Hydrogen production system

Abstract

To appropriately deal with the supply stop of electric power from renewable energy, in a hydrogen production system for generating / storing hydrogen using electric power from renewable energy.SOLUTION: The hydrogen production system for producing / storing hydrogen, comprises an electrolysis stack receiving electric power generated by renewable energy to electrolyze steam to generate hydrogen, a hydrogen tank for storing the hydrogen generated, an insulation heater for keeping the electrolysis stack warm, and a fuel cell stack that generates electric power using the hydrogen stored in the hydrogen tank and can supply electric power to the insulation heater and to outside of the system.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a hydrogen production system. [Background technology]

[0002] Conventionally, hydrogen production systems are known that store hydrogen produced by electrolysis of water vapor in a hydrogen tank. For example, Patent Document 1 describes a system that includes an electrolysis cell that receives grid power and produces hydrogen by electrolysis, and determines whether or not to preheat the electrolysis cell based on the conversion efficiency from power to hydrogen, the unit price of power, and the unit price of hydrogen. Since electrolysis is performed in a high-temperature state, it takes time for the electrolysis cell to start operating when the system is started from a low-temperature state, but preheating allows the electrolysis cell to start operating quickly. On the other hand, when it is determined that preheating is unnecessary, preheating is not performed, thereby suppressing unnecessary energy consumption.

[0003] Patent Document 2 describes a system that normally receives surplus power from a main power source, generates hydrogen through electrolysis, and stores it in a hydrogen tank, and in an emergency when the main power source experiences a power outage due to some abnormality, supplies the hydrogen stored in the hydrogen tank to a fuel cell to generate electricity. With this system, electricity can be supplied from the fuel cell to devices that require power in an emergency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-170164 A [Patent Document 2] Japanese Patent Application Publication No. 5-146095 Summary of the Invention [Problem to be solved by the invention]

[0005] In the hydrogen production system described above, it is conceivable to generate hydrogen by receiving a supply of electricity generated by renewable energy. However, since the power supply of renewable energy is more unstable than that of a grid power supply and there is a high possibility of the power supply being stopped, it is necessary to respond appropriately to the stoppage of the power supply.

[0006] A primary object of the present disclosure is to provide a hydrogen production system that generates and stores hydrogen using electricity from renewable energy sources, capable of appropriately dealing with interruptions in the supply of electricity from renewable energy sources. [Means for solving the problem]

[0007] In order to achieve the above-mentioned main object, the present disclosure has adopted the following means.

[0008] The hydrogen production system of the present disclosure comprises: A hydrogen production system that produces and stores hydrogen, an electrolysis stack that receives electricity generated by renewable energy sources and electrolyzes water vapor to produce hydrogen; A hydrogen tank for storing the generated hydrogen; a heater for keeping the electrolysis stack warm; a fuel cell stack capable of generating electricity using hydrogen stored in the hydrogen tank and supplying the electric power to the heater and to an external device of the system; The gist of the invention is to provide the following:

[0009] The hydrogen production system disclosed herein includes a fuel cell stack that generates electricity using hydrogen produced by an electrolysis stack and stored in a hydrogen tank, and that can supply power to a heater that keeps the electrolysis stack warm and to the outside of the system. This allows the electrolysis stack to be kept warm by the heater when the operation of the electrolysis stack is stopped, so that the next time the electrolysis stack is operated, it can be started quickly. In addition, since the fuel cell stack can supply power to the outside of the system, it is possible to supply necessary power to the outside even when the power supply from renewable energy is stopped. Therefore, in a hydrogen production system that produces and stores hydrogen using power from renewable energy, it is possible to appropriately respond to a stop in the supply of power from renewable energy. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram of a hydrogen production system 10. FIG. [Diagram 2] FIG. 2 is an explanatory diagram of the operation of the hydrogen production system 10 during normal operation of the electrolysis stack 20. [Diagram 3] FIG. 2 is an explanatory diagram of the operation of the hydrogen production system 10 when the electrolysis stack 20 is out of operation. [Figure 4] FIG. 2 is an explanatory diagram of the operation of the hydrogen production system 10 during a power outage. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] An embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic diagram of a hydrogen production system 10. The hydrogen production system 10 includes an electrolysis stack (SOEC) 20, a heat retention heater 25, a fuel cell stack (SOFC) 30, a water supply system 40, an air supply system 50, a hydrogen recovery system 60, and a control device 80. The electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30 are housed in a case 12 having thermal insulation properties. The case 12 also houses an evaporator 26, heaters 28a, 28b, and 28c, a heat exchanger 29, and the like, in addition to the electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30. In the hydrogen production system 10, electricity generated by renewable energy such as solar power (hereinafter, renewable energy electricity RE) is adjusted by a power regulator 14 to the required power and supplied to each part of the hydrogen production system 10.

[0012] The electrolysis stack (electrolysis cell stack) 20 includes a plurality of solid oxide type single cells each including an electrolyte 20a, a hydrogen electrode 20b arranged on one side of the electrolyte 20a, and an oxygen electrode 20c arranged on the other side of the electrolyte 20a. The electrolysis stack 20 performs an electrolysis operation in which water vapor is electrolyzed to generate hydrogen and oxygen while receiving power from renewable energy power RE. The electrolysis operation is performed at a high temperature of 600°C or higher, for example, 700°C.

[0013] One end of a hydrogen electrode piping 21 is connected to the inlet of the hydrogen electrode 20b of the electrolysis stack 20, and one end of a hydrogen electrode off-gas piping 23 is connected to the outlet of the hydrogen electrode 20b. The other end of the hydrogen electrode piping 21 is connected to an evaporator 26. The hydrogen electrode piping 21 is also provided with a heater 28b, such as a sheath heater. The heater 28b heats the water vapor supplied from the hydrogen electrode piping 21 to the hydrogen electrode 20b. The other end of the hydrogen electrode off-gas piping 23 is connected to a condenser 64 of the hydrogen recovery system 60.

[0014] One end of the oxygen electrode pipe 22 is connected to the inlet of the oxygen electrode 20c of the electrolysis stack 20, and one end of the oxygen electrode off-gas pipe 24 is connected to the outlet of the oxygen electrode 20c. The other end of the oxygen electrode pipe 22 is connected to an air supply pipe 51 of an air supply system 50. In addition, a heater 28c such as a sheath heater and a heat exchanger 29 are provided in series in the oxygen electrode pipe 22. The heat exchanger 29 exchanges heat between the air (oxidant gas) flowing through the oxygen electrode pipe 22 and the oxygen electrode off-gas flowing through the oxygen electrode off-gas pipe 24. The oxygen electrode off-gas flowing through the oxygen electrode off-gas pipe 24 is heat exchanged in the heat exchanger 29 and then discharged to the outside of the case 12. The heater 28c heats the air supplied from the oxygen electrode pipe 22 to the oxygen electrode 20c.

[0015] The warm-keeping heater 25 is configured as an electric heater such as a sheath heater, and is provided integrally with the outer side of the electrolysis stack 20 so as to keep the electrolysis stack 20 warm. In this embodiment, the fuel cell stack 30 is disposed adjacent to the warm-keeping heater 25. Therefore, the warm-keeping heater 25 is disposed so as to be sandwiched between the electrolysis stack 20 and the fuel cell stack 30.

[0016] The fuel cell stack (fuel cell stack) 30 includes a plurality of solid oxide type unit cells, each including an electrolyte (not shown), a fuel electrode arranged on one side of the electrolyte, and an air electrode arranged on the other side of the electrolyte. The fuel cell stack 30 performs a power generation operation by electrochemical reaction between hydrogen supplied from a hydrogen recovery system 60 and air (oxidant gas) supplied from an air supply system 50. The fuel cell stack 30 is capable of starting up with power from a battery (not shown) and starting a power generation operation.

[0017] One end of the fuel electrode pipe 31 is connected to the inlet of the fuel electrode of the fuel cell stack 30, and the fuel electrode off-gas pipe 33 is connected to the outlet of the fuel electrode. The other end of the fuel electrode pipe 31 is connected to the hydrogen discharger 62 of the hydrogen recovery system 60. The other end of the fuel electrode off-gas pipe 33 is connected to the hydrogen electrode pipe 21 between the evaporator 26 and the heater 28b. Therefore, the fuel electrode off-gas of the fuel cell stack 30 can be circulated and supplied from the hydrogen electrode pipe 21 to the hydrogen electrode 20b of the electrolysis stack 20. In addition, one end of the air electrode pipe 32 is connected to the inlet of the air electrode of the fuel cell stack 30, and the air electrode off-gas pipe (not shown) is connected to the outlet of the air electrode. The other end of the air electrode pipe 32 is connected to the air supply pipe 53 of the air supply system 50. The air electrode off-gas flowing through the air electrode off-gas pipe of the fuel cell stack 30 is heat exchanged in the heat exchanger 29 and then discharged outside the case 12. It is also possible to provide a heat exchanger other than the heat exchanger 29, and in this heat exchanger, heat may be exchanged between the air electrode off-gas flowing through the air electrode off-gas piping of the fuel cell stack 30 and the air flowing through the air electrode piping 32.

[0018] The water supply system 40 includes a water tank 41 for storing water, a water supply pipe 42 having one end connected to the water tank 41 and the other end connected to the evaporator 26, and a water pump 44 provided on the water supply pipe 42. The water in the water tank 41 is pumped (supplied) to the evaporator 26 through the water supply pipe 42 by operation of the water pump 44. The evaporator 26 is provided with a heater 28a such as a sheath heater. The water supplied to the evaporator 26 is evaporated in the evaporator 26 by heat from the heater 28a to become water vapor, passes through the hydrogen electrode pipe 21, is heated to a required temperature by the heater 28b, and is then supplied to the hydrogen electrode 20b of the electrolysis stack 20.

[0019] The air supply system 50 includes an air supply pipe 51, one end of which is connected to a filter (not shown) and the other end of which is connected to the oxygen electrode pipe 22, an air blower 52 installed in the air supply pipe 51, an air supply pipe 53, one end of which is connected to a filter (not shown) and the other end of which is connected to the air electrode pipe 32, and an air blower 54 installed in the air supply pipe 53. Air sucked into the air supply pipe 51 through the filter by driving the air blower 52 flows into the oxygen electrode pipe 22, where it is heat exchanged in the heat exchanger 29 and heated by the heater 28c, and then supplied to the oxygen electrode 20c of the electrolysis stack 20. Air sucked into the air supply pipe 53 through the filter by driving the air blower 54 flows into the air electrode pipe 32, where it is heat exchanged in the heat exchanger 29 and then supplied to the air electrode of the fuel cell stack 30.

[0020] The hydrogen recovery system 60 includes a hydrogen tank 61 for storing hydrogen, a hydrogen releaser 62 for releasing hydrogen stored in the hydrogen tank 61, a recovery pipe 63 having one end connected to the hydrogen tank 61, a condenser 64 for condensing water vapor contained in the anode off-gas, and a compression pump 65 for compressing hydrogen in the recovery pipe 63 and sending it to the hydrogen tank 61. The hydrogen releaser 62 includes a switching valve for switching on / off of hydrogen release (supply) to each release destination such as the hydrogen utilization device HU and the fuel cell stack 30 (anode pipe 31), and a flow rate adjustment valve for adjusting the amount of hydrogen released (supplied) to each release destination. The condenser 64 has a heat exchange flow path capable of exchanging heat with water, the other end of the hydrogen electrode off-gas pipe 23 is connected to the inlet of the heat exchange flow path, and the other end of the recovery pipe 63 is connected to the outlet of the heat exchange flow path. The hydrogen electrode off-gas containing hydrogen and water vapor that has flowed through the hydrogen electrode off-gas piping 23 has the water vapor condensed by heat exchange in the heat exchange passage of the condenser 64, and is then recovered in the hydrogen tank 61 through the recovery piping 63 by driving the compression pump 65. In addition, the condensed water obtained by condensing the hydrogen electrode off-gas in the condenser 64 is stored in the water tank 41 described above. The water stored in the water tank 41 is used to generate water vapor for electrolysis.

[0021] The control device 80 is configured as a microprocessor with a CPU as its core, and includes, in addition to the CPU, a ROM for storing a processing program, a RAM for temporarily storing data, and an input / output port. Temperature signals from a temperature sensor or the like installed near the electrolysis stack 20, flow rate signals from a flow rate sensor installed in the hydrogen electrode pipe 21, a flow rate sensor installed in the oxygen electrode pipe 22, and a flow rate sensor installed in the fuel electrode pipe 31, and the like are input to the control device 80 via an input port. On the other hand, the control device 80 outputs control signals to the heat retention heater 25, the heaters 28a, 28b, 28c, the water pump 44, the air blowers 52, 54, the hydrogen releaser 62, the compression pump 65, and the like via an output port. The control device 80 can be supplied with power from a battery (not shown).

[0022] Next, as the operation of the hydrogen production system 10 of this embodiment configured as described above, the operation during normal operation of the electrolysis stack 20 (see FIG. 2), the operation during suspension of operation of the electrolysis stack 20 (see FIG. 3), and the operation during a power outage when the supply of renewable energy power RE is stopped (see FIG. 4) will be described. For convenience of explanation, FIGS. 2 to 4 show simplified diagrams in which some of the configuration of the hydrogen production system 10 is omitted and the heaters 28a, 28b, and 28c, the water pump 44, and the air blowers 52 and 54 are collectively grouped together as other auxiliary equipment. In addition, the flow of electricity is indicated by dotted arrows, the flow of hydrogen is indicated by solid arrows, and the flow of heat is indicated by hollow arrows.

[0023] As shown in Fig. 2, during normal operation of the electrolysis stack 20, renewable energy power RE is adjusted to the required power by the power regulator 14 and supplied to the electrolysis stack 20, the heat retention heater 25, the compression pump 65, and other auxiliary equipment. The electrolysis stack 20 uses the supplied power to generate hydrogen through steam electrolysis. The generated hydrogen is compressed by the compression pump 65 and stored in the hydrogen tank 61. The hydrogen stored in the hydrogen tank 61 is released by the hydrogen releaser 62 and supplied to the fuel cell stack 30 and the hydrogen utilization device HU.

[0024] During normal operation, the fuel cell stack 30 generates power using the supplied hydrogen and supplies the generated power to the hydrogen releaser 62. In this embodiment, since renewable energy power RE can be supplied to the heat retention heater 25, there is no need to supply power from the fuel cell stack 30 to the heat retention heater 25 during normal operation when renewable energy power RE is being supplied. On the other hand, since the fuel cell stack 30 is adjacent to the heat retention heater 25 and heat generated by power generation in the fuel cell stack 30 is efficiently transferred to the heat retention heater 25, it is possible to reduce power consumption of the heat retention heater 25 for keeping the electrolysis stack 20 warm and improve energy efficiency.

[0025] As shown in Fig. 3, when the electrolysis stack 20 is out of operation, the supply of power to the electrolysis stack 20, the compression pump 65, and other auxiliary devices is suspended. The electrolysis stack 20 is suspended when there is no need to generate hydrogen, for example, when there is a shortage of renewable energy power, such as at night, or when the hydrogen utilization device HU has stopped utilizing hydrogen and sufficient hydrogen is stored in the hydrogen tank 61. In this embodiment, even when the electrolysis stack 20 is out of operation, the renewable energy power RE is adjusted to a required power by the power regulator 14 and supplied to the heat retention heater 25 during a time period when renewable energy power RE is supplied, such as during the daytime. The hydrogen stored in the hydrogen tank 61 is released by the hydrogen releaser 62 and supplied to the fuel cell stack 30.

[0026] Even when the fuel cell stack 30 is not in operation, the fuel cell stack 30 generates electricity using the supplied hydrogen and supplies the generated electricity to the hydrogen releaser 62. In addition, during the time period when the renewable energy electricity RE is not supplied, such as at night, the fuel cell stack 30 also supplies the generated electricity to the heat retention heater 25. Therefore, the heat retention heater 25 is supplied with electricity regardless of day and night, so that the electrolysis stack 20 can be kept warm and maintained at a predetermined high temperature state (for example, 600 to 700°C). In other words, the electrolysis stack 20 during the operation suspension can be maintained at a high temperature state (hot standby) so that the next operation can be started up quickly. During the operation suspension, the heat retention heater 25 is controlled so that the temperature detected by a temperature sensor near the electrolysis stack 20 is set as the target temperature, for example. In addition, the flow rate adjustment valve of the hydrogen releaser 62 may be controlled so that the amount of hydrogen required to generate the electricity required to operate the heat retention heater 25 is supplied to the fuel cell stack 30.

[0027] As shown in Fig. 4, during a power outage, the power supply from the power regulator 14 to the warming heater 25 is stopped. Furthermore, hydrogen stored in the hydrogen tank 61 is released by the hydrogen releaser 62 and supplied to the fuel cell stack 30. The fuel cell stack 30 generates power using the supplied hydrogen and supplies the generated power to the hydrogen releaser 62. That is, the fuel cell stack 30 of this embodiment generates power at all times (continuously) including during normal operation of the electrolysis stack 20, when operation is suspended, during a power outage, etc. Note that in this embodiment, no power is supplied from the fuel cell stack 30 to the warming heater 25 during a power outage.

[0028] In addition, during a power outage, the fuel cell stack 30 supplies the power generated by the emergency operating device EA, so that the emergency operating device EA can be supplied with power to ensure operation in an emergency. That is, in this embodiment, the hydrogen production system 10 can produce and store hydrogen during normal times to enable the hydrogen utilization device HU to utilize hydrogen, while functioning as an emergency power source for BCP (Business Continuity Plan) measures and the like during a power outage. Note that, during a power outage, the flow rate adjustment valve of the hydrogen releaser 62 may be controlled so that the amount of hydrogen required to generate the power required to operate the emergency operating device EA is supplied to the fuel cell stack 30. In addition, in order to allow the hydrogen production system 10 (fuel cell stack 30) to function as an emergency power source during a power outage, it is desirable to calculate the required amount of hydrogen from the amount of power generated by the fuel cell stack 30 based on the power consumption and required operation time of the emergency operating device EA, for example, and operate the hydrogen production system 10 (electrolysis operation of the electrolysis stack 20) ​​so that the amount of hydrogen always remains in the hydrogen tank 61.

[0029] The hydrogen production system 10 described above includes a fuel cell stack 30 that generates electricity using hydrogen produced by the electrolysis stack 20 and stored in the hydrogen tank 61, and is capable of supplying power to the heat retention heater 25 and to the emergency activation device EA (outside the system). This allows the electrolysis stack 20 to be kept warm when the operation of the electrolysis stack 20 is suspended, so that the electrolysis stack 20 can be quickly started the next time it is operated. In addition, the fuel cell stack 30 can supply power to the emergency activation device EA when the power supply from the renewable energy power RE is stopped. Therefore, in a system that generates and stores hydrogen using renewable energy power RE, it is possible to appropriately respond to a stop in the supply of the renewable energy power RE.

[0030] Furthermore, the fuel cell stack 30 can supply power to the warming heater 25 during normal operation and when operation of the electrolysis stack 20 is suspended, and during a power outage, the supply of power to the warming heater 25 is stopped and power is supplied to the emergency actuation device EA. Therefore, during a power outage, priority can be given to the supply of power to external devices that require a power supply, such as the emergency actuation device EA.

[0031] Furthermore, the fuel cell stack 30 is capable of constantly generating power and supplying power to the hydrogen releaser 62. Therefore, when the supply of renewable energy power RE is stopped, the hydrogen releaser 62 can immediately supply the required amount of hydrogen to the fuel cell stack 30, thereby supplying the required power to the emergency operating device EA. In other words, it can function as an emergency power source in the event of a power outage.

[0032] Furthermore, since the heat-insulating case 12 that houses the electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30 is provided, heat generated by power generation in the fuel cell stack 30 can be transferred to the heat retention heater 25 and effectively utilized. This allows the heat retention heater 25 to efficiently keep the electrolysis stack 20 warm.

[0033] In the embodiment described above, the fuel cell stack 30 is disposed adjacent to the warming heater 25, but this is not limiting, and the fuel cell stack 30 may be disposed away from the warming heater 25. For example, the fuel cell stack 30 may be disposed on the hydrogen electrode 20b side in Fig. 1. Alternatively, the fuel cell stack 30 may be disposed away from the electrolysis stack 20, rather than in the vicinity of the electrolysis stack 20.

[0034] In the embodiment, the case 12 accommodates the evaporator 26, the heaters 28a, 28b, 28c, the heat exchanger 29, and the like in addition to the electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30, but is not limited to this and may accommodate at least the electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30. Alternatively, the electrolysis stack 20, the heat retention heater 25, and the fuel cell stack 30 are not limited to being accommodated in the case 12, and for example, the fuel cell stack 30 may be disposed outside the case 12.

[0035] In the embodiment, the fuel cell stack 30 stops supplying power to the warmth heater 25 during a power outage when the supply of renewable energy power RE is stopped, but if power to the emergency actuation device EA can be secured even during a power outage, power may be supplied to the warmth heater 25. Also, while it is possible to supply renewable energy power RE to the warmth heater 25, it is also possible to disable the supply of renewable energy power RE to the warmth heater 25 and supply it from the fuel cell stack 30.

[0036] In the embodiment, the fuel cell stack 30 continuously generates power and supplies power to the hydrogen discharger 62, but this is not limited to the above. For example, the fuel cell stack 30 does not have to continuously generate power. However, in order to enable a rapid supply of power during a power outage, it is preferable that the fuel cell stack 30 continuously generates power. In addition, by making it possible to supply renewable energy power RE to the hydrogen discharger 62, the fuel cell stack 30 does not have to supply power to the hydrogen discharger 62 during time periods when the renewable energy power RE is being supplied, such as during the daytime.

[0037] The correspondence between the main elements of the embodiment and the main elements of the present disclosure described in the section on Means for Solving the Problems will be described below. The electrolysis stack 20 of the embodiment corresponds to the "electrolysis stack" of the present disclosure, the hydrogen tank 61 corresponds to the "hydrogen tank", the heat retention heater 25 corresponds to the "heat retention heater", and the fuel cell stack 30 corresponds to the "fuel cell stack". The hydrogen releaser 62 corresponds to the "release section". The case 12 corresponds to the "case".

[0038] In addition, the correspondence between the main elements of the embodiment and the main elements of the present disclosure described in the Means for Solving the Problem column does not limit the elements of the present disclosure described in the Means for Solving the Problem column, since the embodiment is an example for specifically explaining the form for implementing the present disclosure described in the Means for Solving the Problem column. In other words, the interpretation of the present disclosure described in the Means for Solving the Problem column should be made based on the description in that column, and the embodiment is merely a specific example of the present disclosure described in the Means for Solving the Problem column.

[0039] The above describes the form for implementing the present disclosure using embodiments, but the present disclosure is not limited to these embodiments in any way, and it goes without saying that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure. [Industrial Applicability]

[0040] The present disclosure can be used in the hydrogen production system manufacturing industry and the like. [Explanation of symbols]

[0041] 10 Hydrogen production system, 12 Case, 20 Electrolysis stack (SOEC), 35 Heat retention heater, 30 Fuel cell stack (SOFC), 31 Anode piping (supply path), 61 Hydrogen tank, 62 Hydrogen releaser (release section), RE Renewable energy (renewable energy), EA Emergency activation device (outside the system, external device).

Claims

1. A hydrogen production system that produces and stores hydrogen, an electrolysis stack that receives electricity generated by renewable energy sources and electrolyzes water vapor to produce hydrogen; A hydrogen tank for storing the generated hydrogen; a heater for keeping the electrolysis stack warm; a fuel cell stack capable of generating electricity using hydrogen stored in the hydrogen tank and supplying the electric power to the heater and to an external device of the system; A hydrogen production system comprising:

2. The fuel cell stack is capable of supplying power to the heat retention heater during normal operation and when the electrolysis stack is not in operation, and in the event of a power outage in which power generation by the renewable energy is stopped, the supply of power to the heat retention heater is stopped and power is supplied to outside the system. The hydrogen production system according to claim 1 .

3. a release section capable of releasing hydrogen stored in the hydrogen tank into a hydrogen supply path to the fuel cell stack; The fuel cell stack is capable of constantly generating power and supplying power to the discharge section. The hydrogen production system according to claim 1 or 2.

4. a heat-insulating case that houses the electrolysis stack, the heater, and the fuel cell stack; The hydrogen production system according to claim 1 or 2.

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