in which O ₂ is generated from the electrolytic solution. Thereby, the reaction rate of the reaction in which O ₂ is generated from the electrolytic solution can be increased. Further, the oxygen generation part may consist only of a catalyst for the reaction that generates O ₂ from the electrolytic solution, or the catalyst may be supported on a carrier. Further, the oxygen generation unit may have a catalyst surface area larger than the area of the light receiving surface of the photoelectric conversion unit 2. Thereby, the reaction in which O ₂ is generated from the electrolytic solution can be set to a faster reaction rate. The oxygen generation part may be a porous conductor carrying a catalyst. This can increase the catalyst surface area. In addition, a change in potential due to a current flowing between the light receiving surface or the back surface of the photoelectric conversion unit 2 and the catalyst included in the oxygen generation unit can be suppressed. Furthermore, the oxygen generation unit may include an oxygen generation catalyst, and the oxygen generation catalyst may include at least one of Mn, Ca, Zn, Co, and Ir. According to such a configuration, oxygen gas can be generated at a higher reaction rate by the electromotive force generated in the photoelectric conversion unit.

The catalyst for the reaction of generating O ₂ from the electrolyte (oxygen generating catalyst) is a catalyst that promotes the conversion of two water molecules into one molecule of oxygen, four protons, and four electrons, and is chemically stable. In addition, a material having a small oxygen generation overvoltage can be used. For example, oxides or compounds containing Mn, Ca, Zn, Co, which are active centers of Photosystem II, which is an enzyme that catalyzes the reaction of generating oxygen from water using light, and platinum such as Pt, RuO ₂ , IrO ₂ It is possible to use compounds containing group metals, oxides or compounds containing transition metals such as Ti, Zr, Nb, Ta, W, Ce, Fe, Ni, and combinations of the above materials. Among these, iridium oxide, manganese oxide, cobalt oxide, and cobalt phosphate can be suitably used because they have low overvoltage and high oxygen generation efficiency.

The oxygen generating catalyst can be supported on the conductor. Examples of the conductor carrying the catalyst include metal materials, carbonaceous materials, and conductive inorganic materials. These explanations apply as long as there is no contradiction in the explanation of the hydrogen generation catalyst described in “3-9. Hydrogen generation section”.
When the catalytic activity of the hydrogen generating catalyst and the oxygen generating catalyst alone is small, a promoter can be used. Examples thereof include oxides or compounds of Ni, Cr, Rh, Mo, Co, and Se.

  The method for supporting the hydrogen generating catalyst and the oxygen generating catalyst can be applied directly to a conductor or semiconductor, PVD methods such as vacuum deposition, sputtering, and ion plating, dry coating methods such as CVD, The method can be appropriately changed depending on the material such as an analysis method. A conductive material can be appropriately supported between the photoelectric conversion unit and the catalyst. Also, when the catalytic activity for hydrogen generation and oxygen generation is not sufficient, the reaction surface area is increased by supporting it on porous materials such as metals and carbon, fibrous materials, nanoparticles, etc., and the hydrogen and oxygen generation rates are improved. It is possible to make it.

3-11. Back Substrate The back substrate 14 can be provided on the first electrolysis electrode 8 and the second electrolysis electrode 7 so as to face the translucent substrate 1.
The back substrate 14 can be provided such that a space is provided between the first electrolysis electrode 8 and the second electrolysis electrode 7 and the back substrate 14. This space can be used as the electrolytic solution chamber 15, and the first electrolytic electrode 8 and the second electrolytic electrode 7 can be brought into contact with the electrolytic solution by introducing the electrolytic solution into the electrolytic solution chamber 15. Moreover, when using a box-shaped thing for the back substrate 14, the back substrate 14 may be the bottom part of a box.

  Further, the back substrate 14 is a material that constitutes the electrolyte chamber 15 and confines the generated first gas and second gas, and a highly confidential substance is required. It is not particularly limited whether it is transparent or opaque, but it is preferably a transparent material in that it can be visually confirmed that the first gas and the second gas are generated. . The transparent back substrate is not particularly limited, and examples thereof include a transparent rigid material such as quartz glass, Pyrex (registered trademark), and a synthetic quartz plate, a transparent resin plate, and a transparent resin film. Among them, it is preferable to use a glass material because it is a gas that is not chemically permeable and is chemically and physically stable.

3-12. The partition wall 13 includes an electrolyte chamber 15 that is a space between the first electrolysis electrode 8 and the back substrate 14 and an electrolyte chamber 15 that is a space between the second electrolysis electrode 7 and the back substrate 14. It can be provided so as to partition. As a result, the first gas and the second gas generated by the first electrolysis electrode 8 and the second electrolysis electrode 7 can be prevented from mixing, and the first gas and the second gas can be separated. It can be recovered.
The partition wall 13 may include an ion exchanger. As a result, the ion concentration that is unbalanced by the electrolytic solution in the space between the first electrolysis electrode 8 and the back substrate 14 and the electrolytic solution in the space between the second electrolysis electrode 7 and the back substrate 14 is reduced. Can be kept constant.

For the partition wall 13, for example, an inorganic film such as porous glass, porous zirconia, or porous alumina or an ion exchanger can be used.
As the ion exchanger, any ion exchanger known in the art can be used, and a proton conductive membrane, a cation exchange membrane, an anion exchange membrane, or the like can be used.
The material of the proton conductive film is not particularly limited as long as it is a material having proton conductivity and electrical insulation, and a polymer film, an inorganic film, or a composite film can be used.

  Examples of the polymer membrane include Nafion (registered trademark) manufactured by DuPont, Aciplex (registered trademark) manufactured by Asahi Kasei Co., and Flemion (registered trademark) manufactured by Asahi Glass Co., Ltd., which are perfluorosulfonic acid electrolyte membranes. Examples thereof include membranes and hydrocarbon electrolyte membranes such as polystyrene sulfonic acid and sulfonated polyether ether ketone.

  Examples of the inorganic film include films made of phosphate glass, cesium hydrogen sulfate, polytungstophosphoric acid, ammonium polyphosphate, and the like. Examples of the composite membrane include a membrane made of a sulfonated polyimide polymer, a composite of an inorganic material such as tungstic acid and an organic material such as polyimide, and specifically, Gore Select membrane (registered trademark) or pores manufactured by Gore. Examples thereof include a filling electrolyte membrane. Furthermore, when used in a high temperature environment (for example, 100 ° C. or higher), sulfonated polyimide, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), sulfonated polybenzimidazole, phosphonated polybenzimidazole, sulfuric acid. Examples include cesium hydrogen and ammonium polyphosphate.

The cation exchange membrane may be any solid polymer electrolyte that can move cations. Specifically, fluorine ion exchange membranes such as perfluorocarbon sulfonic acid membranes and perfluorocarbon carboxylic acid membranes, polybenzimidazole membranes impregnated with phosphoric acid, polystyrene sulfonic acid membranes, sulfonated styrene / vinylbenzene copolymers Examples include membranes.
When the anion transport number of the supporting electrolyte solution is high, it is preferable to use an anion exchange membrane. As the anion exchange membrane, a solid polymer electrolyte capable of transferring anions can be used. Specifically, a polyorthophenylenediamine film, a fluorine-based ion exchange film having an ammonium salt derivative group, a vinylbenzene polymer film having an ammonium salt derivative group, a film obtained by aminating a chloromethylstyrene / vinylbenzene copolymer, etc. Can be mentioned.

3-13. Seal material The seal material 16 is a material for adhering the translucent substrate 1 and the back substrate 14 and sealing the electrolyte in the hydrogen production apparatus 23 and the first gas and the second gas generated in the hydrogen production apparatus 23. It is. When a box-shaped substrate is used for the back substrate 14, a sealing material 16 is used for bonding the box and the translucent substrate 1. As the sealing material 16, for example, an ultraviolet curable adhesive, a thermosetting adhesive, or the like is preferably used, but the type thereof is not limited. The UV curable adhesive is a resin that undergoes polymerization upon irradiation with light having a wavelength of 200 to 400 nm and undergoes a curing reaction within a few seconds after light irradiation, and is divided into a radical polymerization type and a cationic polymerization type. Examples of the polymerization type resin include acrylates, unsaturated polyesters, and examples of the cationic polymerization type include epoxy, oxetane, and vinyl ether. Examples of the thermosetting polymer adhesive include organic resins such as phenol resin, epoxy resin, melamine resin, urea resin, and thermosetting polyimide. The thermosetting polymer adhesive is heated and polymerized in a state where pressure is applied at the time of thermocompression bonding, and then cooled to room temperature while being pressurized. I don't need it. In addition to the organic resin, a hybrid material having high adhesion to the glass substrate can be used. By using a hybrid material, mechanical properties such as elastic modulus and hardness are improved, and heat resistance and chemical resistance are dramatically improved. The hybrid material is composed of inorganic colloidal particles and an organic binder resin. For example, what is comprised from inorganic colloidal particles, such as a silica, and organic binder resin, such as an epoxy resin, a polyurethane acrylate resin, and a polyester acrylate resin, is mentioned.

  Here, the sealing material 16 is described. However, the sealing material 16 is not limited as long as it has a function of adhering the translucent substrate 1 and the back substrate 14, and a member such as a screw is externally used using a resin or metal gasket. It is also possible to appropriately use a method of applying pressure physically to increase confidentiality.

3-14. Electrolyte Chamber The electrolyte chamber 15 can be a space between the first electrolysis electrode 8 and the back substrate 14 and a space between the second electrolysis electrode 7 and the back substrate 14. Further, the electrolyte chamber 15 can be partitioned by the partition wall 13.

3-15. Water Supply Port The water supply port 18 can be provided by making an opening in a part of the sealing material 16 included in the hydrogen production apparatus 23 or a part of the back substrate 14. The water supply port 18 is arranged to replenish the electrolytic solution that has been decomposed into the first gas and the second gas, and the location and shape of the water supply port 18 can even supply the electrolytic solution as a raw material to the hydrogen production device 23 efficiently. If it does, it will not be limited in particular.

3-16. 1st gas exhaust port, 2nd gas exhaust port The 1st gas exhaust port 20 and the 2nd gas exhaust port 19 are adjoining to the edge part of the electrode 8 for 1st electrolysis, and the edge part of the electrode 7 for 2nd electrolysis, respectively. Provided. Thus, the first gas can be recovered from the first gas discharge port 20 and the second gas can be recovered from the second gas discharge port 19.

The first gas outlet 20 is a surface that can contact the electrolyte of the first electrolysis electrode 8 when the hydrogen production device 23 is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane. It can be provided close to the upper end. Further, the second gas discharge port 19 is a surface that can contact the electrolytic solution of the second electrolysis electrode 7 when the hydrogen production device 23 is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane. It can be provided close to the upper end. Thus, when the hydrogen production device 23 is installed so that the light receiving surface of the photoelectric conversion unit 2 is inclined with respect to the horizontal plane, and sunlight is incident on the light receiving surface, the hydrogen generating device 23 is generated at the first electrolysis electrode 8. The first gas can be raised as bubbles in the electrolyte solution and recovered from the first gas discharge port 20, and the second gas generated at the second electrolysis electrode 7 can be raised as bubbles in the electrolyte solution to be second. It can be recovered from the gas outlet 19.
The 1st gas exhaust port 20 and the 2nd gas exhaust port 19 can be formed by providing opening in the sealing material 16, for example. An inflow prevention valve may be provided so that the electrolyte does not flow into the first gas outlet 20 and the second gas outlet 19.

  Moreover, the 1st gas exhaust port 20 can be connected with a 1st gas exhaust path, and the 2nd gas exhaust port 19 can be connected with a 2nd gas exhaust path. In addition, the first gas discharge path can be connected to the plurality of first gas discharge ports 20, and the second gas discharge path can be connected to the plurality of second gas discharge ports 19. Thereby, the first gas and the second gas generated in the hydrogen production apparatus 23 can be recovered. Further, the first gas discharge path or the second gas discharge path can be connected to the hydrogen storage unit 12. As a result, the hydrogen gas generated by the hydrogen production device 23 can be stored in the hydrogen storage unit 12. One of the first gas discharge path and the second gas discharge path can constitute a hydrogen flow path, and the other can constitute an air flow path.

3-17. Electrolytic Solution The electrolytic solution is not particularly limited as long as it is a raw material for the first gas and the second gas. For example, the electrolytic solution is an aqueous solution containing an electrolyte, for example, an electrolytic solution containing 0.1 M H ₂ SO ₄ , 0.1M potassium phosphate buffer. In this case, hydrogen gas and oxygen gas can be produced from the electrolytic solution as the first gas and the second gas.

4). Fuel Cell Unit The fuel cell unit 22 generates electricity using hydrogen gas as fuel and outputs electromotive force to the outside. Further, the fuel cell unit 22 can generate power according to the power demand and the photovoltaic power of the photoelectric conversion unit 2. Thereby, it is possible to suppress a shortage of supply power due to fluctuations in the photoelectric conversion unit 2 and fluctuations in power demand.
FIG. 15 is a schematic cross-sectional view of the fuel cell unit 22 included in the power generation system of the present embodiment.
The fuel cell unit 22 can include a fuel electrode 51, an air electrode 52, and an electrolyte membrane 53 sandwiched between the fuel electrode 51 and the air electrode 52. By supplying hydrogen gas to the fuel electrode 51 and supplying air or oxygen gas to the air electrode 52, an electromotive force can be generated between the fuel electrode 51 and the air electrode 52. The fuel electrode 51 and the air electrode 52 can be electrically connected to an external circuit in order to output an electromotive force to the outside. The fuel electrode 51 and the air electrode 52 can also output an electromotive force to an external circuit via the switching unit 29.

The electrolyte membrane 53 may be an electrolyte membrane that exhibits ionic conductivity in a wet state. Further, the electrolyte membrane 53 may be one in which the ion conductive species is H ⁺ or OH ⁻ .
The fuel cell unit 22 may be a polymer electrolyte fuel cell, for example. In this case, the electrolyte membrane 53 can be a solid polymer membrane, and the electrolyte membrane 53, the fuel electrode 51, and the air electrode 52 can constitute a membrane electrode assembly (MEA).
As the electrolyte membrane 53, for example, an electrolyte membrane containing a perfluorosulfonic acid group polymer can be used. Since such an electrolyte membrane 53 does not exhibit ionic conductivity unless it contains moisture, it is necessary to supply moisture to the electrolyte membrane 53. In addition, the electrolyte membrane 53 that needs moisture in order to exhibit such ionic conductivity needs to maintain an appropriate wet state, and it is necessary to supply moisture to the fuel cell unit 22 appropriately. If the amount of water supplied to the fuel cell unit 22 is too large, the moisture content of the electrolyte membrane 53 increases and the mechanical strength of the electrolyte membrane 53 decreases, or the pores in the fuel electrode 51 or the air electrode 52 are blocked. There are cases where the diffusion of the reaction gas is reduced to reduce the cell voltage (flooding phenomenon). In addition, if the amount of water supplied to the fuel cell unit 22 is too small, the ionic conductivity of the electrolyte membrane 53 may decrease, and the cell voltage may decrease. Therefore, it is necessary to supply moisture to the fuel cell unit 22 so that the electrolyte membrane 53 is maintained in a moderately wet state.

As a method of supplying moisture to the fuel cell unit 22, there is a method of humidifying and supplying hydrogen gas as fuel to the fuel electrode 51. Further, the air (or oxygen gas) supplied to the air electrode 52 may be humidified. According to this method, the amount of water supplied to the fuel cell unit 22 can be controlled by controlling the humidity of hydrogen gas and air (oxygen gas), and water can be appropriately supplied to the fuel cell unit 22. it can.
The hydrogen gas and air (oxygen gas) supplied to the fuel cell unit 22 can be humidified by the humidity control unit 10. The humidification of hydrogen gas and air (oxygen gas) by the humidity control unit 10 will be described later.

The fuel cell unit 22 needs to be at a certain temperature or higher in order to generate power. For example, when the fuel cell unit 22 is a polymer electrolyte fuel cell, the operating temperature is 60 to 100 ° C. Therefore, particularly when the fuel cell unit 22 is started, it is necessary to quickly raise the fuel cell unit 22 to the operating temperature. In addition, the fuel cell unit 22 can have a heating unit to raise the temperature of the fuel cell unit 22.
In addition, after the fuel cell unit 22 starts power generation, hydrogen gas or the like chemically reacts with the fuel electrode 51 and the air electrode 52 to generate reaction heat, and thus the fuel cell unit 22 needs to be cooled. For this reason, the fuel cell unit 22 can include a cooler such as a radiator.

Therefore, in order to quickly start the power generation by the fuel cell unit 22, the fuel cell unit 22 is quickly heated to the operating temperature and the fuel cell unit 53 is maintained in a moderately wet state. It is necessary to quickly supply moisture to 22, supply hydrogen gas to the fuel electrode 51, and supply air (oxygen gas) to the air electrode 52.
The fuel cell unit 22 can be set to the fuel cell power generation preparation mode. Specifically, the fuel cell unit 22 can be raised to a predetermined temperature that is equal to or lower than the operating temperature by a signal from the control unit 17. As a result, when it is desired to output the generated power of the fuel cell unit 22 to the outside, the fuel cell unit 22 can be quickly brought to the operating temperature, and the generated power of the fuel cell unit 22 can be quickly externally manipulated. In addition, the humidity control unit 10 can be set in the fuel cell preparation mode together with the fuel cell unit 22.

The hydrogen gas supplied to the fuel electrode 51 of the fuel cell unit 22 may be hydrogen gas stored in the hydrogen storage unit 12 or hydrogen gas supplied from a hydrogen cylinder. Alternatively, hydrogen gas generated by reforming methanol, gasoline, or city gas may be used.
The air (oxygen gas) supplied to the air electrode 52 of the fuel cell unit 22 may be air or oxygen gas supplied from an air compressor, or may be air or oxygen gas supplied from a cylinder. Well, it may be air taken from outside air.
The fuel cell unit 22 may be connected to the control unit 17 through a signal line as shown in FIG. 1 or may be controlled by a signal from the control unit 17. Further, the fuel cell unit 22 and the control unit 17 may be provided so that signals can be transmitted and received wirelessly.
Furthermore, the fuel cell unit 22 may be provided so as to be able to perform a power load following operation based on information input from the control unit 17.

5. Switching Unit The switching unit 29 can have an electric circuit as shown in FIG. 3 or FIG. Moreover, FIGS. 16-18 is a schematic circuit diagram of the electric power generation system of this embodiment, respectively. In addition, although one switching part 29 is shown in drawing, you may consist of a several switching part 29. FIG.
The switching unit 29 is provided so as to switch between a circuit that outputs the photovoltaic power of the photoelectric conversion unit 2 to the water electrolysis unit 21 and a circuit that outputs the photovoltaic power of the photoelectric conversion unit 2 to the first external circuit. It is done. As a result, the electromotive force generated when the photoelectric conversion unit 2 receives light can be supplied as power to the first external circuit, and water is electrolyzed using the electromotive force generated when the photoelectric conversion unit 2 receives light to generate hydrogen. Gas can be produced.

The switching unit 29 can be electrically connected to the second external circuit, and outputs an electromotive force input from the second external circuit to the first electrolysis electrode 8 and the second electrolysis electrode 7. It is possible to switch to a circuit that generates hydrogen gas and oxygen gas from the electrolyte. Thus, hydrogen gas and oxygen gas can be produced from the electrolyte using the electromotive force input from the second external circuit. For example, hydrogen gas can be produced using midnight power. The method for electrically connecting the switching unit 29 to the second external circuit is not particularly limited. For example, the switching unit 29 may include an input terminal and be electrically connected to the second external circuit via the input terminal. .
The switching unit 29 may be connected to the control unit 17 through a signal line as shown in FIG. The switching unit 29 and the control unit 17 may be provided so that signals can be transmitted and received wirelessly.

For example, when the hydrogen production apparatus 23 has a cross section as shown in FIG. 10 and the power generation system has an electric circuit as shown in FIG. 3, for example, SW (switch) 1 and SW2 are in an ON state, and SW3 and SW4 are In the OFF state, the electromotive force generated by the photoelectric conversion unit 2 receiving light can be output to the first external circuit. In this case, when power is generated by the fuel cell unit 22, both the photovoltaic power of the photoelectric conversion unit 2 and the generated power of the fuel cell unit 22 are output to the first external circuit by turning SW7 and SW8 to the ON state. can do.
Further, when SW1, SW2, SW5, and SW6 are in the OFF state and SW3 and SW4 are in the ON state, the electromotive force generated when the photoelectric conversion unit 2 receives light is used as the first electrolysis electrode 8 and the second electrolysis electrode. 7 can be output.
For example, when SW3 and SW4 are in an OFF state and SW5 and SW6 are in an ON state, an electromotive force input from the second external circuit is output to the first electrolysis electrode 8 and the second electrolysis electrode 7. be able to. When SW1 and SW2 are in the OFF state and SW3, SW4, SW5, and SW6 are in the ON state, both the electromotive force generated by the photoelectric conversion unit 2 receiving light and the electromotive force input from the second external circuit Can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.

Further, when the power generation system includes a plurality of photoelectric conversion units 2, for example, when both the hydrogen production device 23 and the solar battery panel are provided and the power generation system includes an electric circuit as illustrated in FIG. , SW2, SW11, and SW12 are in the ON state and SW3, SW4, SW9, and SW10 are in the OFF state, the photovoltaic power of the plurality of photoelectric conversion units 2 can be output to the first external circuit. 4 is a circuit diagram in the case where the power generation system includes two photoelectric conversion units 2, the power generation system may include three or more photoelectric conversion units 2. For example, the power generation system includes a hydrogen production device 32 and a plurality of solar battery panels.
Further, when SW3, SW4, SW9, and SW10 are in the ON state and SW1, SW2, SW11, and SW12 are in the OFF state, the photovoltaic power of the plurality of photoelectric conversion units 2 can be output to the water electrolysis unit 21. .
Further, when SW3, SW4, SW11, SW12 are in the ON state and SW1, SW2, SW9, SW10 are in the OFF state, the photovoltaic power of one photoelectric conversion unit 2 can be output to the first external circuit, The photovoltaic power of the other photoelectric conversion unit 2 can be output to the water electrolysis unit 21.

For example, when the hydrogen production apparatus 23 has a cross section as shown in FIG. 8 and the power generation system has an electric circuit as shown in FIG. 16, for example, SW1 and SW2 are in an ON state, and SW3 and SW4 are in an OFF state. In this case, the electromotive force generated when the photoelectric conversion unit 2 receives light can be output to the first external circuit. In this case, when power is generated by the fuel cell unit 22, both the photovoltaic power of the photoelectric conversion unit 2 and the generated power of the fuel cell unit 22 are output to the first external circuit by turning SW7 and SW8 to the ON state. can do. Further, when SW1, SW2, SW3, and SW5 are in the OFF state and SW4 is in the ON state, the electromotive force generated by the photoelectric conversion unit 2 receiving light is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output.
For example, when SW1, SW2, and SW4 are in an OFF state and SW3 and SW5 are in an ON state, an electromotive force input from the second external circuit is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output. When SW1 and SW2 are in the OFF state and SW3, SW4 and SW5 are in the ON state, both the electromotive force generated when the photoelectric conversion unit 2 receives light and the electromotive force input from the second external circuit are It can output to the electrode 8 for 1 electrolysis and the electrode 7 for 2nd electrolysis.

For example, when the hydrogen production apparatus 23 has a cross section as shown in FIG. 9 and the power generation system has an electric circuit as shown in FIG. In this case, the electromotive force generated when the photoelectric conversion unit 2 receives light can be output to the first external circuit. In this case, when power is generated by the fuel cell unit 22, both the photovoltaic power of the photoelectric conversion unit 2 and the generated power of the fuel cell unit 22 are output to the first external circuit by turning SW7 and SW8 to the ON state. can do. Further, when SW1, SW2, SW3, and SW5 are in the OFF state and SW4 is in the ON state, the electromotive force generated by the photoelectric conversion unit 2 receiving light is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output.
For example, when SW1, SW2, and SW4 are in an OFF state and SW3 and SW5 are in an ON state, an electromotive force input from the second external circuit is applied to the first electrolysis electrode 8 and the second electrolysis electrode 7. Can be output. When SW1 and SW2 are in the OFF state and SW3, SW4 and SW5 are in the ON state, both the electromotive force generated when the photoelectric conversion unit 2 receives light and the electromotive force input from the second external circuit are It can output to the electrode 8 for 1 electrolysis and the electrode 7 for 2nd electrolysis.

For example, when the hydrogen production apparatus 23 has a cross section as shown in FIGS. 6 and 11 and the power generation system has an electric circuit as shown in FIG. 18, for example, SW1 and SW2 are in an ON state, and SW3 and SW4 are When the electromotive force generated when the photoelectric conversion unit receives light does not reach the electrolytic voltage of the electrolytic solution in the OFF state, the electromotive force generated when the photoelectric conversion unit 2 receives light is output to the first external circuit. can do. In this case, when power is generated by the fuel cell unit 22, both the photovoltaic power of the photoelectric conversion unit 2 and the generated power of the fuel cell unit 22 are output to the first external circuit by turning SW7 and SW8 to the ON state. can do.
Further, when SW1, SW2, SW3, and SW4 are in the OFF state, and the electromotive force generated by the photoelectric conversion unit 2 receiving light reaches the electrolytic voltage of the electrolytic solution, the photoelectric conversion unit 2 receives the light. The generated electromotive force can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7. Therefore, even when the electric circuit as shown in FIG. 18 is provided, the switching unit 29 causes the photoelectric conversion unit 2 to receive the electromotive force generated by the photoelectric conversion unit 2 receiving light and the photoelectric conversion unit 2 to receive light. It is possible to switch between the circuit that outputs the electromotive force generated by the above to the first electrolysis electrode 8 and the second electrolysis electrode 7.
When SW3 and SW4 are in the ON state and SW1 and SW2 are in the OFF state, the electromotive force input from the second external circuit or the electromotive force input from the second external circuit and the photoelectric conversion unit 2 receive light. Both the electromotive forces generated by this can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.

The switching unit 29 can input information from the control unit 12, and can switch circuits based on the input information. Thereby, the switching unit 29 can switch to the circuit selected by the control unit 12.
The switching unit 29 can also switch circuits based on the magnitude of the electromotive force generated when the photoelectric conversion unit 2 receives light. As a result, when the electric power output to the first external circuit is generated in the photoelectric conversion unit 2, the electromotive force generated in the photoelectric conversion unit 2 can be output to the first external circuit and output to the first external circuit. When the power to be generated is not generated in the photoelectric conversion unit 2, the electromotive force generated in the photoelectric conversion unit 2 can be output to the first electrolysis electrode 8 and the second electrolysis electrode 7.
Furthermore, the switching unit 29 can also switch circuits based on the magnitude of the electromotive force of the second external circuit. Thereby, when the electric power supplied from the second external circuit is larger than the electric demand, the first gas and the second gas can be produced using the electric power supplied from the second external circuit.

6). Humidity adjustment unit The humidity adjustment unit 10 is a part that adjusts the humidity of hydrogen gas or air (oxygen gas) supplied to the fuel cell unit 22. Further, the humidity control unit 10 may be a part that dehumidifies the hydrogen gas generated by the water electrolysis unit 21 and stored in the hydrogen storage unit 12.
The humidity control unit 10 can include a humidification unit 48 or a dehumidification unit 49. In addition, the humidity control unit 10 can include both the humidification unit 48 and the dehumidification unit 49. Moreover, you may consist of the humidification part 48 and the dehumidification part 49 which were provided apart. Moreover, the humidity control part 10 may be provided in the path | route of a hydrogen flow path, and the path | route of an air (oxygen gas) flow path, respectively.
The humidity control unit 10 can be provided so as to adjust the humidity of the hydrogen gas serving as the fuel of the fuel cell unit 22 and the humidity of the hydrogen gas stored in the hydrogen storage unit 12. Accordingly, the humidified hydrogen gas can be supplied to the fuel electrode 51 of the fuel cell unit 22, and the hydrogen gas generated by the water electrolysis unit 21 can be dehumidified and stored in the hydrogen storage unit 12. .
The humidity control unit 10 may be provided to adjust the humidity of the air or oxygen gas supplied to the air electrode 52 of the fuel cell unit 22 so as to dehumidify the oxygen gas generated by the water electrolysis unit 21. May be provided.

Examples of the humidifying unit 48 include a bubbler humidifying method in which a gas is bubbled into heated water and a water vapor adding method in which water vapor is directly supplied to the gas.
Note that “the humidity control unit 10 is in a humidified state” means that the humidity control unit 10 can immediately humidify the hydrogen gas or air (oxygen gas) supplied to the fuel cell unit 22. . For example, when the humidity control part 10 is a bubbler humidification system, it means that the temperature of water for bubbling hydrogen gas or air is raised. The hydrogen gas or air that is humidified by bubbling hydrogen gas or air into the heated water can be supplied to the fuel cell unit 22. Further, for example, when the humidity control unit 48 is a water vapor addition method, it means that the humidity control unit 48 can immediately add water vapor to the hydrogen channel or the air channel. In addition, the humidification part 48 may be another method. By making the humidity control unit 10 in a humidifiable state, the humidity control unit 10 can be put into the fuel cell power generation preparation mode.

Moreover, as the dehumidifying part 49, for example, a cooling type that dehumidifies by cooling the gas below the dew point temperature, a compression type that dehumidifies by compressing gas with a compressor, or a solid that easily adsorbs moisture It may be of an adsorption type that allows gas to pass through.
The humidity control unit 10 may include a humidity sensor that detects the humidity of the gas supplied to the fuel cell unit 22 or the humidity of the hydrogen gas stored in the hydrogen storage unit 12. Thereby, the humidity control part 10 can be controlled based on the measured value of a humidity sensor. The humidity sensor may be included in the sensor unit 41.
The humidity control unit 10 may be connected to the control unit 17 through a signal line as shown in FIG. 1 or may be controlled by a signal from the control unit 17. Moreover, the humidity control part 10 and the control part 17 may be provided so that signal transmission / reception can be performed wirelessly. Further, the humidity control unit 10 can “be in a humidified state” by a signal from the control unit 17.

7). Hydrogen Storage Unit The hydrogen storage unit 12 is provided so that the hydrogen gas generated by the water electrolysis unit 21 can be stored, and the stored hydrogen gas can be supplied to the fuel cell unit 22. Further, the hydrogen storage unit 12 can be electrically connected to the water electrolysis unit 21 or the fuel cell unit 22 through the hydrogen flow path.
The hydrogen storage unit 12 is, for example, a compressed hydrogen tank or a hydrogen storage alloy. When the hydrogen storage unit 12 is a compressed hydrogen tank, the hydrogen storage unit 12 may include a compressor for compressing the hydrogen gas generated by the water electrolysis unit 21. In addition, when the dehumidification part 49 is a compression system, the hydrogen gas compressed by the dehumidification part 49 can be stored in a compression hydrogen tank, and the hydrogen storage part 12 does not need to be equipped with a compressor.

8). Hydrogen channel, air (oxygen gas) channel In the hydrogen channel, the hydrogen gas generated by the water electrolysis unit 21 flows through the dehumidification unit 49 and is stored in the hydrogen storage unit 12, and the fuel in the fuel cell unit 22 A hydrogen gas that flows through the humidifying section 48 and is supplied to the fuel electrode 51 of the fuel cell section 22 may be provided. Moreover, the hydrogen flow path may have a plurality of valves provided so that the path through which hydrogen gas flows can be changed. Thus, the hydrogen flow path can be changed in accordance with the operation status of the water electrolysis unit 21 and the operation status of the fuel cell unit 22. Note that these valves may be connected to the control unit 17 by signal lines, or may be controlled by signals from the control unit 17. Further, these valves and the control unit 17 may be provided so that signals can be transmitted and received wirelessly. The valve may be provided so that the flow rate of the gas flowing through the hydrogen channel or the air channel can be adjusted. Further, the hydrogen flow path or the air flow path may be provided with a flow rate adjusting valve or a flow meter.

Further, the hydrogen flow path may have a path through which the hydrogen gas that has flowed through the fuel flow path 60 included in the fuel cell unit 22 is supplied to the fuel cell unit 22 again. You may have a path | route which is supplied to the battery part 22. FIG. These paths can also be changed by a valve, and may be controlled by the control unit 17. Note that the water contained in the hydrogen gas may be removed from the hydrogen gas flowing through the fuel flow path 60 by the condenser 45.
The hydrogen channel can be provided, for example, as shown in FIG.

In the air flow path, the oxygen gas generated by the water electrolysis unit 21 flows through the dehumidifying unit 49 and is stored in the air compressor 44, and the air or oxygen gas of the air compressor 44 flows through the humidifying unit 48 and the fuel cell. And a path supplied to the air electrode 52 of the unit 22. Moreover, the air flow path may have a plurality of valves provided so that a path through which air (oxygen gas) flows can be changed. As a result, the air flow path can be changed in accordance with the operation status of the water electrolysis unit 21 and the operation status of the fuel cell unit 22. Note that these valves may be connected to the control unit 17 by signal lines, or may be controlled by signals from the control unit 17. Further, these valves and the control unit 17 may be provided so that signals can be transmitted and received wirelessly. The air flow path may be provided so that air (oxygen gas) flowing through the air flow path 61 included in the fuel cell unit 22 is discharged to the outside. Further, the water contained in the air (oxygen gas) may be removed by the condenser 45 before the air (oxygen gas) is discharged.
For example, the air flow path can be provided as shown in FIG.

9. Water Channel The water channel can be provided so that the humidity control unit 10 (humidification unit 48, dehumidification unit 49), the water electrolysis unit 21, the condenser 45, and the water tank 46 are electrically connected. The water flow path can have a pump or a valve for circulating water.
The water channel can be provided as shown in FIG. 2, for example. If it demonstrates using FIG. 2, the reduction | decrease of the electrolyte solution in the water electrolysis part 21 can be prevented by supplying the water stored in the water tank 46 to the water electrolysis part 21 with the pump 1 (P1). Further, the water separated by the condenser 45 can be collected in the water tank 46 by opening the valves 9 and 10 (V9 and V10). The water generated by the dehumidifying unit 49 can be used by the humidifying unit 48, and the water in the water tank 46 can be supplied to the humidifying unit 48 at P2 and P3.
In addition, these valves and pumps may be connected to the control unit 17 through signal lines, or may be controlled by signals from the control unit 17. Moreover, these valves, pumps, and controller 17 may be provided so that signals can be transmitted and received wirelessly.

10. Sensor Unit The sensor unit 41 can include a solar radiation meter or an illuminance sensor. Thereby, information regarding the amount of light incident on the photoelectric conversion unit 2 can be obtained. Further, the output of the solar radiation meter or the illuminance sensor included in the sensor unit 41 may be “information relating to the photovoltaic power of the photoelectric conversion unit 2”.
The sensor unit 41 may include a humidity sensor that detects the humidity of hydrogen gas or air (oxygen gas) supplied to the fuel cell unit 22.
The sensor unit 41 can output a detection signal to the control unit 17. Thereby, the power generation system of the present embodiment can be controlled by the control unit 17 based on the detection signal of the sensor unit 41.

11. Control Unit The control unit 17 has a function of controlling the power generation system based on information on the photovoltaic power of the photoelectric conversion unit 2 or information on demand power. Further, the control unit 17 can be connected to the switching unit 29, the fuel cell unit 22, the humidity control unit 10, the sensor unit 41, the valve, and the pump by a signal line or wirelessly. The control unit 17 can be connected to an external information communication network. As a result, the power generation system of the present embodiment can be controlled by the control unit 17.

  The control unit 17 can have input means, setting means, and output means. In addition, the control unit 17 has a sensor unit 14, an external information network, a server, a humidity control unit 10, and a fuel cell unit through a wired or wireless signal line for input by an input unit or output by an output unit. 22, a switching unit 29, a valve, a pump, the photoelectric conversion unit 2, and the like.

The input unit can input, for example, a signal from the sensor unit 41 or a signal of a measured value of the photovoltaic power of the photoelectric conversion unit 2. Thus, the control unit 17 can input “information on the photovoltaic power of the photoelectric conversion unit 2”.
The input means can input information from the electric power company, Web information, and solution server information. Thus, the control unit 17 can input “information on demand power”.
Based on the information input to the input means, the setting means turns on / off the switch included in the switching unit 29, starts / stops / adjusts the output of the fuel cell unit 22, starts / stops the humidity control unit 10, Open / close, pump start / stop, etc. can be set.
The output unit can output the information set by the setting unit to the humidity control unit 10, the fuel cell unit 22, the switching unit 29, a valve, a pump, and the like. The humidity control unit 10, the fuel cell unit 22, the switching unit 29, the valve, the pump, and the like can be controlled by information output from the output unit.
The power generation system of this embodiment can be controlled by these means.

FIG. 19 is a flowchart for controlling the power generation system by the control unit. By controlling as in this flowchart, the power generation system can be switched between the fuel cell power generation mode, the hydrogen generation mode, the solar cell + fuel cell power generation mode, the solar cell power generation mode, and the solar cell power generation + hydrogen generation mode.
Here, each mode of the power generation system will be described with reference to FIGS. Here, a power generation system including the above-described hydrogen production apparatus 23 and the fuel cell unit 22 will be described. Moreover, the power generation system provided with the solar cell panel in addition to the hydrogen production apparatus 23 will also be described. In this case, the photoelectric conversion unit 2 is included in the hydrogen production apparatus 23 and included in the solar cell panel, and becomes a plurality.

First, the control part 17 can input the photovoltaic power (information regarding the photovoltaic power of the photoelectric conversion part 2) and demand power (information regarding demand power) of the photoelectric conversion part 2 by an input means. The photovoltaic power of the photoelectric conversion unit 2 may be the photovoltaic power of the photoelectric conversion unit 2 measured from the wiring of the photoelectric conversion unit 2 or the wiring of the switching unit 29. The photovoltaic power of the photoelectric conversion unit 2 predicted from the above may be used. In the latter case, the amount of solar radiation and illuminance are input to the input unit, and the control unit 17 can also calculate the photovoltaic power.
The power demand can be input from an external information network or server by an input means. This is the power necessary to supply the consumed power, and the amount of power predicted by the server or the like can be input.

Next, the control unit 17 determines whether one of the photovoltaic power and the demand power of the photoelectric conversion unit 2 exceeds a predetermined value. Here, in the case of the photovoltaic power of the photoelectric conversion unit 2, the predetermined value is a predetermined power amount sufficient to output the photovoltaic power to an external circuit or to the water electrolysis unit 21. The predetermined value of the demand power is a predetermined demand power amount that does not require the supply of power from the photoelectric conversion unit 2 or the fuel cell unit 22. For example, it is the amount of power demand that can be satisfied only with power from the power system.
When the control unit 17 determines that both the photovoltaic power and the demand power of the photoelectric conversion unit 2 are lower than the predetermined values, the control unit 17 sends a signal for setting the power generation system to the standby mode from the output unit. Output to the component. For example, it is nighttime and there is almost no power demand of the facility where the power generation system supplies power.
In such a case, for example, the control unit 17 can output a signal for turning off all the switches to the switching unit 29, and for the valve, a closing signal, a pump, a fuel cell unit 22, and a control unit. A signal for turning OFF can be output to the wet portion 10. As a result, the power generation system can be set to the standby mode.

When the control unit 17 determines that one of the photovoltaic power and the demand power of the photoelectric conversion unit 2 exceeds a predetermined value, the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 exceeds the predetermined value. Judge whether or not.
When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 is lower than the predetermined value and the demand power is higher than the predetermined value, the control unit 17 outputs a signal for setting the power generation system to the fuel cell power generation mode from the output unit. Output to each component. For example, it is nighttime and it is necessary to supply power by the power generation system.
In such a case, for example, the control unit 17 outputs a signal for starting the fuel cell unit 22 to the fuel cell unit 22 and outputs a signal for turning on the humidifying unit 48, and V1 (valve 1). Alternatively, a signal for opening V2, V3, V4, V5, and V6 is output to each valve. Further, the control unit 17 outputs a signal for turning on SW7 (switch 7) and SW8 to the switching unit 29. Thereby, the electric power generated by the fuel cell unit 22 can be supplied to the first external circuit, and the fuel cell power generation mode can be set.
Thereafter, the control unit 17 can output a fuel cell power generation control signal to the fuel cell unit 22 or the like. Specifically, the control unit 17 inputs demand power from the input means, changes the generated power of the fuel cell unit 22 based on the input demand power, and sends a signal for performing a power load following operation to the fuel cell. It can output to the part 22, the humidity control part 10, a valve | bulb, etc.

When the control unit 17 determines that the photovoltaic power in the photoelectric conversion unit 2 exceeds the predetermined value, the control unit 17 determines whether the demand power exceeds the predetermined value.
When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 exceeds the predetermined value and the demand power is lower than the predetermined value, the control unit 17 outputs a signal for setting the power generation system to the hydrogen generation mode from the output unit. Output to the component. For example, this is the case when there is little demand for power at a facility where the power generation system supplies power during the day.
In such a case, the control unit 17 outputs a signal for turning off SW1 and SW2 and turning on SW3 and SW4 to the switching unit 29. Thereby, the photovoltaic power of the photoelectric conversion unit 2 can be output to the water electrolysis unit 21, and hydrogen gas can be produced by the water electrolysis unit 21. Further, when the power generation system includes a solar battery panel, specifically, when the power generation system has an electric circuit diagram as shown in FIG. 4, the control unit 17 switches SW1, SW2, SW11, and SW12 to the switching unit 29. A signal that turns off and turns on SW3, SW4, SW9, and SW10 is output. Thus, hydrogen gas can be produced by the water electrolysis unit 21 using both the photovoltaic power of the photoelectric conversion unit 2 included in the hydrogen production device 23 and the photovoltaic power of the solar cell panel.
In addition, the control unit 17 outputs a signal for turning on the dehumidifying unit 49, the air compressor 44, and the hydrogen storage unit 12, and outputs a signal for opening the valve to V2 (valve 2), V3, V7, and V8. Can be output. Accordingly, the hydrogen gas and oxygen gas generated in the water electrolysis unit 21 can be dehumidified by the dehumidification unit 49 and then stored in the hydrogen storage unit 12 and the air compressor 44, respectively. The stored hydrogen gas and oxygen gas can be supplied to the fuel cell unit 22 when the fuel cell unit 22 is operated.

When the control unit 17 determines that both the photovoltaic power and the demand power of the photoelectric conversion unit 2 exceed a predetermined value, the control unit 17 determines whether the photovoltaic power of the photoelectric conversion unit 2 exceeds the demand power. Judge whether or not.
When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 is lower than the demand power, the control unit 17 outputs a signal for setting the power generation system to the solar cell + fuel cell power generation mode from the output unit. Output to. For example, this is the case when there is a large amount of power demand in a facility where the power generation system supplies power during the daytime.
In such a case, for example, the control unit 17 outputs a signal for starting the fuel cell unit 22 to the fuel cell unit 22 and outputs a signal for turning on the humidifying unit 48, and V1 (valve 1). Alternatively, a signal for opening V2, V3, V4, V5, and V6 is output to each valve. Further, the control unit 17 outputs a signal for turning on SW1, SW2, SW7, and SW8 and turning off SW3 and SW4 to the switching unit 29. Thereby, both the electric power generated by the fuel cell unit 22 and the photovoltaic power of the photoelectric conversion unit 2 can be supplied to the first external circuit, and the solar cell + fuel cell power generation mode can be set.
Thereafter, the control unit 17 can output a fuel cell power generation control signal to the fuel cell unit 22 or the like. Specifically, the control unit 17 inputs the demand power and the photovoltaic power of the photoelectric conversion unit 2 by input means, and varies the generated power of the fuel cell unit 22 based on the inputted demand power and photovoltaic power. Then, a signal for performing the power load following operation can be output to the fuel cell unit 22, the humidity control unit 10, the valve, and the like.

When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 exceeds the demand power, the control unit 17 determines whether the photovoltaic power of the photoelectric conversion unit 2 greatly exceeds the demand power. To do.
When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 does not greatly exceed the demand power, the control unit 17 outputs, from the output means, a signal for setting the power generation system to the solar cell power generation mode to each component. To do. For example, it is in the daytime, the demand power can be satisfied with the photovoltaic power of the photoelectric conversion unit 2, and there is not much surplus power.
In such a case, for example, the control unit 17 outputs a signal for turning on SW1 and SW2 and turning off SW3, SW4, SW7, and SW8 to the switching unit 29. Thereby, the photovoltaic power of the photoelectric conversion unit 2 can be supplied to the first external circuit, and the solar cell power generation mode can be set.

When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 greatly exceeds the demand power, the control unit 17 outputs a signal for setting the power generation system to the solar cell power generation + hydrogen generation mode from the output unit. Output to the element. For example, there is daytime, demand power can be satisfied with the photovoltaic power of the photoelectric conversion unit 2, and there is surplus power.
For example, when the power generation system includes a plurality of photoelectric conversion units 2 as illustrated in FIG. 4, the photovoltaic power of some of the photoelectric conversion units 2 is output to the water electrolysis unit 21 and the photovoltaic power of other photoelectric conversion units 2 is output. Can be output to the first external circuit. When the switching unit 29 has an electric circuit as shown in FIG. 4, the control unit 17 sends a signal that turns on SW3, SW4, SW11, and SW12 and turns off SW1, SW2, SW9, and SW10 to the switching unit 29. Can be output. Thereby, the photovoltaic power of the photoelectric conversion unit 2 can be output to both the water electrolysis unit 21 and the first external circuit, and the solar cell power generation + hydrogen generation mode can be obtained.

The power generation system can be switched to each mode according to the flowchart as shown in FIG. 19. For example, when switching from the solar cell power generation mode to the solar cell + fuel cell power generation mode, the fuel cell unit 22 is activated to supply constant power. It takes a certain amount of time to do so, and there is a possibility that power shortage may occur temporarily. In order to suppress the occurrence of this power shortage, it is conceivable to increase the demand power to some extent. In this case, however, the fuel cell unit 22 may be started earlier and energy loss may occur.
As a method for suppressing such power shortage and reducing energy loss as much as possible, the fuel cell unit 22 and the humidity control unit 10 are set in the fuel cell power generation preparation mode before the power generation by the fuel cell unit 22 is started. It can be considered.

FIG. 20 is a flowchart when the controller 17 switches the power generation system from the solar cell power generation mode to the solar cell + fuel cell power generation mode. The fuel cell power generation preparation mode will be described with reference to FIG. Here, the switching from the solar cell power generation mode to the solar cell + fuel cell power generation mode will be described. Based on this, the fuel cell unit 22 and the humidity control unit 10 can be set to the fuel cell power generation preparation mode.
When the photovoltaic power of the photoelectric conversion unit 2 exceeds the demand power and there is not much surplus power, the power generation system is controlled in the solar cell power generation mode. In this case, if the photovoltaic power decreases due to the decrease in the amount of light incident on the photoelectric conversion unit 2 or the demand power increases, it is necessary to switch the power generation system to the solar cell + fuel cell power generation mode.
For this switching, first, the control unit 17 can input the photovoltaic power and demand power of the photoelectric conversion unit 2 by the input means. Next, the control unit 17 determines whether or not the difference obtained by subtracting the demand power from the photovoltaic power is less than a predetermined value. This predetermined value can be set to a value for preventing power shortage.

When the control unit 17 determines that the difference obtained by subtracting the demand power from the photovoltaic power is less than a predetermined value, the control unit 17 sets the fuel cell unit 22 and the humidity control unit 10 from the output unit to the fuel cell power generation preparation mode. Is output to each component. For example, the control unit 17 outputs a signal for raising the temperature to a predetermined temperature equal to or lower than the operating temperature, and outputs a signal for turning on the humidifying unit 48 in the hydrogen flow channel and the air flow channel to the fuel cell unit 22. be able to. As a result, the fuel cell unit 22 can be immediately brought to the operating temperature, and the fuel cell power generation preparation mode in which the humidified hydrogen gas and the humidified air can be immediately supplied to the fuel cell unit 22 is set. be able to.
Thereafter, the control unit 17 determines whether or not the photovoltaic power of the photoelectric conversion unit 2 is lower than the demand power. When the control unit 17 determines that the photovoltaic power of the photoelectric conversion unit 2 is lower than the demand power, the control unit 17 outputs a signal for setting the power generation system to the solar cell + fuel cell power generation mode from the output unit. Output to.
At this time, since the fuel cell unit 22 and the humidity control unit 10 are set in the fuel cell power generation preparation mode in advance, the fuel cell unit 22 can output the generated power to the first external circuit quickly, and power shortage occurs. Can be suppressed. In addition, by setting the fuel cell unit 22 in the fuel cell power generation preparation mode in advance, it is not necessary to start the fuel cell unit 22 early, and energy loss can be suppressed.

    1: Translucent substrate 2: Photoelectric conversion part 4: First electrode 5: Second electrode 7: Electrode for second electrolysis 8: Electrode for first electrolysis 9: First electroconductive part 10: Humidity control part 11: Insulation part 12: Hydrogen storage unit 13: Partition 14: Second substrate 15: Electrolyte chamber 16: Sealing material 17: Control unit 18: Water supply port 19: Second gas discharge port 20: First gas discharge port 21: Water electrolysis unit 22 : Fuel cell unit 23: Hydrogen production device 24: Second conductive unit 25: Third conductive unit 28: Photoelectric conversion layer 29: Switching unit 30: Translucent electrode 31: Back electrode 33: Fourth conductive unit 35: Semiconductor unit 36: p-type semiconductor part 37: n-type semiconductor part 40: isolation 41: sensor part 42: hydrogen cylinder 44: air compressor 45: condenser 46: water tank 48: humidification part 49: Dehumidification part 50: Wiring 51: Fuel electrode 52: Air electrode 53: Electrolyte membrane 55: Current collector plate 57: Separator 58: Connection plate 60: Fuel flow path 61: Air flow path

Claims (35)

A water electrolysis unit that electrolyzes water to generate hydrogen gas and oxygen gas; a photoelectric conversion unit that outputs photovoltaic power generated by receiving sunlight to an external output or the water electrolysis unit; A fuel cell unit that generates hydrogen gas as fuel and outputs the electromotive force externally according to the photovoltaic power of the conversion unit, stores the hydrogen gas generated by the water electrolysis unit, and stores the stored hydrogen gas in the fuel cell A hydrogen storage unit supplied to the fuel cell unit, a humidity control unit that adjusts the humidity of the hydrogen gas or air supplied to the fuel cell unit, and a control unit,
The said control part is provided with the function which controls the said humidity control part based on the information regarding the photovoltaic power of the said photoelectric conversion part, or the information regarding demand power, The power generation system characterized by the above-mentioned.   The control unit is in a state where the humidity control unit can be humidified before starting supply of hydrogen gas or air to the fuel cell unit based on information on photovoltaic power and information on demand power of the photoelectric conversion unit. The power generation system according to claim 1, further comprising a function of controlling the humidity control unit.   Based on the information about the photovoltaic power of the photoelectric conversion unit and the information about demand power, the control unit is configured to determine whether the fuel cell unit has a predetermined operating temperature or less before starting to supply hydrogen gas or air to the fuel cell unit. The power generation system according to claim 1, further comprising a function of controlling the fuel cell unit so as to raise the temperature.   The said humidity control part is a power generation system as described in any one of Claims 1-3 which adjusts the humidity of the hydrogen gas stored in the said hydrogen storage part.   The power generation system according to any one of claims 1 to 4, wherein the humidity adjusting unit includes a humidifying unit and a dehumidifying unit. A hydrogen flow path;
In the hydrogen flow path, hydrogen gas generated by the water electrolysis unit flows through the dehumidification unit, a path where the hydrogen gas is stored in the hydrogen storage unit, and hydrogen gas serving as fuel for the fuel cell unit flows through the humidification unit. The power generation system according to claim 5, further comprising a path supplied to the fuel cell unit.   The power generation system according to claim 6, wherein the hydrogen flow path has a plurality of valves provided so that a path through which hydrogen gas flows can be changed.   The switching unit for switching between a circuit for outputting the photovoltaic power of the photoelectric conversion unit to the water electrolysis unit and a circuit for outputting the photovoltaic power of the photoelectric conversion unit to the outside. The power generation system described in 1.   The power generation system according to claim 8, wherein the switching unit is provided so that either one or both of the photovoltaic power of the photoelectric conversion unit and the generated power of the fuel cell unit can be externally switched by switching a circuit.   The control unit includes: an input unit that inputs information; a setting unit that sets a control mode of the power generation system based on information input from the input unit; and a configuration of the power generation system that includes information set by the setting unit. The power generation system according to any one of claims 1 to 9, further comprising output means for outputting to the element. A sensor unit including a solar radiation meter or an illuminance sensor;
The power generation system according to claim 10, wherein the input unit inputs information from the sensor unit.   The power generation system according to claim 10 or 11, wherein the input means inputs information from an electric power company, Web information, and solution server information. The photoelectric conversion unit has a light receiving surface and a back surface thereof,
The water electrolysis unit is provided on the back side of the photoelectric conversion unit,
The said photoelectric conversion part and the said water electrolysis part are the electric power generation systems as described in any one of Claims 1-12 which comprise a hydrogen production apparatus. The hydrogen production apparatus includes a first electrolysis electrode and a second electrolysis electrode provided on the back surface of the photoelectric conversion unit, respectively.
When sunlight is incident on the light receiving surface of the photoelectric conversion unit and the first and second electrolysis electrodes are in contact with the electrolytic solution,
The first and second electrolysis electrodes are provided so that the electrolysis solution can be electrolyzed using the electromotive force generated by the photoelectric conversion unit receiving light to generate the first gas and the second gas, respectively. ,
The power generation system according to claim 13, wherein one of the first gas and the second gas is hydrogen gas and the other is oxygen gas. The photoelectric conversion unit generates an electromotive force between the light receiving surface and the back surface by receiving light,
The first electrolysis electrode is provided so as to be electrically connected to the back surface of the photoelectric conversion unit,
The power generation system according to claim 14, wherein the second electrolysis electrode is provided so as to be electrically connected to a light receiving surface of the photoelectric conversion unit.   The power generation system according to claim 15, wherein the hydrogen production apparatus further includes an insulating part provided between the second electrolysis electrode and the back surface of the photoelectric conversion part.   The power generation system according to claim 16, wherein the hydrogen production apparatus further includes a first electrode that contacts a light receiving surface of the photoelectric conversion unit.   The power generation system according to claim 17, wherein the hydrogen production apparatus further includes a first conductive portion that electrically connects the first electrode and the second electrolysis electrode.   The power generation system according to claim 18, wherein the first conductive portion is provided in a contact hole that penetrates the photoelectric conversion portion. The insulating part is provided so as to cover a side surface of the photoelectric conversion part,
The power generation system according to claim 18, wherein the first conductive portion is provided on a portion that is a part of the insulating portion and covers a side surface of the photoelectric conversion portion. The insulating part is provided so as to cover a side surface of the photoelectric conversion part,
The power generation system according to claim 17, wherein the second electrolysis electrode is provided on a portion that is a part of the insulating portion and covers a side surface of the photoelectric conversion portion, and is in contact with the first electrode.   The power generation system according to any one of claims 15 to 21, wherein the photoelectric conversion unit includes a photoelectric conversion layer including a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer. The photoelectric conversion unit generates a potential difference between the first and second areas on the back surface of the photoelectric conversion unit by receiving light,
The power generation system according to claim 14, wherein the first area is provided to be electrically connected to the first electrolysis electrode, and the second area is provided to be electrically connected to the second electrolysis electrode. .   The said hydrogen production apparatus is further provided with the insulation part which is provided between the 1st and 2nd electrode for electrolysis, and the back surface of the said photoelectric conversion part, and has an opening on a 1st area and a 2nd area. 24. The power generation system according to 23. The photoelectric conversion part is made of at least one semiconductor material having an n-type semiconductor part and a p-type semiconductor part,
The power generation system according to claim 23 or 24, wherein one of the first and second areas is a part of the n-type semiconductor part, and the other is a part of the p-type semiconductor part. The hydrogen production apparatus further includes a translucent substrate,
The said photoelectric conversion part is a power generation system as described in any one of Claims 14-25 provided on the said translucent board | substrate. The photoelectric conversion unit includes a plurality of photoelectric conversion layers connected in series,
The power generation system according to any one of claims 14 to 26, wherein the plurality of photoelectric conversion layers are provided so as to supply an electromotive force generated by receiving light to the first electrolysis electrode and the second electrolysis electrode. . Of the first electrolysis electrode and the second electrolysis electrode, one is a hydrogen generation unit that generates H ₂ from the electrolytic solution, and the other is an oxygen generation unit that generates O ₂ from the electrolytic solution,
The hydrogen generation part and the oxygen generation part each include a hydrogen generation catalyst that is a catalyst for a reaction in which H ₂ is generated from the electrolytic solution and an oxygen generation catalyst that is a catalyst for a reaction in which O ₂ is generated from the electrolytic solution. The power generation system according to any one of -27.   29. The power generation system according to claim 28, wherein at least one of the hydrogen generation unit and the oxygen generation unit has a catalyst surface area larger than an area of a light receiving surface of the photoelectric conversion unit.   30. The power generation system according to claim 28 or 29, wherein at least one of the hydrogen generation unit and the oxygen generation unit is a porous conductor carrying a catalyst.   The power generation system according to any one of claims 28 to 30, wherein the hydrogen generation catalyst includes at least one of Pt, Ir, Ru, Pd, Rh, Au, Fe, Ni, and Se.   32. The power generation system according to claim 28, wherein the oxygen generation catalyst includes at least one of Mn, Ca, Zn, Co, and Ir. The hydrogen production apparatus further includes a translucent substrate, an electrolytic solution chamber, and a back substrate provided on the first electrolysis electrode and the second electrolysis electrode,
The photoelectric conversion unit is provided on the translucent substrate,
The power generation system according to any one of claims 14 to 32, wherein the electrolyte chamber is provided between the first and second electrolysis electrodes and the back substrate.   The hydrogen production apparatus further includes a partition partitioning an electrolyte chamber between the first electrolysis electrode and the back substrate and an electrolyte chamber between the second electrolysis electrode and the back substrate. The power generation system described.   The power generation system according to claim 34, wherein the partition wall includes an ion exchanger.