Pumped storage power generation system, pumped storage power generation method, hydrogen production system and hydrogen production method

Abstract

To provide a novel pumped storage power generation system, and also provide a novel hydrogen production system.SOLUTION: A pumped storage power generation system comprises a pumping unit that pumps water, a water storage unit that stores the water pumped by the pumping unit, and a pumped storage power generation unit that generates power by a downstream flow of water discharged from the water storage unit. A hydrogen production system comprises a hydrogen production unit that produces hydrogen by electrolyzing water, using power generated by the pumped storage power generation system.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a pumped-storage power generation system, a pumped-storage power generation method, a hydrogen production system, and a hydrogen production method.

Background Art

[0002] There is known a pumped-storage power generation system that pumps up water and generates electricity by dropping the water. In the pumped-storage power generation system, mainly at night when power consumption is low, surplus power is used to pump up water, and during the day when power consumption is high, electricity is generated by dropping the water.

[0003] In recent years, efforts to achieve a "decarbonized society" have been demanded, and hydrogen has attracted attention as an environmentally friendly fuel. It is also important to obtain the electricity required for hydrogen production without burdening the environment and in a reasonable manner.

Summary of the Invention

Problems to be Solved by the Invention

[0004] At least one object of the present invention is to provide a novel pumped-storage power generation system.

[0005] Another at least one object of the present invention is to provide a novel hydrogen production system.

Means for Solving the Problems

[0006] According to the present invention, the above object is [1] A pumped-storage power generation system including a pumping unit that pumps water, a water storage unit that stores the water pumped by the pumping unit, and a pumped-storage power generation unit that generates electricity by the flow of the water discharged from the water storage unit; [2] The pumped-storage power generation system according to [1], wherein the water storage unit has a water storage capacity of 3.3 times or more the amount of water required for the pumped-storage power generation unit to generate electricity continuously. [3] The water pumping unit uses the electric power generated by a wind power generation system installed at sea to pump seawater from the sea, and is the pumped-storage power generation system according to [1] or [2]; [4] The pumped-storage power generation system according to any one of [1] to [3], comprising a power storage unit that stores the electric power generated by the wind power generation system, and the water pumping unit is supplied with electric power from the power storage unit; [5] A pumped-storage power generation method comprising a water pumping step of pumping water, a water storage step of storing the water pumped in the water pumping step, and a pumped-storage power generation step of discharging and flowing down the water stored in the water storage step to generate electric power; [6] A hydrogen production system comprising a hydrogen production unit that electrolyzes water to produce hydrogen using the electric power generated by the pumped-storage power generation system according to any one of [1] to [4]; [7] A hydrogen production method comprising a hydrogen production step of electrolyzing water to produce hydrogen using the electric power generated by the pumped-storage power generation step according to [5]; It can be achieved by.

Advantages of the Invention

[0007] According to the present invention, a novel pumped-storage power generation system can be provided.

[0008] Also, according to the present invention, a novel hydrogen production system can be provided.

Brief Description of the Drawings

[0009]

Figure 1

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. However, the present invention is not limited to the following embodiments unless it contradicts the gist of the present invention.

[0011] (Hydrogen Generation System) A pumping power generation system, a wind power generation system, and a hydrogen production system are collectively referred to as a "system". FIG. 1 is a schematic diagram of the system according to an embodiment of the present invention. As shown in FIG. 1, the system of the present invention may be composed of a pumping power generation system 1, a wind power generation system 2, and a hydrogen production system 3.

[0012] The pumping power generation system 1 shown in FIG. 1 includes a power storage unit and / or a control unit 11, a pumping unit 12, a water storage unit 13, and a pumping power generation unit 14. The pumping power generation system 1 may have any configuration for pumping power generation other than the illustrated configuration. The wind power generation system 2 shown in FIG. 1 includes a wind power generation unit 21. Further, the hydrogen production system 3 shown in FIG. 1 includes a hydrogen production unit 31. In FIG. 1, solid arrows represent the flow of water, and broken arrows represent the flow of electricity. The pumping power generation system 1 shown in FIG. 1 performs pumping power generation using the electric power generated by the wind power generation system 2. Also, the hydrogen production system 3 shown in FIG. 1 produces hydrogen using the electric power generated by the pumping power generation system 1.

[0013] The pumping unit 12 included in the pumping power generation system 1 is for lifting water. In FIG. 1, the pumping unit 12 is lifting seawater from the sea to the water storage unit 13. A pumping pipe for passing water may be provided between a water intake source such as the sea and the water storage unit 13. A plurality of pumping pipes and / or pumping units 12 may be provided. The pumping unit 12 can be provided in the middle of the pumping pipe.

[0014] The pumping unit 12 may include a pump. The type of the pump is not particularly limited and can be designed as appropriate. The pump may be, for example, a non-positive displacement pump or a positive displacement pump. The pumping unit 12 may pump water by operating the pump with the electric power generated by the wind power generation system 2.

[0015] The wind power generation system 2 generates electricity by utilizing wind power. The power generation is performed by a wind power generation unit 21 provided in the wind power generation system 2. The wind power generation unit 21 may include a generator. The wind power generation system 2 may include any components for wind power generation, such as a windmill, a tower, and a control unit, in addition to the wind power generation unit 21. The control unit may include a power semiconductor including SiC (silicon carbide), GaN (gallium nitride), etc. The wind power generation system 2 converts the kinetic energy of the wind into rotational energy by the propeller of the windmill and generates electricity by rotating the generator.

[0016] In FIG. 1, the wind power generation system 2 is installed at sea. By installing the wind power generation system 2 at sea, stronger and more stable wind can be received compared to the case of installing it on land. Also, since the wind power generation system 2 is away from the living area, problems related to noise and landscape are less likely to occur. Furthermore, when the pumping unit 12 pumps seawater from the sea, the distance between the pumping unit 12 and the wind power generation system 2 can be easily reduced, so it becomes easy to supply the electric power generated by the wind power generation system 2 to the pumping unit 12. The method of installing the wind power generation system 2 at sea is not particularly limited and can be designed as appropriate. The method of installing the wind power generation system 2 at sea may be, for example, a fixed-bottom type or a floating type.

[0017] The number of the wind power generation unit 21, the windmill, and / or the tower provided in the wind power generation system 2 is not particularly limited and can be designed as appropriate. The number of the wind power generation unit 21, the windmill, and / or the tower can be determined according to the required installed capacity (equipment output) of the wind power generation system 2. That is, the number of the wind power generation unit 21, the windmill, and / or the tower may be determined so that the wind power generation system 2 can obtain a predetermined installed capacity (equipment output). It is preferable that the pumping unit 12 can perform pumping by the electric power generated by the wind power generation system 2.

[0018] The electric power generated by the wind power generation system 2 may be stored in the power storage unit 11 before being supplied to the water pumping unit 12. The power storage unit 11 may include a secondary battery such as a lithium-ion battery or a sodium-sulfur battery. By storing the electric power generated by the wind power generation system 2 in the power storage unit 11, it is possible to supply the electric power stored in the power storage unit 11 to the water pumping unit 12 even when the wind power generation system 2 cannot generate electricity. Also, when the water storage unit 13 is full and there is no need to supply power to the water pumping unit 12, it is possible to store the electric power generated by the wind power generation system 2 in the power storage unit 11.

[0019] Whether to store the electric power generated by the wind power generation system 2 in the power storage unit 11 or supply it directly to the water pumping unit 12 without passing through the power storage unit 11 can be switched, for example, by the control unit 11. The control unit 11 may perform the switching based on, for example, the water storage volume of the water storage unit 13, the power storage volume of the power storage unit 11, the power generation amount of the wind power generation unit 21, etc. Information about the power generation amount of the wind power generation unit 21 may be transmitted from the wind power generation system 2 to the pumped-storage power generation system 1.

[0020] The control unit 11 may perform control to stably supply the electric power generated by the wind power generation system 2 to the water pumping unit 12. The control unit 11 may include a power semiconductor containing SiC (silicon carbide), GaN (gallium nitride), etc. Although not shown, the pumped-storage power generation system 1 may include, in addition to the control unit 11, a control unit for performing information processing related to pumped-storage power generation in the pumped-storage power generation system 1.

[0021] In FIG. 1, the power storage unit and / or the control unit 11 is included in the pumped-storage power generation system 1, but the power storage unit and / or the control unit 11 may be included in the wind power generation system 2. By providing the system with the power storage unit and / or the control unit 11, it is possible to stably supply power to the water pumping unit 12 even when unstable power is generated by the wind power generation system 2.

[0022] In addition, when the system of the present invention does not include the power storage unit 11, the power generated by the wind power generation system 2 may be supplied to the water pumping unit 12 without passing through the power storage unit 11.

[0023] The water pumped by the water pumping unit 12 is stored in the water storage unit 13. The water storage unit 13 may be installed at a location with a high elevation. The greater the head when the water is dropped, the greater the power generation amount by pumped-storage power generation. The water storage unit 13 may be formed by using a natural water source such as a pond, a lake, or a river, or may be formed without using a natural water source. The water storage unit 13 may be a storage pool, a storage pond, or a storage dam.

[0024] Although not shown in the drawings, the water may be pumped step by step through one or more water storage units to the water storage unit 13 that discharges the water. By pumping the water step by step from the water intake source to the water storage unit 13, it becomes easy to pump the water to a high position without depending on the pump performance of the water pumping unit 12.

[0025] The water storage capacity of the water storage unit 13 is not particularly limited and can be designed as appropriate. The water storage capacity of the water storage unit 13 is preferably 3.3 times or more, more preferably 4 times or more, and even more preferably 5 times or more, in terms of volume ratio, of the amount of water required for the pumped-storage power generation unit 14 to generate power continuously. When the water storage capacity of the water storage unit 13 is 3.3 times or more of the amount of water required for the pumped-storage power generation unit 14 to generate power continuously, it becomes easy for the pumped-storage power generation unit 14 to generate power continuously. Here, the time of "generating power continuously" is not particularly limited and can be designed as appropriate. For example, it may be to generate power continuously for one day, for one week, or for one month.

[0026] The amount of water required for the pumped-storage power generation unit 14 to generate electricity continuously may be specified according to the amount of water per unit time required for the pumped-storage power generation unit 14 to generate electricity continuously. The amount of water per unit time required for the pumped-storage power generation unit 14 to generate electricity continuously may be the amount of water per unit time at which the waterwheel provided in the pumped-storage power generation unit 14 can obtain an optimal rotational speed, or may be the amount of water per unit time at which the waterwheel can obtain a predetermined rotational speed. It is preferable that the hydrogen production unit 31 can continuously produce hydrogen by the electric power generated when the waterwheel rotates at a predetermined rotational speed. The greater the amount of water flowing down per unit time, the higher the rotational speed of the waterwheel provided in the pumped-storage power generation unit 14, and the greater the power generation amount by the pumped-storage power generation. Note that the "rotational speed of the waterwheel" refers to the number of rotations of the waterwheel per unit time.

[0027] The pumped-storage power generation system 1 generates electricity by discharging and flowing down the water stored in the water storage unit 13. The pumped-storage power generation system 1 shown in FIG. 1 generates electricity by discharging seawater from the water storage unit 13 to the sea and flowing it down. A power generation pipe for passing water may be provided between the water storage unit 13 and the discharge destination such as the sea. A plurality of power generation pipes and / or pumped-storage power generation units 14 may be provided. The pumped-storage power generation unit 14 can be provided in the middle of the power generation pipe.

[0028] The amount of water discharged from the water storage section 13 per unit time is not particularly limited and can be designed as appropriate. The amount of water discharged from the water storage section 13 per unit time may be specified according to the amount of water per unit time required for the pumped-storage power generation section 14 to generate electricity continuously. The amount of water per unit time required for the pumped-storage power generation section 14 to generate electricity continuously may be the amount of water per unit time at which the waterwheel provided in the pumped-storage power generation section 14 can obtain an optimal rotation speed, or may be the amount of water per unit time at which the waterwheel can obtain a predetermined rotation speed. It is preferable that the hydrogen production section 31 can continuously produce hydrogen by the electric power generated when the waterwheel rotates at a predetermined rotation speed. The amount of water discharged from the water storage section 13 per unit time may be equal to the amount of water flowing down per unit time. The greater the amount of water flowing down per unit time, the higher the rotation speed per unit time of the waterwheel provided in the pumped-storage power generation section 14, and the greater the power generation amount by pumped-storage power generation. Note that the "rotation speed of the waterwheel" refers to the number of rotations of the waterwheel per unit time.

[0029] A valve or the like for adjusting the amount of water discharged from the water storage section 13 may be provided at the water discharge port located at the connection portion between the water storage section 13 and the power generation pipe. The adjustment of the amount of water discharged from the water storage section 13 may be performed by the control section provided in the pumped-storage power generation system 1. For example, the control section provided in the pumped-storage power generation system 1 may control the opening amount of the valve provided at the water discharge port based on the water storage amount of the water storage section 13, the power generation amount of the pumped-storage power generation section 14, the power consumption amount of the hydrogen production section 31, etc., to adjust the amount of water discharged from the water storage section 13. Information about the power consumption amount of the hydrogen production section 31 may be transmitted from the hydrogen production system 3 to the pumped-storage power generation system 1.

[0030] The pumping power generation unit 14 may be provided with a water turbine and a generator. The type of the water turbine is not particularly limited and can be designed as appropriate. The water turbine may be, for example, a Francis turbine, a Pelton turbine, a propeller turbine, or a cross-flow turbine. The type of the generator is not particularly limited and can be designed as appropriate. The water turbine may be directly connected to the generator. By rotating the water turbine by utilizing the force when water flows down, power can be generated by the generator directly connected to the water turbine. The power generated by the pumping power generation unit 14 is supplied to the hydrogen production unit 31 provided in the hydrogen production system 3.

[0031] The hydrogen production unit 31 electrolyzes water to produce hydrogen. The water to be electrolyzed may contain electrolytes such as sulfuric acid and sodium hydroxide. The hydrogen production unit 31 may be provided with a water tank, electrodes, and the like.

[0032] The hydrogen produced by the hydrogen production unit 31 can be stored in a hydrogen storage alloy tank, a high-pressure gas tank, a gas tank, or the like. Also, the oxygen generated simultaneously when water is electrolyzed can also be stored in a high-pressure gas tank, a gas tank, or the like. The hydrogen and oxygen produced by the electrolysis of water can be used for any purpose.

[0033] In addition to the hydrogen production unit 31, the hydrogen production system 3 may be provided with any configuration for hydrogen production, such as a control unit. The power generated by the pumping power generation unit 14 may also be supplied to any configuration provided in the hydrogen production system 3, such as a control unit.

[0034] The pumping power generation system 1 of the present invention separately includes a pumping pipe and a power generation pipe, and since the pumping unit and the power generation unit are separate bodies, power generation can be performed even while pumping water. Thereby, it becomes possible to continuously generate power by pumping power generation. Also, it becomes possible to stably produce hydrogen by utilizing pumping power generation.

[0035] In the pumping power generation system 1 of the present invention, the amount of water that can be pumped per unit time is preferably greater than the amount of water that can be discharged per unit time. Note that the "amount of water that can be discharged per unit time" may be the same as the "amount of water that can flow down per unit time". Further, the "amount of water that can be pumped per unit time" may refer to the amount of water that can be pumped per unit time when there is sufficient power supplied to the pumping unit 12. Since the amount of water that can be pumped per unit time is greater than the amount of water that can be discharged per unit time, it becomes possible to continuously generate power by pumping power generation even when the power supplied to the pumping unit 12 is power that is difficult to stably generate, such as renewable energy.

[0036] The relationship between the amount of water that can be pumped per unit time and the amount of water that can be discharged per unit time is not particularly limited and can be designed as appropriate. The relationship between the amount of water that can be pumped per unit time and the amount of water that can be discharged per unit time may be determined by the power generation method of the power supplied to the pumping unit 12.

[0037] For example, when the power supplied to the pumping unit 12 is obtained by wind power generation, the amount of water that can be pumped per unit time is preferably 3.3 times or more, more preferably 4 times or more, and even more preferably 5 times or more, in terms of volume ratio, the amount of water that can be discharged per unit time. Since the equipment utilization rate of wind power generation is about 30%, it is considered that continuous power generation becomes possible when the amount of water that can be pumped per unit time is 3.3 times or more the amount of water that can be discharged per unit time.

[0038] Also, for example, when the power supplied to the pumping unit 12 is obtained by solar power generation, the amount of water that can be pumped per unit time is preferably 6.6 times or more, more preferably 8 times or more, and even more preferably 10 times or more, in terms of volume ratio, the amount of water that can be discharged per unit time. Since the equipment utilization rate of solar power generation is about 15%, it is considered that continuous power generation becomes possible when the amount of water that can be pumped per unit time is 6.6 times or more the amount of water that can be discharged per unit time.

[0039] The amount of water that can be pumped per unit time can be adjusted according to the number of the water pumping pipes and the water pumping section 12, the thickness of the water pumping pipes, the pump performance of the water pumping section 12, and the like. Also, the amount of water that can be discharged per unit time can be adjusted according to the number of the power generation pipes and the pumped-storage power generation section 14, the thickness of the water pumping pipes, the power generation performance of the pumped-storage power generation section 14, and the like.

[0040] In the above description, the mode in which the pumped-storage power generation system 1 pumps seawater from the sea has been described. However, the pumped-storage power generation system 1 may pump water from other water sources. The other water sources may be, for example, rivers, lakes, ponds, etc. Alternatively, the other water sources may be, for example, artificial water storage parts such as dams. Also, the wind power generation system 2 may be installed on land.

[0041] Also, in the above description, the mode in which the power supplied to the water pumping section 1 is the power generated by the wind power generation system 2 has been described. However, the power supplied to the water pumping section 1 may be the power generated by other power generation methods. The other power generation methods may be, for example, solar power generation, hydroelectric power generation, or biomass power generation. Also, at least a part of the power supplied to the water pumping section 1 may be supplemented by commercial power. Furthermore, at least a part of the power supplied to the hydrogen production section 31 may be supplemented by commercial power.

[0042] In this way, by providing a pumped-storage power generation system including a water pumping section for pumping water, a water storage section for storing the water pumped by the water pumping section, and a pumped-storage power generation section for generating power by the flow of the water discharged from the water storage section, a novel pumped-storage power generation system can be provided. The power generated by pumped-storage power generation has stable voltage and current. It can be said that it is reasonable to continuously obtain power by the pumped-storage power generation system.

[0043] Also, in this way, by having the water storage section with a water storage capacity of 3.3 times or more the amount of water required for the pumped-storage power generation section to continuously generate power, it becomes easy for the pumped-storage power generation system to continuously generate power throughout the day.

[0044] Also, in this way, since the pumping unit uses the electric power generated by the wind power generation system installed at sea to pump seawater from the sea, the cost of constructing the lower water storage unit for pumped-storage power generation can be reduced, and pumped-storage power generation can be performed using renewable energy.

[0045] Renewable energy such as wind power generation is likely to have unstable voltage and current. On the other hand, the electric power generated by pumped-storage power generation has stable voltage and current. That is to say, it can be said that it is reasonable to perform pumped-storage power generation using renewable energy and generate electric power by pumped-storage power generation.

[0046] Also, in this way, by providing a power storage unit that stores the electric power generated by the wind power generation system, and the pumping unit being supplied with electric power from the power storage unit, stable pumping can be achieved.

[0047] Also, in this way, by providing a hydrogen production system with a hydrogen production unit that uses the electric power generated by the pumped-storage power generation system to electrolyze water to produce hydrogen, a new hydrogen production system can be provided.

[0048] The electric power generated by pumped-storage power generation has stable voltage and current, and it can be said that it is suitable for stably producing hydrogen. Therefore, by producing hydrogen using the electric power generated by pumped-storage power generation, it becomes possible to produce hydrogen reasonably.

Explanation of Reference Numerals

[0049] 1 Pumped-storage power generation system 2 Wind power generation system 3 Hydrogen production system 11 Power storage unit and / or control unit 12 Pumping unit 13 Water storage unit 14 Pumped-storage power generation unit 21 Wind power generation unit 31 Hydrogen production unit

Claims

1. A water pumping section for pumping water, A water storage section for storing the water pumped by the water pumping section, A pumped-storage power generation section for generating electricity by the flow-down of the water discharged from the water storage section and A pumped-storage power generation system.

2. The water storage section has a water storage capacity of 3.3 times or more the amount of water necessary for the pumped-storage power generation section to generate electricity continuously, The pumped-storage power generation system according to Claim 1.

3. The water pumping section uses the electric power generated by a wind power generation system installed at sea to pump seawater from the sea, The pumped-storage power generation system according to Claim 1 or 2.

4. A power storage section for storing the electric power generated by the wind power generation system and The water pumping section is supplied with electric power from the power storage section, The pumped-storage power generation system according to Claim 1 or 2.

5. A water pumping step for pumping water, A water storage step for storing the water pumped by the water pumping step, A pumped-storage power generation step for generating electricity by discharging and flowing down the water stored in the water storage step and A pumped-storage power generation method.

6. A hydrogen production section for producing hydrogen by electrolyzing water using the electric power generated by the pumped-storage power generation system according to Claim 1 or 2 and A hydrogen production system.

7. A hydrogen production step for producing hydrogen by electrolyzing water using the electric power generated by the pumped-storage power generation step according to Claim 5 and A hydrogen production method.

Images