JP7364182B2 - Hydrogen-based power supply system and hydrogen-based power supply method - Google Patents

Description

The present invention relates to a hydrogen-based power supply system and a hydrogen-based power supply method.

The Basic Energy Plan approved by the Cabinet in April 2014 stipulates that efforts will be accelerated to realize a "hydrogen society" in which hydrogen is used in daily life and industrial activities, and the national and Tokyo metropolitan governments have announced plans for 2020. There is a growing movement toward the active use of hydrogen at the Tokyo Olympics and the subsequent spread of a hydrogen society. The introduction of the Feed-in Tariff (FIT) system for renewable energy in July 2012 significantly changed the non-residential solar power generation market (public and industrial sectors). According to JPEA PV OUTLOOK 2030, the proportion of non-residential use in total domestic shipments was 50% in fiscal 2012 (compared to 3.8GW of total domestic shipments), 73% in fiscal 2013 (compared to 8.4GW), In the first half of FY2014, it has significantly increased by 77% (compared to the total domestic shipment of 4.3GW in the first half).

Due to the large amount of certified solar power generation facilities, there is a concern that if all of them are in operation, the amount of power supplied by solar power generation will exceed the amount of demand during light load periods when power demand is low, so designated electric utilities It was decided that grid connection would be made on the condition of ``unlimited and uncompensated output curtailment.'' In the future, as the amount of solar power generation connected to the grid increases, output curtailment aimed at adjusting power supply and demand will become a reality.

When output curtailment is implemented, that amount of renewable energy is discarded, so from the perspective of efficient energy use, energy that is discarded using storage batteries etc. (hereinafter referred to as surplus electricity) It is advisable to store it. Hydrogen has been attracting attention in recent years as a means of storing surplus electricity. Compared to storage using storage batteries, it has the disadvantage that there is a large drop in efficiency when converting electricity to hydrogen and from hydrogen to electricity, but it is suitable for large-capacity, long-term energy storage. Note that systems for producing, storing, and utilizing (power generation) hydrogen using electric power are described in, for example, Patent Document 1 and Patent Document 2.

International Publication No. 2017/013751 JP2003-061251A

The use of hydrogen storage alloys has also been proposed to store surplus hydrogen compactly and safely. However, since common hydrogen storage alloys burn when ignited, they fall under the category of hazardous materials under the Fire Service Act. Therefore, it is conceivable to use a titanium/iron-based hydrogen storage alloy as a hydrogen storage alloy that does not fall under the category of hazardous materials under the Fire Service Act. However, in titanium-iron hydrogen storage alloys, there are few regions where the pressure plateaus on the PCT (Pressure Composition Temperature) diagram, and the pressure hysteresis during absorption and release is large. Therefore, in order to absorb and release hydrogen while saving energy, it is necessary to manage a wide temperature range and use heat effectively.

In view of the above-mentioned problems, an object of the present invention is to provide a hydrogen-based power supply system and a hydrogen-based power supply method that can effectively control the temperature of each part of the system.

A hydrogen-based power supply system according to one aspect of the present invention is a hydrogen-based power supply system that supplies power generated using hydrogen as at least part of the power supplied to a load, and is a hydrogen-based power supply system that uses renewable energy. A hydrogen production device that produces hydrogen by electrolyzing water accumulated in an electrolytic cell using power obtained from a power source obtained from a power source or a commercial power source, and storing the hydrogen produced in an alloy tank filled with a hydrogen storage alloy. a hydrogen storage device, a fuel cell that generates electricity using the hydrogen stored in the hydrogen storage device, a cooling device, a heating device, a heat medium path that recovers exhaust heat from the electrolytic cell of the hydrogen production device; Determine whether the temperature or pressure of any of the electrolytic cell, the alloy tank, or the fuel cell exceeds a reference temperature or pressure, and if the temperature or pressure exceeds the reference temperature or pressure, adjust the reference temperature or pressure. the electrolytic cell, the alloy tank, and the fuel cell, the cooling device is configured to cool the electrolytic cell, the alloy tank, and the fuel cell, and the control device is configured to cool the electrolytic cell, the alloy tank, and the fuel cell by the cooling device; When the generated waste heat is recovered by the heat medium path and hydrogen is released from the alloy tank, the alloy tank is heated by circulating the heat medium path using the heating device.

A hydrogen-based power supply method according to one aspect of the present invention is a hydrogen-based power supply method that supplies power generated using hydrogen as at least a portion of the power supplied to a load, and which uses renewable energy. A step of electrolyzing water accumulated in an electrolytic cell using power obtained from a power source obtained by a power source or a power source from a commercial power source to produce hydrogen using a hydrogen production device , and transferring the produced hydrogen to an alloy tank in which a hydrogen storage alloy is sealed. a step of storing hydrogen; a step of generating electricity with a fuel cell using the stored hydrogen; and whether the temperature or pressure of any of the electrolyzer, the alloy tank, and the fuel cell exceeds a reference temperature or pressure. a step of cooling any one of the electrolytic cell, the alloy tank, and the fuel cell that exceeds the reference temperature or pressure with a cooling device if the temperature or pressure exceeds the reference temperature or pressure; When the exhaust heat generated from the electrolyzer is recovered by the heat medium path in response to the activation of the hydrogen production device and hydrogen is released from the alloy tank , by circulating the heat medium path using a heating device. and heating the alloy tank.

According to the present invention, the temperature of each part, such as the electrolytic cell, hydrogen storage alloy, and fuel cell, can be cooled by radiating heat using the cooling device. This allows effective temperature control of each part of the system.

1 is a block diagram showing an overview of the configuration of a hydrogen utilization system according to an embodiment of the present invention. FIG. 2 is a PCT diagram of an example of a titanium/iron-based hydrogen storage alloy. FIG. 3 is an explanatory diagram of the operation of the cooling device in the hydrogen utilization system according to the embodiment of the present invention. It is an explanatory view of operation of a heating device in a hydrogen utilization system concerning an embodiment of the present invention. It is a flowchart which shows operation plan planning processing in a hydrogen utilization system concerning an embodiment of the present invention. 1 is a flowchart showing an overview of operation control in the entire hydrogen utilization system according to an embodiment of the present invention. It is a flow chart explaining hydrogen production processing and hydrogen storage processing in a hydrogen utilization system concerning an embodiment of the present invention. It is a flow chart explaining hydrogen production stop processing. It is a flow chart explaining hydrogen release processing and hydrogen power generation processing in a hydrogen utilization system concerning an embodiment of the present invention. It is a flow chart explaining hydrogen power generation stop processing.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an overview of the configuration of a hydrogen utilization system 1 according to an embodiment of the present invention.

As shown in FIG. 1, the hydrogen utilization system 1 according to the embodiment of the present invention includes a renewable energy power source 11, a storage battery 12, a power load 13, a hydrogen production device 14, a hydrogen storage device 15, and a fuel cell. 16, a heating device 17, a cooling device 18, a heat load 19, and a control device 20.

The renewable energy power source 11 generates power using renewable energy such as solar power generation and wind power generation. The storage battery 12 charges and discharges power to compensate for the unstable fluctuation component of the amount of power generated by the renewable energy power source 11. The power load 13 is load equipment in a building that consumes and utilizes power, such as lighting equipment, air conditioning equipment, and various electric/electronic equipment.

The hydrogen production device 14 produces hydrogen from the renewable energy power source 11 and the commercial power source 31. As the hydrogen production device 14, one that produces hydrogen by, for example, solid polymer (PEM) type water electrolysis is used. Solid polymer type water electrolysis is characterized by being easy to electrolyze at high temperatures, having high electrolysis efficiency, and being easy to start and stop. The hydrogen production device 14 includes an electrolytic cell 21 and a regenerative dehumidifier 22. Pure water is accumulated in the electrolytic cell 21. In the electrolytic cell 21, hydrogen ions move through the solid polymer electrolyte membrane, water is electrolyzed, and hydrogen is generated. In this embodiment, electrolysis is performed at a pressure of 0.9 MPaG or less, which is exempt from high-pressure gas application, and the electrolytic current can be controlled according to the amount of renewable energy generated. Moisture contained in the generated hydrogen gas is removed by the regenerative dehumidifier 22. Furthermore, the regenerative dehumidifier 22 is designed to reduce hydrogen emissions during steady operation as much as possible by reusing the highly humid hydrogen gas generated during heating and regeneration of the dehumidifier. Moreover, the exhaust heat of the electrolytic cell 21 is collected in the heat medium path 50, circulated, and used as a heat source.

The hydrogen storage device 15 stores hydrogen using a hydrogen storage alloy. The hydrogen storage device 15 includes an alloy tank 23 filled with a hydrogen storage alloy. The hydrogen storage alloy may be any alloy that does not fall under the category of hazardous material under the Fire Service Act, such as a titanium/iron alloy, and alloys other than titanium/iron alloys may be used. Further, the alloy tank 23 is allowed to operate at a pressure of 0.9 MPaG or less, which is outside the scope of the High Pressure Gas Safety Act. The characteristics of hydrogen storage alloys are shown in PCT diagrams. FIG. 2 is a PCT diagram of an example of a titanium-iron hydrogen storage alloy. In FIG. 2, the horizontal axis shows the hydrogen composition (ratio of hydrogen atoms H to metal atoms M), and the vertical axis shows the equilibrium hydrogen pressure. As shown in FIG. 2, in titanium-iron hydrogen storage alloys, there are few areas where the pressure plateaus on the PCT diagram, and the pressure hysteresis during absorption and release is large. Cooling and heating of the alloy tank 23 is performed using a heat medium from a heat medium path 50. In this example, the alloy tank 23 is cooled to about 20 degrees Celsius during storage, heated to about 60 degrees Celsius during discharge, and the alloy composition is adjusted so that the temperature range is 20 to 60 degrees Celsius.

The fuel cell 16 generates electricity using hydrogen. As the fuel cell 16, for example, a polymer electrolyte fuel cell (PEFC) is used. Polymer electrolyte fuel cells are characterized by being easy to start and stop, making it easy to respond to fluctuating building power demands. Fuel cell 16 includes a stack 24 and a heat exchanger 25. In the stack 24, electric power is generated from the hydrogen sent from the hydrogen storage device 15. In addition, the heat obtained during power generation by the fuel cell 16 is recovered by the heat exchanger 25 into the heat medium path 50 and supplied to the heat load 19 in the building, and a part of it is supplied to the hydrogen storage device 15. The alloy tank 23 is heated. Thereby, hydrogen is released, and hydrogen necessary for power generation can be stably and continuously obtained from the alloy tank 23.

The heating device 17 is a heat source that heats each part of the device. Furthermore, when releasing hydrogen from the alloy tank 23 of the hydrogen storage device 15, the heating device 17 is used to heat the heating medium that circulates through the heating medium path 50 and is sent to the alloy tank 23. The cooling device 18 cools each part within the system. The heat load 19 is equipment in the building that consumes heat as a load, such as a water heater or an air conditioner.

A renewable energy power source 11 , a storage battery 12 , a power load 13 , a hydrogen production device 14 , and a fuel cell 16 are connected to a power line 30 from a commercial power source 31 . A measuring instrument M1 is provided at the entrance of the commercial power source 31. A measuring device M2 is provided at the entrance of the hydrogen production device 14. A measuring device M3 is provided at the entrance of the renewable energy power source 11. A measuring device M4 is provided at the entrance of the storage battery 12. A measuring device M5 is provided at the entrance of the power load 13. A measuring device M6 is provided at the outlet of the fuel cell 16. These measuring devices M1 to M6 are measuring devices that monitor current, voltage, power, integrated power, and the like. The measured values of these measuring instruments M1 to M6 are sent to the control device 20.

A hydrogen release valve 41 is provided in the hydrogen supply pipe between the hydrogen production device 14 and the hydrogen storage device 15. Further, a hydrogen release valve 42 is provided in the hydrogen supply pipe between the hydrogen storage device 15 and the fuel cell 16. The opening and closing of the hydrogen release valves 41 and 42 can be controlled by the control device 20. Further, the hydrogen production device 14 is provided with a pump 43 that returns hydrogen gas to the regenerative dehumidifier 22. Pump 43 can be controlled by control device 20 . Furthermore, a measuring device M11 is provided on the hydrogen inlet side of the hydrogen production device 14. Furthermore, a measuring device M12 is provided on the hydrogen outlet side of the hydrogen storage device 15. Measuring devices M11 and M12 are measuring devices that monitor the amount of hydrogen and hydrogen pressure. The measured values of these measuring instruments M11 and M12 are sent to the control device 20.

A heat medium path 50 is provided to adjust the temperature of each part of the hydrogen utilization system 1, such as the hydrogen production device 14, the hydrogen storage device 15, and the fuel cell 16. Hot water or cold water is circulated in the heat medium path 50 as a heat medium. The temperature of the heat medium in the electrolytic cell 21 of the hydrogen production device 14 is measured by a measuring device M21. The temperature of the heat medium in the alloy tank 23 of the hydrogen storage device 15 is measured by a measuring device M22. The temperature of the heat medium in the heat exchanger 25 of the fuel cell 16 is measured by a measuring device M23. The temperature of the heat medium of the heating device 17 is measured by a measuring device M24. The temperature of the heat medium of the cooling device 18 is measured by a measuring device M25. The temperature of the heat medium of the heat load 19 is measured by a measuring device M26. The measured values of these measuring instruments M21 to M26 are sent to the control device 20. In addition, settings for cooling by operating the cooling device 18, settings for electrolytic current in the hydrogen production device 14, storage and release of hydrogen in the hydrogen storage device 15 by settings for the heating device 17, and settings for the power generation amount of the fuel cell 16. can be controlled by the control device 20 based on the operating schedule prepared on the previous day or in real time.

The control device 20 performs the following control in each state according to the measured value of the measuring device.

When starting up the hydrogen production device 14, the control device 20 applies an electrolytic current to the electrolytic cell 21 so that the hydrogen pressure is 1 MPa or less and the pressure is as high as possible in order to shorten the startup time and improve dehumidification performance. Set. Then, before the hydrogen release valve 41 becomes open, the control device 20 starts brine operation, starts heat exchange, cools the alloy tank 23, and makes it possible to adsorb hydrogen. Then, when the hydrogen release valve 41 is in the open state, the control device 20 sets the electrolytic current to the planned output value and causes the electrolytic cell 21 to generate hydrogen.

When performing regenerative operation of the dehumidifier of the hydrogen production device 14, the control device 20 measures the cumulative operating time of the regenerative dehumidifier 22. Then, when the cumulative operating time of the regenerative dehumidifier 22 exceeds a predetermined time, the control device 20 switches to the line of the other regenerated dehumidifier and dehumidifies the generated hydrogen gas. Then, the control device 20 operates the pump 43 to heat and regenerate the dehumidifier to be regenerated using the heater. Then, the control device 20 stops the pump 43 when the regeneration is completed. In addition, when dehumidifying hydrogen gas when heating and regenerating a certain dehumidifier out of a plurality of dehumidifiers, the control device 20 selects a dehumidifier that is different from the dehumidifier that is being regenerated. Dehumidify hydrogen gas by switching to a dehumidifier that has already been used.

When starting up the fuel cell 16, the control device 20 activates the brine operation of the hydrogen storage device 15, heats the alloy tank 23, and releases hydrogen. Then, the control device 20 opens the hydrogen release valve 42 and starts the fuel cell 16. Then, the control device 20 sets the active power output command to the planned output value, and causes the fuel cell 16 to output the power of the planned value.

When starting and stopping the cooling device 18, the control device 20 monitors the temperature of the heat medium at the entrance of the fuel cell 16 using a measuring device M23, or monitors the temperature of the heating medium at the entrance of the electrolytic cell 21 using a measuring device M21. The temperature of the heat medium is monitored, and when the temperature of the heat medium exceeds a predetermined temperature, the cooling device 18 is activated to perform cooling. Furthermore, when the temperature of the heat medium in the fuel cell 16 or the temperature of the heat medium in the electrolytic cell 21 falls below a predetermined temperature, the cooling device 18 is stopped.

FIG. 3A is an explanatory diagram of the operation of the cooling device 18 in the hydrogen utilization system according to the embodiment of the present invention. In FIG. 3A, the horizontal axis shows the temperature of the heating medium at the entrance of the fuel cell 16, the temperature of the heating medium in the electrolyzer 21, or the tank pressure of the alloy tank 23, and the vertical axis shows the setting state of the cooling device 18 (ON or OFF). ) is shown. As shown in FIG. 3A, the temperature or pressure at the start of the cooling device 18 is set higher than the temperature or pressure at the time the cooling device 18 is stopped, and the temperature or pressure at the start of the cooling device 18 and the cooling device It is designed to have a hysteresis characteristic depending on the temperature or pressure at the time of stopping No. 18.
FIG. 3B is an explanatory diagram of the operation of the heating device 17 in the hydrogen utilization system according to the embodiment of the present invention. In FIG. 3B, the horizontal axis shows the tank pressure of the alloy tank 23, and the vertical axis shows the setting state (ON or OFF) of the heating device 17. As shown in FIG. 3B, the tank pressure of the alloy tank 23 at the time of starting the heating device 17 is set lower than the tank pressure at the time of stopping the heating device 17, and the pressure at the time of starting the heating device 17 and the heating device It is designed to have a hysteresis characteristic with the pressure at the time of stop of 17.

When storing the alloy tank 23, the control device 20 monitors the entrance temperature of the alloy tank 23 with the measuring device M22, and when the temperature exceeds a predetermined temperature, starts the cooling device 18 to perform cooling. Further, when the temperature of the heat medium in the alloy tank 23 falls below a predetermined temperature, the control device 20 stops the cooling device 18.

Furthermore, when the alloy tank 23 is discharged, the control device 20 monitors the entrance temperature of the alloy tank 23 with the measuring device M22, and when the temperature falls below a predetermined temperature, starts the heating device 17 to perform heating. Further, when the temperature of the heat medium in the alloy tank 23 exceeds a predetermined temperature, the control device 20 stops the heating device 17 and further starts the cooling device 18 for cooling.
Further, the control device 20 controls the supply of power from the renewable energy power source to the load equipment in the building or the charging of the power supplied from the renewable energy power source, depending on the power demand of the building. For example, even if the amount of power generated by the renewable energy power source 11 fluctuates with respect to the power demand of the load equipment in the building, the control device 20 controls the renewable energy power source 11 by discharging or charging the storage battery 12. It is possible to compensate for fluctuations in the amount of power generated.

Next, energy management in the hydrogen utilization system 1 according to the embodiment of the present invention will be explained. In the hydrogen utilization system 1 according to the embodiment of the present invention, the amount of electricity generated and the demand for the next day based on renewable energy are predicted on the previous day and an operation plan is drawn up. Operation planning is done the day before, so when the actual day arrives, if the weather does not go as expected, power generation from solar, wind, etc. may not go as planned, or power demand forecasts may fail. However, electricity demand may not be as expected. Real-time control is performed to deal with deviations from predictions. In addition, in this embodiment, monitoring and control are performed in an integrated manner like other building equipment using a smart BEMS (Building Energy Management System), which is an energy management system for buildings.

FIG. 4 is a flowchart showing the operation planning process in the hydrogen utilization system according to the embodiment of the present invention.
(Step S1) First, the operator sets a target value of the maximum demand power of the building in the control device 20, and advances the process to step S2.
(Step S2) Next, the operator sets optimization conditions in the control device 20, and advances the process to step S3. The optimization conditions can be selected from "minimum energy cost,""minimum primary energy," and "minimum CO2 emissions."
(Step S3) The control device 20 acquires weather forecast data and past building power/heat demand performance data, and advances the process to step S4.
(Step S4) The control device 20 predicts the power generation of the renewable energy power source 11 and the demand of the power load 13 using weather forecast data and past performance data of power/heat demand of the building for any time period. The prediction and the demand prediction of the heat load 19 are performed, and the process proceeds to step S5. As the arbitrary time period, for example, a total of 96 time periods are assumed, including three times a day: the night before, the morning of the day, and the afternoon of the day, for 48 hours in 30-minute units.
(Step S5) The control device 20 uses the set optimization conditions to formulate an operation output plan for each facility in each time period based on the power generation prediction and demand prediction results.
(Step S6) The control device 20 verifies whether the operating output plan of each facility is optimized, and if it is not optimized (step S6: No), returns the process to step S4, and Reset the equipment's operating output plan.
(Step S7) If an optimized operation plan is created by repeating the processes from step S4 to step S6 (step S6: Yes), the control device 20 will control each part according to this operation plan at a later date.

FIG. 5 is a flowchart showing an overview of operation control of the entire hydrogen utilization system according to the embodiment of the present invention.
(Step S101) The control device 20 determines whether or not the electric power is surplus or surplus, and hydrogen is to be produced. If hydrogen production processing is to be performed (step S101: Yes), the process proceeds to step S102; if hydrogen production processing is not to be performed (step S101: No), hydrogen production stop processing is performed (step S105), The process advances to step S103.
(Step S102) The control device 20 performs a hydrogen production process and a hydrogen storage process, and advances the process to step S103.
(Step S103) The control device 20 determines whether or not to perform hydrogen power generation, as it is expected that there will be a shortage or shortage of electric power. If hydrogen power generation is to be performed (step S103: Yes), the process proceeds to step S104, and if hydrogen power generation is not to be performed (step S103: No), a hydrogen power generation stop process is performed (step S106), and the process is continued. Return to step S101.
(Step S104) The control device 20 performs a hydrogen release process and a hydrogen power generation process, and returns the process to step S101.

In real-time control, there may be a surplus of power or a shortage of power depending on the operation plan. In the hydrogen production process and the hydrogen storage process (step S102), when electricity is surplus or expected to become surplus, hydrogen is produced in the hydrogen production device 14, and the produced hydrogen is transferred to the alloy in the hydrogen storage device 15. It is stored in the tank 23. In addition, in the hydrogen release process and the hydrogen power generation process (step S104), when the electric power is insufficient or expected to be insufficient, hydrogen is released from the alloy tank 23, and this hydrogen is used to drive the fuel cell 16. , generate electricity.

FIG. 6 is a flowchart showing the hydrogen production process and hydrogen storage process in step S102 in the hydrogen utilization system according to the embodiment of the present invention. FIG. 6A is a flowchart illustrating hydrogen production processing and hydrogen storage processing. FIG. 6B is a flowchart illustrating hydrogen production stop processing.
Note that the predetermined temperatures T1 and T2 are temperature ranges corresponding to the temperature of the electrolytic cell 21 suitable for producing hydrogen in the hydrogen production device 14. The predetermined pressures P1 and P2 are corresponding pressure ranges of the pressure of the alloy tank 23 suitable for storing hydrogen. The temperatures T1 and T2 and the pressures P1 and P2 are optimally set in advance by conducting experiments, simulations, and the like.

First, explanation will be given with reference to the flowchart of FIG. 6A.
(Step S201) The control device 20 determines whether the pressure in the alloy tank 23 of the hydrogen storage device 15 exceeds a predetermined pressure P1. If the pressure in the alloy tank 23 exceeds the predetermined pressure P1 (step S201: Yes), the process proceeds to step S202, and if the pressure in the alloy tank 23 does not exceed the predetermined pressure P1 (step S201: Yes), the process proceeds to step S202. S201: No), the process advances to step S203.
(Step S202) The control device 20 starts the cooling device 18 to cool the inside of the alloy tank, and advances the process to step S213.
(Step S203) The control device 20 determines whether the pressure in the alloy tank 23 of the hydrogen storage device 15 has fallen below a predetermined pressure P2. When the pressure of the alloy tank 23 of the hydrogen storage device 15 is lower than the predetermined pressure P2 (step S203: Yes), the process advances to step S204, and the pressure of the alloy tank 23 of the hydrogen storage device 15 is lower than the predetermined pressure P2. If it is not below (step S203: No), the process advances to step S205.
(Step S214) The control device 20 stops the cooling device 18 and advances the process to step S205.

(Step S205) The control device 20 determines whether the hydrogen production device 14 is activated. If the hydrogen production device 14 is not activated (step S205: No), the process proceeds to step S206, and if the hydrogen production device 14 is activated (step S202: Yes), the process proceeds to step S207.
(Step S206) The control device 20 starts up the hydrogen production device 14, and advances the process to step S207.
(Step S207) The control device 20 sets the electrolytic current of the electrolytic cell 21 of the hydrogen production device 14, performs water electrolysis operation, and advances the process to step S208.
(Step S208) The control device 20 determines whether the cumulative operating time of the regenerative dehumidifier 22 of the hydrogen production device 14 exceeds a predetermined threshold t0. Note that the threshold value t0 is preset as a value of cumulative driving time that allows optimal driving. If the cumulative driving time exceeds the predetermined threshold t0 (step S208: Yes), the process proceeds to step S209, and if it does not exceed the predetermined threshold (step S208: No), the process proceeds to step S210.
(Step S209) The control device 20 switches to a dehumidifier on another line, performs regeneration operation of the dehumidifier, and advances the process to step S207.
(Step S210) The control device 20 determines whether the temperature of the electrolytic cell 21 exceeds a predetermined temperature T1. If the temperature of the electrolytic cell 21 exceeds the predetermined temperature T1 (step S210: Yes), the process proceeds to step S211, and if the temperature does not exceed the predetermined temperature T1 (step S210: No), the process continues. The process proceeds to step S212.
(Step S211) The control device 20 starts the cooling device 18 to cool the inside of the system, and advances the process to step S212.
(Step S212) The control device 20 determines whether the temperature of the electrolytic cell 21 has fallen below a predetermined temperature T2. If the temperature of the electrolytic cell 21 is below the predetermined temperature T2 (step S212: Yes), the process proceeds to step S213, and if the temperature of the electrolytic cell 21 is not below the predetermined temperature T2 (step S212: Yes), the process proceeds to step S213. S212: No), the process exits the hydrogen production process and hydrogen storage process and returns to the main process.
(Step S213) The control device 20 stops the cooling device 18, exits the hydrogen production process and hydrogen storage process, and returns to the main process.

Next, the hydrogen production stop processing will be described with reference to the flowchart in FIG. 6B.
(Step S215) The control device 20 determines whether or not the water electrolysis operation is being started in the hydrogen production device 14. If the water electrolysis operation is being started in the hydrogen production device 14 (step S215: Yes), the process advances to step S216. If the water electrolysis operation is not activated (step S215: No), the process exits from the hydrogen production stop process and returns to the main process.
(Step S216) If the water electrolysis operation is in progress, the control device 20 stops the water electrolysis operation. Then, the process exits from the hydrogen production stop process and returns to the main process.

FIG. 7 is a flowchart showing the hydrogen release process and hydrogen power generation process in step S104 in the hydrogen utilization system according to the embodiment of the present invention.
FIG. 7A is a flowchart illustrating the hydrogen release process and the hydrogen power generation process. FIG. 7B is a flowchart illustrating hydrogen power generation stop processing.
Note that the predetermined temperatures T5 and T6 are temperature ranges corresponding to the temperature of the fuel cell at which the fuel cell 16 can efficiently perform power generation operation. The predetermined pressures P3 and P4 are corresponding pressure ranges of the alloy tank 23 pressure suitable for releasing hydrogen. The temperatures T5 and T6 and the pressures P3 and P4 are optimally set in advance by conducting experiments, simulations, and the like.

First, explanation will be given with reference to the flowchart of FIG. 7A.
(Step S301) The control device 20 determines whether the pressure in the alloy tank 23 has fallen below a predetermined pressure P3. If the pressure in the alloy tank 23 is below the predetermined pressure P3 (step S301: Yes), the process proceeds to step S302, and if the pressure in the alloy tank 23 is not below the predetermined pressure P3 (step S301), the process proceeds to step S302. :No), the process advances to step S303.
(Step S302) The control device 20 operates (starts up) the heating device 17 to heat the heat medium, and advances the process to step S303.
(Step S303) The control device 20 determines whether the pressure in the alloy tank 23 exceeds a predetermined pressure P4. If the pressure in the alloy tank 23 exceeds the predetermined pressure P4, the process advances to step S304. If the pressure in the alloy tank 23 does not exceed the predetermined pressure P4 (step S303: No), the process advances to step S305.
(Step S304) The control device 20 stops the heating by the heating device 17, and advances the process to step S305.

(Step S305) The control device 20 determines whether the fuel cell 16 is being activated. If the fuel cell 16 is not activated (step S305: No), the process proceeds to step S306, and if the fuel cell 16 is activated (step S305: Yes), the process proceeds to step S307.
(Step S306) The control device 20 starts up the fuel cell 16, and advances the process to step S307.
(Step S307) The control device 20 sets the power output of the fuel cell 16, operates the fuel cell 16 to generate electricity, and advances the process to step S308.
(Step S308) The control device 20 determines whether the heat medium temperature of the fuel cell 16 exceeds a predetermined temperature T5. If the heat medium temperature of the fuel cell 16 exceeds the predetermined temperature T5 (step S309: Yes), the process advances to step S306, and if the heat medium temperature of the fuel cell 16 does not exceed the predetermined temperature T5, the process proceeds to step S306. (Step S308: No), the process advances to Step S310.

(Step S309) The control device 20 starts the cooling device 18 to cool it down.
(Step S310) The control device 20 determines whether the heat medium temperature of the fuel cell 16 has fallen below a predetermined temperature T6. If the heating medium temperature of the fuel cell 16 is below the predetermined temperature T6 (step S310: Yes), the process proceeds to step S311, and if the heating medium temperature of the fuel cell 16 is not below the predetermined temperature T6, the process proceeds to step S311. (Step S310: No), the process exits the hydrogen release process and the hydrogen power generation process and returns to the main process.
(Step S311) The control device 20 stops the cooling device 18. Then, the process exits the hydrogen release process and the hydrogen power generation process and returns to the main process.
Next, the hydrogen power generation stop process will be described with reference to the flowchart in FIG. 7B.
(Step S315) The control device 20 determines whether the fuel cell 16 is being activated. If the fuel cell 16 is being activated (step S315: Yes), the process advances to step S316. If the fuel cell 16 is not activated (step S315: No), the process exits from the hydrogen power generation stop process and returns to the main process.
(Step S316) If the fuel cell 16 is being activated, the operation of the fuel cell 16 is stopped. Then, the process exits from the hydrogen power generation stop process and returns to the main process.

As explained above, in the hydrogen utilization system 1 according to the embodiment of the present invention, hydrogen can be stored using a titanium/iron-based hydrogen storage alloy that does not fall under the category of dangerous substances under the Fire Service Act, and hydrogen can be stored inside buildings or Hydrogen can be produced, stored, and used safely and compactly on-site. Additionally, the entire system can be operated under optimal control, allowing surplus power from renewable energy to be used with high efficiency. Further, by providing the cooling device 18, temperature ranges can be effectively managed without using energy.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and includes designs within the scope of the gist of the present invention.

11... Renewable energy power source, 12... Storage battery, 13... Power load, 14... Hydrogen production device, 15... Hydrogen storage device, 16... Fuel cell, 17... Heating device, 18... Cooling device, 19... Heat load, 20... Control device

Claims (7)

A hydrogen-utilizing power supply system that supplies electric power generated using hydrogen as at least part of the electric power supplied to a load,
A hydrogen production device that produces hydrogen by electrolyzing water accumulated in an electrolyzer using power obtained from renewable energy or power from a commercial power source;
a hydrogen storage device that stores the produced hydrogen in an alloy tank sealed with a hydrogen storage alloy;
a fuel cell that generates electricity using hydrogen stored in the hydrogen storage device;
a cooling device;
a heating device;
a heat medium path for recovering exhaust heat from the electrolyzer of the hydrogen production device;
Determine whether the temperature or pressure of any one of the electrolytic cell, the alloy tank, and the fuel cell exceeds a reference temperature or reference pressure, and if the temperature or pressure exceeds the reference temperature or reference pressure, the reference temperature or pressure is determined. a control device that causes the cooling device to cool any one of the electrolytic cell, the alloy tank, and the fuel cell beyond the
The control device is configured to recover waste heat generated from the electrolytic cell through the heat medium path in response to activation of the hydrogen production device, and to recover the heat using the heating device when hydrogen is released from the alloy tank. heating the alloy tank by circulating the medium path;
A hydrogen-based power supply system with The hydrogen-utilizing power supply system according to claim 1, wherein the control device heats the alloy tank using exhaust heat of the fuel cell when releasing hydrogen from the alloy tank. The hydrogen-based power supply system includes:
Equipped with a heat load device that can exchange heat with building equipment,
The control device heats or cools any one of the electrolytic cell, the alloy tank, and the fuel cell by heat exchange with the heat load device.
The hydrogen-utilizing power supply system according to claim 1 or 2. The hydrogen-based power supply system has a storage battery that charges and discharges power,
The control device controls the supply of power from the renewable energy power source to the load equipment in the building or the charging of the power supplied from the renewable energy power source in accordance with the power demand of the building. 3. The hydrogen-utilizing power supply system according to any one of 3. The hydrogen-utilizing power supply system includes a plurality of lines of dehumidifiers in the hydrogen production device, which dehumidifies moisture in the hydrogen gas generated from the electrolytic cell, and which regenerates when the dehumidifier is heated and regenerated. Dehumidify hydrogen by switching to a different dehumidifier that has been regenerated,
The hydrogen-utilizing power supply system according to any one of claims 1 to 4. A hydrogen-based power supply method that supplies power generated using hydrogen as at least part of the power supplied to a load, the method comprising:
A step of electrolyzing water accumulated in an electrolyzer using power obtained from renewable energy or power from a commercial power source to produce hydrogen using a hydrogen production device ;
storing the produced hydrogen in an alloy tank containing a hydrogen storage alloy;
generating electricity with a fuel cell using the stored hydrogen;
Determine whether the temperature or pressure of any one of the electrolytic cell, the alloy tank, and the fuel cell exceeds a reference temperature or reference pressure, and if the temperature or pressure exceeds the reference temperature or reference pressure, the reference temperature or pressure is determined. a step of cooling any one of the electrolytic cell, the alloy tank, and the fuel cell beyond the above with a cooling device;
When the exhaust heat generated from the electrolyzer is recovered by the heat medium path in response to activation of the hydrogen production device and hydrogen is released from the alloy tank , the heating device is used to circulate the heat medium path. heating the alloy tank at
A method of supplying electricity using hydrogen. 7. The method according to claim 6, further comprising the step of determining whether the pressure of the alloy tank is lower than a reference pressure, and heating the alloy tank by exhaust heat of a heating device or a fuel cell if the pressure is lower than the reference pressure. How to supply electricity using hydrogen.

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