Hydrogen production and storage system

Abstract

To provide a hydrogen production pressure accumulation system capable of improving hydrogen production efficiency.SOLUTION: A hydrogen production pressure accumulation system includes a plurality of hydrogen production devices, a buffer tank, a compressor, and a pressure accumulator. A hydrogen supply pressure of each of the hydrogen production devices is measured by a supply pressure gauge. The supply of hydrogen from the corresponding hydrogen production device to the buffer tank is controlled by a plurality of tank supply valves. A control unit opens each of the tank supply valves in a case when the supply pressure measured by each of the supply pressure gauges reaches a first reference pressure.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The embodiments relate to a hydrogen production and storage system.

Background Art

[0002] From the perspective of Sustainable Development Goals (SDGs), in recent years, the development of fuel cell vehicles (FCVs) has been promoted. Hydrogen as fuel can be produced by water electrolysis using natural energy such as solar power generation (PV power generation) and wind power generation. The hydrogen produced in this way is called green hydrogen, and there is increasing interest in storing it in hydrogen stations for use. <00​​​​​​​​​​​​​​​​​​Japanese Patent Publication No. 2004-116544 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The embodiment provides a hydrogen production and storage system that can improve hydrogen production efficiency. [Means for solving the problem]

[0007] The embodiment comprises a plurality of hydrogen production devices, a buffer tank for storing hydrogen supplied from the plurality of hydrogen production devices, a compressor for compressing the hydrogen supplied from the buffer tank, an accumulator for storing the hydrogen compressed by the compressor, a plurality of supply pressure gauges for measuring the hydrogen supply pressure of each hydrogen production device, a plurality of tank supply valves for controlling the supply of hydrogen from the corresponding hydrogen production device to the buffer tank, and a control unit. The control unit controls each of the tank supply valves to open each of the tank supply valves when the supply pressure measured by each of the supply pressure gauges reaches a first reference pressure.

[0008] The embodiment includes a hydrogen production apparatus, a buffer tank for storing hydrogen supplied from the hydrogen production apparatus, a compressor for compressing hydrogen supplied from the buffer tank, an accumulator for storing hydrogen compressed by the compressor, and a pressure-holding valve for controlling the supply of hydrogen from the buffer tank to the compressor. The pressure-holding valve opens when the internal pressure of the buffer tank reaches a fourth reference pressure. [Effects of the Invention]

[0009] According to this embodiment, hydrogen production efficiency can be improved. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 shows a hydrogen production and storage system according to the first embodiment. [Figure 2] Figure 2 shows a hydrogen production and storage system according to the second embodiment. [Figure 3] Figure 3 shows a hydrogen production and storage system according to the third embodiment. [Modes for carrying out the invention]

[0011] The embodiments will be described below with reference to the drawings.

[0012] (First Embodiment) First, the hydrogen production and storage system according to the first embodiment will be described using Figure 1. The hydrogen production and storage system is used, for example, in a hydrogen station for refueling fuel cell vehicles and the like.

[0013] As shown in Figure 1, the hydrogen production and accumulator system 1 comprises hydrogen production devices 2A and 2B, a buffer tank 3, a compressor 4, and an accumulator 5.

[0014] Hydrogen production devices 2A and 2B are configured to produce hydrogen. Hydrogen production devices 2A and 2B may be configured to produce hydrogen by water electrolysis. The electricity used for water electrolysis is not particularly limited, but may be electricity derived from renewable energy sources such as solar power or wind power.

[0015] The hydrogen production and storage system 1 according to this embodiment may include two hydrogen production devices 2A and 2B. The two hydrogen production devices 2A and 2B will be referred to as the first hydrogen production device 2A and the second hydrogen production device 2B and will be described below. Hydrogen produced by the first hydrogen production device 2A is supplied to the buffer tank 3 via the first tank supply line 12A, which will be described later. Hydrogen produced by the second hydrogen production device 2B is supplied to the buffer tank 3 via the second tank supply line 12B, which will be described later.

[0016] The buffer tank 3 is supplied with hydrogen from the first hydrogen production device 2A and the second hydrogen production device 2B. The buffer tank 3 receives and stores the supplied hydrogen. The hydrogen stored in the buffer tank 3 is supplied to the compressor 4 via the compressor supply line 15, which will be described later. By storing hydrogen in the buffer tank 3, the supply pressure of hydrogen to the compressor 4 is stabilized.

[0017] The compressor 4 receives hydrogen supplied from the buffer tank 3 and compresses it, increasing the hydrogen pressure. The compressor 4 discharges hydrogen at a flow rate corresponding to the amount of hydrogen produced by the hydrogen production devices 2A and 2B. If the discharge flow rate is too high, the internal pressure of the buffer tank 3 will decrease, potentially disrupting the balance with the production volume of the hydrogen production devices 2A and 2B. On the other hand, if the discharge flow rate is too low, the internal pressure of the buffer tank 3 will not decrease as easily, potentially reducing the production capacity of the hydrogen production devices 2A and 2B. Therefore, the discharge rate from the compressor 4 is set to maintain a balance with the production volume of the hydrogen production devices 2A and 2B.

[0018] The accumulator 5 is supplied with hydrogen compressed by the compressor 4. The supplied hydrogen is stored in the accumulator 5 at a predetermined pressure.

[0019] As shown in Figure 1, the hydrogen production accumulator system 1 according to this embodiment includes two supply pressure gauges 11A and 11B, two tank supply lines 12A and 12B, two tank supply valves 13A and 13B, an internal pressure gauge 14, a compressor supply line 15, a compressor supply valve 16, a pressure relief valve 17, and a control unit 18.

[0020] The two supply pressure gauges 11A and 11B will be referred to as the first supply pressure gauge 11A and the second supply pressure gauge 11B, respectively, and will be described below. The first supply pressure gauge 11A is configured to measure the supply pressure of the first hydrogen production device 2A. The measured supply pressure value obtained by the first supply pressure gauge 11A is transmitted to the control unit 18. The second supply pressure gauge 11B is configured to measure the supply pressure of the second hydrogen production device 2B. The measured supply pressure value obtained by the second supply pressure gauge 11B is transmitted to the control unit 18.

[0021] The two tank supply lines 12A and 12B are hereinafter referred to as the first tank supply line 12A and the second tank supply line 12B. The first tank supply line 12A is configured to supply hydrogen from the corresponding first hydrogen production device 2A to the buffer tank 3. The first tank supply line 12A connects the first hydrogen production device 2A and the buffer tank 3. The second tank supply line 12B is configured to supply hydrogen from the corresponding second hydrogen production device 2B to the buffer tank 3. The second tank supply line 12B connects the second hydrogen production device 2B and the buffer tank 3. The first tank supply line 12A and the second tank supply line 12B may be individually connected to the buffer tank 3. In this case, the first tank supply line 12A and the second tank supply line 12B do not merge.

[0022] The two tank supply valves 13A and 13B are hereinafter referred to as the first tank supply valve 13A and the second tank supply valve 13B. The first tank supply valve 13A is configured to control the supply of hydrogen from the corresponding first hydrogen production device 2A to the buffer tank 3. The first tank supply valve 13A is provided in the first tank supply line 12A described above. The first tank supply valve 13A is configured to be switchable between an open state and a closed state, and can block the flow of hydrogen in the first tank supply line 12A. The second tank supply valve 13B is configured to control the supply of hydrogen from the corresponding second hydrogen production device 2B to the buffer tank 3. The second tank supply valve 13B is provided in the first tank supply line 12A described above. The second tank supply valve 13B is configured to be switchable between an open state and a closed state, and can block the flow of hydrogen in the second tank supply line 12B.

[0023] The internal pressure gauge 14 is configured to measure the internal pressure of the buffer tank 3. The measured value of the internal pressure measured by the internal pressure gauge 14 is transmitted to the control unit 18.

[0024] The compressor supply line 15 is configured to supply hydrogen from the buffer tank 3 to the compressor 4. The compressor supply line 15 connects the buffer tank 3 and the compressor 4.

[0025] The compressor supply valve 16 is configured to control the supply of hydrogen from the buffer tank 3 to the compressor 4. The compressor supply valve 16 is located in the compressor supply line 15 described above. The compressor supply valve 16 is configured to be switchable between an open state and a closed state, and is capable of shutting off the flow of hydrogen in the compressor supply line 15.

[0026] The pressure relief valve 17 is configured to control the release of hydrogen from the buffer tank 3 to the outside. The pressure relief valve 17 is configured to be switchable between an open state and a closed state, and is configured to open when the internal pressure of the buffer tank 3 reaches a third reference pressure. The third reference pressure may be higher than the second reference pressure described above.

[0027] The control unit 18 is configured to control the first tank supply valve 13A, the second tank supply valve 13B, the compressor supply valve 16, and the pressure relief valve 17 described above. The control unit 18 may also control the operation of the hydrogen production apparatus 2A, 2B and the compressor 4. The control unit 18 may consist of one control device, or it may consist of two or more control devices divided according to their functions.

[0028] The control unit 18 may control each tank supply valve 13A, 13B. The control unit 18 opens each tank supply valve 13A, 13B when the supply pressure measured by each supply pressure gauge 11A, 11B reaches a first reference pressure. More specifically, the control unit 18 opens both the first tank supply valve 13A and the second tank supply valve 13B when both the supply pressure measured by the first supply pressure gauge 11A and the supply pressure measured by the second supply pressure gauge 11B reach a first reference pressure. In other words, if at least one of the supply pressure measured by the first supply pressure gauge 11A and the supply pressure measured by the second supply pressure gauge 11B has not reached a first reference pressure, both the first tank supply valve 13A and the second tank supply valve 13B are closed.

[0029] The control unit 18 may control the compressor supply valve 16. The control unit 18 opens the compressor supply valve 16 when the internal pressure measured by the internal pressure gauge 14 reaches the second reference pressure. In other words, if the internal pressure measured by the internal pressure gauge 14 has not reached the second reference pressure, the compressor supply valve 16 is closed. The control unit 18 may start the compressor 4 at the same time as opening the compressor supply valve 16.

[0030] The control unit 18 may control the pressure relief valve 17. The control unit 18 opens the pressure relief valve 17 when the internal pressure measured by the internal pressure gauge 14 reaches the third reference pressure. In other words, the pressure relief valve 17 is closed when the internal pressure measured by the internal pressure gauge 14 has not reached the third reference pressure.

[0031] Next, we will describe the operation method of the hydrogen production and storage system 1 according to this embodiment, which has the configuration described above.

[0032] If the pressure of the hydrogen stored in the accumulator 5 decreases, the control unit 18 activates the first hydrogen production device 2A and the second hydrogen production device 2B. As a result, hydrogen is produced by each hydrogen production device 2A and 2B, and the supply pressure of each hydrogen production device 2A and 2B increases. The supply pressure of each hydrogen production device 2A and 2B is measured by the corresponding supply pressure gauges 11A and 11B, and the measured values ​​are transmitted to the control unit 18.

[0033] When both the supply pressure measured by the first supply pressure gauge 11A and the supply pressure measured by the second supply pressure gauge 11B reach the first reference pressure, the control unit 18 opens both the first tank supply valve 13A and the second tank supply valve 13B. As a result, hydrogen produced by the first hydrogen production device 2A is supplied to the buffer tank 3 through the first tank supply line 12A, and hydrogen produced by the second hydrogen production device 2B is supplied to the buffer tank 3 through the second tank supply line 12B. The first tank supply valve 13A and the second tank supply valve 13B may be opened simultaneously.

[0034] When hydrogen is supplied to the buffer tank 3, the internal pressure of the buffer tank 3 increases. The internal pressure is measured by the internal pressure gauge 14, and the measured value is transmitted to the control unit 18.

[0035] When the internal pressure measured by the internal pressure gauge 14 reaches the second reference pressure, the control unit 18 opens the compressor supply valve 16 and starts the compressor 4. As a result, hydrogen is supplied from the buffer tank 3 to the compressor 4 through the compressor supply line 15. The compressor 4 compresses the hydrogen to increase its pressure and discharges it to the accumulator 5. In this way, hydrogen is supplied to the compressor 4 only after the internal pressure of the buffer tank 3 reaches the second reference pressure. This suppresses fluctuations in the pressure of the hydrogen supplied to the compressor 4 and ensures uniformity of the hydrogen pressure supplied to the compressor 4. Therefore, a stable supply of hydrogen to the accumulator 5 becomes possible.

[0036] In this way, hydrogen is supplied to the accumulator 5, and the hydrogen pressure inside the accumulator 5 is increased. The operation of each hydrogen production device 2A and 2B continues until the hydrogen pressure inside the accumulator 5 reaches a predetermined pressure, and hydrogen is supplied from the buffer tank 3 to the accumulator 5.

[0037] While the hydrogen production and accumulating system 1 is in operation, the opening and closing of the tank supply valves 13A and 13B are controlled based on the supply pressure of each hydrogen production device 2A and 2B, and the opening and closing of the compressor supply valve 16 is controlled based on the internal pressure of the buffer tank 3. In this way, the hydrogen production and accumulating system 1 is operated while balancing the supply pressure of each hydrogen production device 2A and 2B with the internal pressure of the buffer tank 3.

[0038] As described above, according to this embodiment, when the supply pressure of the corresponding hydrogen production devices 2A and 2B, as measured by the respective supply pressure gauges 11A and 11B, reaches the first reference pressure, the respective tank supply valves 13A and 13B open. This prevents the respective tank supply valves 13A and 13B from opening if the supply pressure of at least one of the first hydrogen production device 2A and the second hydrogen production device 2B has not reached the first reference pressure. However, if the hydrogen production devices 2A and 2B, whose supply pressure is lower than the first reference pressure, are connected to the buffer tank 3, the supply of hydrogen to the buffer tank 3 may be hindered due to the low supply pressure. In this case, the hydrogen production efficiency of the hydrogen production devices 2A and 2B may decrease. In contrast, according to this embodiment, such a decrease in hydrogen production efficiency can be prevented. For example, even if there is a difference in the startup timing of the respective hydrogen production devices 2A and 2B, or a difference in the rate of increase of the supply pressure after startup, it is possible to prevent the respective tank supply valves 13A and 13B from opening if the supply pressure of at least one of the hydrogen production devices 2A and 2B is low. As a result, hydrogen production efficiency can be improved.

[0039] Furthermore, according to this embodiment, the respective tank supply lines 12A and 12B that supply hydrogen from the corresponding hydrogen production devices 2A and 2B to the buffer tank 3 are individually connected to the buffer tank 3. This prevents the supply of hydrogen from being hindered from the hydrogen production device with the lower supply pressure to the buffer tank 3, even when a pressure difference exists between the supply pressure of the first hydrogen production device 2A and the supply pressure of the second hydrogen production device 2B. Therefore, the hydrogen production efficiency can be improved.

[0040] Furthermore, according to this embodiment, the compressor supply valve 16 opens when the internal pressure of the buffer tank 3, as measured by the internal pressure gauge 14, reaches the second reference pressure. This prevents the compressor supply valve 16 from opening when the internal pressure of the buffer tank 3 has not reached the second reference pressure. If the buffer tank 3 is connected to the compressor 4 when the internal pressure is lower than the second reference pressure, the internal pressure of the buffer tank 3 may become unstable, potentially reducing the production efficiency of each hydrogen production device 2A and 2B. Also, if the internal pressure of the buffer tank 3 is unstable, the amount of hydrogen compressed by the compressor 4 may also become unstable.

[0041] Furthermore, according to this embodiment, when the internal pressure of the buffer tank 3 reaches the third reference pressure, the pressure relief valve 17 opens. This allows hydrogen in the buffer tank 3 to be released to the outside, thereby lowering the internal pressure of the buffer tank 3. As a result, it is possible to prevent the internal pressure of the buffer tank 3 from becoming higher than the supply pressure of the hydrogen production devices 2A and 2B, and to prevent a decrease in the hydrogen production efficiency of the hydrogen production devices 2A and 2B. It is also possible to prevent the hydrogen supply pressure to the compressor 4 from increasing.

[0042] (Second Embodiment) Next, the hydrogen production and storage system in the second embodiment will be described using Figure 2.

[0043] In the second embodiment shown in Figure 2, the main difference is that the supply of hydrogen from the buffer tank to the compressor is controlled by a pressure-holding valve; other configurations are substantially the same as those of the first embodiment shown in Figure 1. In Figure 2, the same reference numerals are used for parts identical to those in the first embodiment shown in Figure 1, and detailed descriptions are omitted.

[0044] As shown in Figure 2, the hydrogen production accumulator system 1 according to this embodiment is equipped with a pressure-holding valve 19. The pressure-holding valve 19 is configured to control the supply of hydrogen from the buffer tank 3 to the compressor 4. The pressure-holding valve 19 is located in the compressor supply line 15 described above. The pressure-holding valve 19 is configured to be switchable between an open state and a closed state, and is capable of shutting off the flow of hydrogen in the compressor supply line 15.

[0045] The pressure-holding valve 19 may be configured to open when the internal pressure of the buffer tank 3 reaches a fourth reference pressure. More specifically, the pressure-holding valve 19 may be configured such that an elastic body, such as a spring (not shown), supporting a valve body moves when the fourth reference pressure is reached, causing the pressure-holding valve 19 to open. In this case, the pressure-holding valve 19 can open at a predetermined pressure without being controlled by the control unit 18. Such a pressure-holding valve 19 may also be called a back pressure valve. The fourth reference pressure may be equal to the second reference pressure described above.

[0046] In the hydrogen production accumulator system 1 shown in Figure 2, the compressor supply line 15 does not have the compressor supply valve 16 shown in Figure 1. However, this embodiment is not limited to this, and the compressor supply line 15 may have both a pressure-holding valve 19 and a compressor supply valve 16.

[0047] As described above, according to this embodiment, the pressure-holding valve 19 opens when the internal pressure of the buffer tank 3 reaches the fourth reference pressure. This prevents the pressure-holding valve 19 from opening when the internal pressure of the buffer tank 3 has not reached the fourth reference pressure. If the buffer tank 3 is connected to the compressor 4 when the internal pressure is lower than the fourth reference pressure, the internal pressure of the buffer tank 3 may become unstable due to the stroke of the compressor 4, potentially reducing the production efficiency of each hydrogen production device 2A, 2B. In contrast, according to this embodiment, the internal pressure of the buffer tank 3 can be stabilized by the pressure-holding valve 19, preventing a decrease in hydrogen production efficiency. As a result, hydrogen production efficiency can be improved. That is, even if the supply of hydrogen by the tank supply valves 13A and 13B described above is not controlled, the presence of the pressure-holding valve 19 allows for the improvement of hydrogen production efficiency as described above. Furthermore, the pressure of the hydrogen supplied from the buffer tank 3 to the compressor 4 can be stabilized, and the amount of hydrogen compressed by the compressor 4 can be stabilized.

[0048] (Third embodiment) Next, the hydrogen production and storage system in the third embodiment will be described using Figure 3.

[0049] In the third embodiment shown in Figure 3, the main difference is that an internal pressure adjustment section made of a hydrogen storage alloy is provided inside the buffer tank; the other configurations are substantially the same as those of the first embodiment shown in Figure 1. In Figure 2, the same reference numerals are used for parts identical to those in the first embodiment shown in Figure 1, and detailed descriptions are omitted.

[0050] As shown in Figure 3, an internal pressure adjustment unit 20 is provided inside the buffer tank 3 according to this embodiment. The internal pressure adjustment unit 20 is configured to adjust the internal pressure of the buffer tank 3. The internal pressure adjustment unit 20 is made of a hydrogen storage alloy. When the hydrogen storage alloy is pressurized, it absorbs hydrogen. In this case, the internal pressure of the buffer tank 3 can be lowered. On the other hand, when the hydrogen storage alloy is depressurized, it releases the hydrogen it has absorbed. In this case, the internal pressure of the buffer tank 3 can be increased. Figure 3 shows an example in which a compressor supply valve 16 is provided in the compressor supply line 15, but instead of the compressor supply valve 16, a pressure-holding valve 19 as shown in Figure 2 may be provided.

[0051] As shown in Figure 3, the buffer tank 3 may be equipped with a temperature control device 21. The temperature control device 21 is configured to adjust the temperature of the internal pressure adjustment unit 20 inside the buffer tank 3. By increasing the temperature of the internal pressure adjustment unit 20, the amount of hydrogen absorbed by the hydrogen storage alloy can be reduced, and the absorbed hydrogen can be released. In this case, the internal pressure of the buffer tank 3 can be increased. On the other hand, by lowering the temperature of the internal pressure adjustment unit 20, the amount of hydrogen absorbed by the hydrogen storage alloy can be increased, and hydrogen can be absorbed inside the buffer tank 3. In this case, the internal pressure of the buffer tank 3 can be lowered.

[0052] As described above, according to this embodiment, an internal pressure adjustment unit 20 made of a hydrogen storage alloy is provided inside the buffer tank 3. As a result, when the internal pressure of the buffer tank 3 increases, hydrogen is absorbed into the internal pressure adjustment unit 20, and when the internal pressure decreases, hydrogen is released from the internal pressure adjustment unit 20. Therefore, the internal pressure of the buffer tank 3 can be adjusted, and fluctuations in the internal pressure of the buffer tank 3 can be suppressed. As a result, the pressure of the hydrogen supplied to the compressor 4 can be made uniform, and the hydrogen production efficiency of the hydrogen production devices 2A and 2B can be improved.

[0053] Furthermore, according to this embodiment, the temperature of the internal pressure adjustment unit 20 can be adjusted by the temperature control device 21. This allows for adjustment of the amount of hydrogen stored in the internal pressure adjustment unit 20. As a result, fluctuations in the internal pressure of the buffer tank 3 can be further suppressed.

[0054] According to the embodiments described above, hydrogen production efficiency can be improved.

[0055] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. Naturally, these embodiments can also be combined in part as appropriate within the scope of the spirit of the invention. [Explanation of symbols]

[0056] 1: Hydrogen production accumulator system, 2A: First hydrogen production device, 2B: Second hydrogen production device, 3: Buffer tank, 4: Compressor, 5: Accumulator, 11A: First supply pressure gauge, 11B: Second supply pressure gauge, 12A: First tank supply line, 12B: Second tank supply line, 13A: First tank supply valve, 13B: Second tank supply valve, 14: Internal pressure gauge, 15: Compressor supply line, 16: Compressor supply valve, 17: Pressure relief valve, 18: Control unit, 19: Pressure holding valve, 20: Internal pressure adjustment unit, 21: Temperature control device

Claims

1. Multiple hydrogen production devices, A buffer tank for storing hydrogen supplied from multiple hydrogen production devices, A compressor for compressing hydrogen supplied from the buffer tank, An accumulator for storing hydrogen compressed by the aforementioned compressor, Multiple supply pressure gauges for measuring the hydrogen supply pressure of each of the hydrogen production devices, A plurality of tank supply valves that control the supply of hydrogen from the corresponding hydrogen production apparatus to the buffer tank, Control unit and Equipped with, The control unit controls each of the tank supply valves to open each of the tank supply valves when the supply pressure measured by all of the supply pressure gauges reaches the first reference pressure. Hydrogen production and storage system.

2. A tank supply line for supplying hydrogen from a corresponding hydrogen production apparatus to a buffer tank, comprising a plurality of tank supply lines each provided with a corresponding tank supply valve, Each of the tank supply lines is individually connected to the buffer tank. The hydrogen production and storage system according to claim 1.

3. An internal pressure gauge for measuring the internal pressure of the buffer tank, A compressor supply valve that controls the supply of hydrogen from the buffer tank to the compressor, Equipped with, The control unit controls the compressor supply valve to open the compressor supply valve when the internal pressure measured by the internal pressure gauge reaches the second reference pressure. A hydrogen production and storage system according to claim 1 or 2.

4. The buffer tank is equipped with a pressure relief valve that opens when the internal pressure reaches a third reference pressure. A hydrogen production and storage system according to claim 1 or 2.

5. The system includes a pressure-holding valve that controls the supply of hydrogen from the buffer tank to the compressor, The pressure-holding valve opens when the internal pressure of the buffer tank reaches the fourth reference pressure. A hydrogen production and storage system according to claim 1 or 2.

6. Hydrogen production equipment, A buffer tank for storing hydrogen supplied from the hydrogen production apparatus, A compressor for compressing hydrogen supplied from the buffer tank, An accumulator for storing hydrogen compressed by the aforementioned compressor, A pressure-holding valve that controls the supply of hydrogen from the buffer tank to the compressor, Equipped with, The pressure-holding valve opens when the internal pressure of the buffer tank reaches the fourth reference pressure. Hydrogen production and storage system.

7. The buffer tank is provided with an internal pressure adjustment unit that adjusts the internal pressure of the buffer tank, The internal pressure adjustment section is made of a hydrogen storage alloy capable of absorbing and releasing hydrogen. A hydrogen production and storage system according to claim 1 or 6.

8. The system further includes a temperature control device capable of adjusting the temperature of the internal pressure adjustment section, The hydrogen production and storage system according to claim 7.

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