A hydrogen production and energy storage power generation system for high-temperature water vapor electrolysis and a working method thereof

Abstract

The application discloses a high-temperature water vapor electrolysis hydrogen production energy storage power generation system and a working method thereof. The application couples a heat pump energy storage system with hydrogen production and gas power generation, utilizes high-temperature heat storage of the heat pump and waste heat of the high-temperature waste heat water and the gas combined cycle generator set, realizes the combination of energy storage and thermal power and green power conversion industry, provides oxygen for a gas turbine while producing hydrogen, improves efficiency, and has good economic efficiency and application value.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a high-temperature water vapor electrolysis hydrogen production and energy storage power generation system and its working method. Background Technology

[0002] Compared with room-temperature water electrolysis for hydrogen production, high-temperature (600–1000°C) steam electrolysis based on solid oxide electrolysis cells (SOECs) has significant advantages: energy consumption during electrolysis is reduced by 20%–30% at high temperatures, and electrolysis efficiency can reach 90%–100%. However, the electrolysis process consumes a large amount of electrical and thermal energy.

[0003] Heat pump energy storage systems utilize a heat pump cycle to convert electrical energy into heat and cold energy during charging, storing these energies separately using a high-temperature heat transfer medium and a low-temperature refrigerant medium. During discharging, a heat engine cycle converts the stored heat and cold energy back into electrical energy. Heat pump energy storage systems include a high-temperature thermal storage system with temperatures exceeding 500℃, theoretically reaching a maximum of 900℃. They also contain high-temperature waste water. As a highly efficient and low-cost energy storage system, heat pump energy storage systems can be used for heating and green energy conversion.

[0004] Gas-steam combined cycle power generation is a common thermal power generation method. Its waste heat temperature is about 500-600℃, which is a good heat source for vaporizing water. Summary of the Invention

[0005] The present invention aims to at least partially solve one of the technical problems in the related art.

[0006] Therefore, embodiments of the present invention propose a high-temperature water electrolysis steam hydrogen production and energy storage power generation system and its working method.

[0007] In a first aspect, the present invention proposes a high-temperature water vapor electrolysis hydrogen production and energy storage power generation system, comprising:

[0008] A solid oxide electrolysis water vapor hydrogen production system produces oxygen and hydrogen containing water vapor by electrolyzing high-temperature water vapor.

[0009] A heat pump energy storage system includes a thermal storage system, a cold storage system, and a cooler. The working process of the heat pump energy storage system is divided into a charging process and a discharging process.

[0010] A gas-steam combined cycle power generation system includes a turbine, a steam turbine, a combustion chamber, and a boiler. Oxygen generated from the electrolysis of high-temperature steam enters the combustion chamber for combustion. Part of the exhaust steam or extracted steam from the turbine is heated by part of the turbine's waste heat, and then further heated by a high-temperature working fluid in the thermal storage system or the heat pump energy storage system to become high-temperature steam for hydrogen production via electrolysis. During the charging process, condensate from part of the turbine's exhaust steam and hydrogen containing water vapor are condensed by the cooling system and used as feedwater in the boiler. During the discharging process, part of the condensate from the turbine's exhaust steam and hydrogen containing water vapor is heated by the cooling system and then used as feedwater in the boiler.

[0011] Furthermore, a portion of the waste heat from the turbine is introduced into the boiler to heat the feedwater.

[0012] Furthermore, the gas-steam combined cycle power generation system also includes a gas turbine compressor, where air enters the air compressor, is compressed, and then enters the combustion chamber for combustion, releasing heat and doing work.

[0013] Furthermore, the gas-steam combined cycle power generation system also includes a flue gas-steam heat exchanger and a high-temperature superheater located downstream of the flue gas-steam heat exchanger. Part of the exhaust steam or extraction steam from the turbine is heated by part of the waste heat from the turbine in the flue gas-steam heat exchanger and then enters the high-temperature superheater. In the high-temperature superheater, the exhaust steam or extraction steam is reheated by the high-temperature working fluid of the thermal storage system or the heat pump energy storage system to become high-temperature steam. The high-temperature steam is then used in the solid oxide electrolysis water vapor hydrogen production system.

[0014] Furthermore, the gas-steam combined cycle power generation system also includes a first condenser and a second condenser. Part of the exhaust steam from the turbine enters the first condenser and is condensed into condensate, while the hydrogen containing water vapor enters the second condenser and is condensed into condensate, thereby cooling and separating the hydrogen and steam.

[0015] Furthermore, the gas-steam combined cycle power generation system also includes a water supply device for supplying water to the boiler.

[0016] Furthermore, the thermal storage system includes a high-temperature heat exchanger, a high-temperature thermal storage tank, and a low-temperature thermal storage tank, with the high-temperature thermal storage tank and the low-temperature thermal storage tank respectively located at the inlet and outlet ends of the high-temperature heat exchanger; the cold storage system includes a low-temperature heat exchanger, a low-temperature cold storage tank, and a high-temperature cold storage tank, with the low-temperature cold storage tank and the high-temperature cold storage tank respectively located at the inlet and outlet ends of the low-temperature heat exchanger.

[0017] Furthermore, the heat pump energy storage system also includes an energy storage motor, a high-temperature compressor, a low-temperature expander, and a regenerator. During the charging process, the energy storage motor drives the high-temperature compressor to heat the circulating working fluid to a high-temperature and high-pressure state, and then the fluid flows sequentially through the high-temperature heat exchanger, the regenerator, and the low-temperature expander to cool down. Finally, the fluid flows sequentially through the low-temperature heat exchanger, the regenerator, the high-temperature heat exchanger, and the high-temperature compressor to heat up and complete the energy storage cycle.

[0018] Furthermore, the heat pump energy storage system also includes a starter motor, a cryogenic compressor, and a high-temperature expander. During the discharge process, the starter motor drives the cryogenic compressor to heat and pressurize the circulating working fluid to a medium-temperature and high-pressure state, and then flows through the regenerator and the high-temperature heat exchanger in sequence to be heated before entering the high-temperature expander to do work. After doing work, the working fluid flows through the regenerator, the cooler, and the cryogenic heat exchanger in sequence to be cooled before entering the cryogenic compressor to complete the discharge cycle.

[0019] Secondly, the present invention provides a method for operating the system proposed in the first aspect, comprising the following steps:

[0020] After being compressed by the gas turbine compressor, air enters the combustion chamber and burns, releasing heat and doing work to drive the turbine to rotate and generate electricity. Part of the waste heat generated by the turbine enters the boiler to heat the feedwater and generate high-temperature and high-pressure steam to drive the steam turbine to generate electricity. Part of the exhaust steam or extraction steam generated by the steam turbine enters the flue gas-steam heat exchanger and is heated by the waste heat of the turbine. Then it enters the high-temperature superheater and is reheated by the high-temperature working fluid or high-temperature heat storage medium of the heat pump energy storage system. After being heated, it enters the solid oxide electrolysis water vapor hydrogen production system, where it is electrolyzed to produce oxygen and hydrogen containing water vapor.

[0021] Hydrogen containing water vapor is separated into hydrogen and condensate in the second condenser by a low-temperature cold storage medium. Part of the exhaust steam or extracted steam from the steam turbine enters the first condenser and is condensed into condensate. During the charging process of the heat pump energy storage system, all the condensate is fed into the boiler as feedwater. During the discharge process of the heat pump energy storage system, part of the condensate enters the cooler and is heated before being fed into the boiler as feedwater.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] This invention couples a heat pump energy storage system with hydrogen production and gas-fired power generation. It utilizes the high-temperature heat storage of the heat pump and the high-temperature waste water and waste heat of the gas-fired combined cycle generator set, realizing the integration of energy storage with thermal power and green power conversion industries. While producing hydrogen, it provides oxygen to the gas turbine, improving efficiency and having good economic and application value.

[0024] This invention utilizes the cooling water in the heat pump energy storage system, the condensate in the gas-steam combined cycle power generation system, and the condensate and hydrophobic water from the hydrogen / steam mixture produced by the solid oxide electrolysis water vapor hydrogen production system to achieve water-working fluid coupling in the system, which is beneficial for use in various regions. Attached Figure Description

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0026] Figure 1 This is a schematic diagram of the high-temperature water electrolysis steam hydrogen production and energy storage power generation system of the present invention;

[0027] Figure 2 This is a schematic diagram of the charging process of the heat pump energy storage system in the high-temperature water electrolysis steam hydrogen production and energy storage power generation system of the present invention;

[0028] Figure 3 This is a schematic diagram of the discharge process of the heat pump energy storage system in the high-temperature water electrolysis steam hydrogen production and energy storage power generation system of the present invention.

[0029] Explanation of reference numerals in the attached figures:

[0030] 1. Starting motor; 2. Cryogenic compressor; 3. Cryogenic heat exchanger; 4. High-temperature cold storage tank; 5. Cryogenic cold storage tank; 6. Cooler; 7. Regenerator; 8. Cryogenic heat storage tank; 9. High-temperature heat storage tank; 10. High-temperature heat exchanger; 11. High-temperature expander; 12. First generator; 13. Second condenser; 14. Water supply device; 15. High-temperature superheater; 16. Gas turbine compressor; 17. Combustion chamber; 18. Turbine; 19. Boiler; 20. Flue gas-steam heat exchanger; 21. Steam turbine; 22. First condenser; 23. Condensate pump; 24. Drain pump; 25. Second generator; 26. Third generator; 27. Solid oxide electrolysis water steam hydrogen production system; 28. Cryogenic expander; 29. ​​High-temperature compressor; 30. Energy storage motor; 31. First valve; 32. Second valve; 33. Third valve. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] like Figures 1-3 As shown, the high-temperature electrolysis water vapor hydrogen production and energy storage power generation system of the present invention includes a solid oxide electrolysis water vapor hydrogen production system 27, a heat pump energy storage system, and a gas-steam combined cycle power generation system.

[0033] The heat pump energy storage system includes a heat storage system, a cold storage system, a cooler 6, an energy storage motor 30, a high-temperature compressor 29, a low-temperature expander 28, a regenerator 7, a starter motor 1, a low-temperature compressor 2, and a high-temperature expander 11. The cooler 6 is only used during the discharge process of the heat pump energy storage system.

[0034] The heat storage system includes a high-temperature heat exchanger 10, a high-temperature heat storage tank 9, and a low-temperature heat storage tank 8. The high-temperature heat storage tank 9 and the low-temperature heat storage tank 8 are respectively located at the inlet and outlet ends of the high-temperature heat exchanger 10. The high-temperature heat storage tank 9 stores a high-temperature heat storage medium, and the low-temperature heat storage tank 8 stores a low-temperature heat storage medium. The heat storage medium can be potassium nitrate, calcium nitrate, sodium nitrate, sodium nitrite, lithium nitrate, mineral oil, heat transfer oil, liquid molten salt, etc.

[0035] The cold storage system includes a low-temperature heat exchanger 3, a low-temperature cold storage tank 5, and a high-temperature cold storage tank 4. The low-temperature cold storage tank 5 and the high-temperature cold storage tank 4 are respectively located at the inlet and outlet ends of the low-temperature heat exchanger 3. The high-temperature cold storage tank 4 stores a high-temperature cold storage medium, and the low-temperature cold storage tank 5 stores a low-temperature cold storage medium. The cold storage medium can be methanol, ethanol, ethylene glycol, calcium chloride solution or a mixture thereof, or it can be a calcium chloride aqueous solution, or it can be a phase change material such as ice slurry.

[0036] During the charging process, the energy storage motor 30 drives the high-temperature compressor 29 to heat the circulating working fluid to a high-temperature and high-pressure state. After cooling through the high-temperature heat exchanger 10, the regenerator 7, and the low-temperature expander 28, the fluid then heats up through the low-temperature heat exchanger 3, the regenerator 7, the high-temperature heat exchanger 10, and the high-temperature compressor 29 to complete the energy storage cycle.

[0037] Specifically, the first valve 31 is located at the cold side inlet of the cooler 6, the second valve 32 is located at the hot side outlet of the cooler 6, and the third valve 33 is connected in parallel with the cooler 6. During the charging process, the first valve 31 and the second valve 32 are closed, and the third valve 33 is opened, bypassing the cooler 6, meaning the cooler 6 does not work. The energy storage process of the heat pump energy storage system is a reverse Brayton cycle, utilizing electrical energy to store thermal and cold energy. The energy storage motor 30 consumes electrical energy to drive the high-temperature compressor 29, compressing the gaseous circulating working fluid to a high-temperature and high-pressure state. The high-temperature and high-pressure gaseous circulating working fluid flows through the high-temperature heat exchanger 10, where it exchanges heat with the heat storage medium in the heat storage system, causing its temperature to drop. The heat storage medium absorbs the heat from the gaseous circulating working fluid and stores it in the heat storage system. After that, the gaseous circulating working fluid, now at a lower temperature, enters the regenerator 7 to release heat and then enters the low-temperature expander 28 to cool down and depressurize, becoming a low-temperature and low-pressure state. The low-temperature and low-pressure gaseous circulating working fluid enters the low-temperature heat exchanger 3 of the cold storage system to exchange heat with the cold storage medium, which releases heat and stores it in the cold storage system. The low-temperature and low-pressure circulating working fluid further enters the regenerator 7 to exchange heat with the gaseous circulating working fluid on the hot side, causing its temperature to rise. Finally, it enters the high-temperature compressor 29, completing the energy storage cycle.

[0038] During the discharge process, the starting motor 1 drives the cryogenic compressor 2 to heat and pressurize the circulating working fluid to a medium-temperature and high-pressure state. The working fluid then flows through the regenerator 7 and the high-temperature heat exchanger 10 in sequence to be heated before entering the high-temperature expander 11 to do work. After doing work, the working fluid flows through the regenerator 7, the cooler 6, and the cryogenic heat exchanger 3 in sequence to be cooled before entering the cryogenic compressor 2 to complete the discharge cycle.

[0039] Specifically, during the discharge process, the first valve 31 and the second valve 32 are opened, and the third valve 33 is closed. The cooler 6 is connected to the system. The discharge process is a forward Brayton cycle, using the thermal and cold energy stored during the energy storage process to generate electrical energy. The starting motor 1 consumes electrical energy to drive the cryogenic compressor 2 to do work. The gaseous circulating working fluid is heated and pressurized to a medium-temperature and high-pressure state. The gaseous circulating working fluid enters the regenerator 7 and exchanges heat with the hot-side working fluid, becoming a medium-high temperature and high-pressure state. The gaseous circulating working fluid in the medium-high temperature and high-pressure state enters the high-temperature heat exchanger 10 to absorb heat from the heat storage medium, becoming a high-temperature and high-pressure state. At this time, the temperature of the heat storage medium decreases and it is stored in the cryogenic heat storage tank 8. Subsequently, the high-temperature and high-pressure gaseous circulating working fluid enters the high-temperature expander 11 to do work, becoming a low-temperature and low-pressure state. At the same time, the high-temperature expander 11 drives the gaseous circulating working fluid to achieve the same temperature and pressure. The first generator 12, coaxially mounted, generates electricity; the low-temperature, low-pressure gaseous circulating working fluid then enters the regenerator 7 to release heat to the cold-side working fluid, raising its temperature; subsequently, the gaseous circulating working fluid enters the cooler 6 to heat the cooling water, which absorbs the heat from the gaseous circulating working fluid and raises its temperature, serving as feedwater for the boiler 19 to supply high-temperature waste water for gas-steam power generation; after that, the gaseous circulating working fluid enters the low-temperature heat exchanger 3 and exchanges heat with the low-temperature cold storage medium, further reducing its temperature before entering the low-temperature compressor 2, completing one discharge cycle.

[0040] The gas-steam combined cycle power generation system can provide electricity to the solid oxide electrolysis water vapor hydrogen production system 27 and the heat pump energy storage system. The charging process of the heat pump energy storage system stores electrical energy, and the discharging process of the heat pump energy storage system can provide electricity to the solid oxide electrolysis water vapor hydrogen production system 27 and the gas-steam combined cycle power generation system. The energy source for the energy storage motor 30, the starter motor 1 in the heat pump energy storage system, and the electrolysis process of the solid oxide electrolysis water vapor hydrogen production system 27 can be the electricity generated by the gas-steam combined cycle power generation system, or the electricity generated by curtailed wind and solar power, thus playing a role in peak shaving for gas-fired power plants and improving the utilization rate of new energy sources.

[0041] The gas-steam combined cycle power generation system includes a turbine 18, a steam turbine 21, a boiler 19, a gas turbine compressor 16, a combustion chamber 17, a flue gas-steam heat exchanger 20, a high-temperature superheater 15, a first condenser 22, a second condenser 13, and a water makeup device 14. The gas turbine compressor 16, combustion chamber 17, turbine 18, boiler 19, and steam turbine 21 are arranged upstream and downstream in sequence. The high-temperature superheater 15 is located downstream of the flue gas-steam heat exchanger 20. Both the flue gas-steam heat exchanger 20 and the first condenser 22 are located at the outlet end of the steam turbine 21.

[0042] In the operation of the gas-steam combined cycle power generation system, the gas turbine compressor 16 and the second generator 25 are coaxially arranged. Air enters the gas turbine compressor 16, is compressed, and its temperature and pressure increase. It then enters the combustion chamber 17, where it burns and releases heat to do work. The high-temperature flue gas generated by combustion enters the turbine 18, driving the turbine 18 to rotate and generate electricity. Part of the high-temperature waste heat generated by the turbine 18 enters the flue gas-steam heat exchanger 20 to heat part of the exhaust steam or extraction steam generated by the turbine 21, and part enters the boiler 19 to heat the feedwater. The resulting high-temperature, high-pressure steam drives the third generator 26, which is coaxially arranged with the turbine 21, to generate electricity. In some embodiments, part of the exhaust steam generated by the turbine 21 enters the flue gas-steam heat exchanger 20 and is heated by the high-temperature waste heat generated by the turbine 18. Part of it enters the first condenser 22 and is condensed into condensate. During the charging process of the heat pump energy storage system, this condensate is fed into the boiler 19 as feedwater by the condensate pump 23. During the discharging process of the heat pump energy storage system, part of this condensate acts as a cold source, enters the cooler 6, is heated, and then enters the boiler 19 as feedwater. The water replenishment device 14 is used to replenish water to the boiler 19.

[0043] The exhaust steam or extraction steam, heated in the flue gas-steam heat exchanger 20, enters the high-temperature heat exchanger 10, where it is reheated to a specified temperature of high-temperature steam. This high-temperature steam then enters the solid oxide electrolysis water vapor hydrogen production system 27 for electrolysis. In some embodiments, the heat source for the high-temperature heat exchanger 10 is the heat storage medium in the high-temperature heat storage tank 9, such as... Figure 3 As shown. In some embodiments, the heat source for the high-temperature heat exchanger 10 is the outlet circulating working fluid (not shown) of the high-temperature compressor 29 in the heat pump energy storage system.

[0044] High-temperature steam enters the solid oxide electrolysis water vapor hydrogen production system 27 and is electrolyzed into oxygen and hydrogen containing water vapor. The oxygen enters the combustion chamber 17 to aid combustion and improve combustion efficiency, while the hydrogen containing water vapor enters the second condenser 13 to exchange heat with the low-temperature cold storage medium. The water vapor is condensed into condensate and separated from the hydrogen, producing pure hydrogen. During the charging process of the heat pump energy storage system, this condensate is fed into the boiler 19 as feedwater by the condensate pump 24. During the discharging process of the heat pump energy storage system, a portion of this condensate is heated in the cooler 6 as a cold source and then fed into the boiler 19.

[0045] In this invention, the heat pump energy storage system can deeply shaving peak loads during periods of low electricity prices. During discharge, in addition to supplying electricity to the grid, it can also provide electricity and heat to the hydrogen production cell via water electrolysis, and provide cooling for the generated hydrogen / steam mixture. Coupled with a gas-steam combined cycle, it not only improves the power plant's peak-shaving capacity but also produces green hydrogen, thus enhancing economic efficiency.

[0046] This invention utilizes a heat pump energy storage system to utilize the high-temperature waste hot water, high-temperature thermal energy, and low-temperature cold energy generated by the system during the discharge process. This energy is coupled with a solid oxide electrolysis water vapor hydrogen production system 27 and a gas-steam combined cycle power generation system to produce green hydrogen fuel products. This not only improves the economic efficiency of the system but also enhances the peak-shaving capacity of the gas-fired power plant.

[0047] The operating method of a high-temperature water electrolysis steam hydrogen production and storage power generation system includes the following steps:

[0048] Air is compressed by gas turbine compressor 16 and enters combustion chamber 17 for combustion, releasing heat and doing work, which drives turbine 18 to rotate and generate electricity. Part of the waste heat generated by turbine 18 enters boiler 19 to heat feedwater and generate high-temperature and high-pressure steam to drive steam turbine 21 to generate electricity. Part of the exhaust steam or extraction steam generated by steam turbine 21 enters flue gas-steam heat exchanger 20 and is heated by waste heat from turbine 18. Then it enters high-temperature superheater 15 and is reheated by high-temperature working fluid or high-temperature heat storage medium of heat pump energy storage system. After being heated, it enters solid oxide electrolysis water vapor to produce hydrogen system 27, where it is electrolyzed to produce oxygen and hydrogen containing water vapor.

[0049] Hydrogen containing water vapor is cooled and separated into hydrogen and condensate in the second condenser 13 by a low-temperature cold storage medium. Part of the exhaust steam from the turbine 21 enters the first condenser 22 and is condensed into condensate. During the charging process of the heat pump energy storage system, all the condensate is fed into the boiler 19 as feedwater. During the discharging process of the heat pump energy storage system, part of the condensate enters the cooler 6 and is heated before being fed into the boiler 19 as feedwater. The specific process will not be described further.

[0050] Due to the intermittency and instability of renewable energy sources such as solar and wind power, heat pump energy storage systems can provide a solution to the unstable output of renewable energy. Based on this, the discharge process of the heat pump energy storage system can be rapidly started, enabling the system to respond quickly to the power grid. Furthermore, since heat pump energy storage systems are not limited by geographical or geological conditions, they can flexibly provide stable output from solar, wind, or biomass energy sources. This invention couples the heat pump energy storage system with a gas-steam combined cycle power generation system and a solid oxide electrolysis water vapor hydrogen production system 27, achieving the functions of power generation, energy storage and peak shaving, and absorption of wind and solar power curtailment, as well as the production of green hydrogen from renewable energy. It also achieves the coupling of the water working medium within the system, making it suitable for various regions.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms may refer to different embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0053] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high-temperature water electrolysis steam hydrogen production and energy storage power generation system, characterized in that, include: A solid oxide electrolysis water vapor hydrogen production system produces oxygen and hydrogen containing water vapor by electrolyzing high-temperature water vapor. A heat pump energy storage system includes a thermal storage system, a cold storage system, and a cooler. The working process of the heat pump energy storage system is divided into a charging process and a discharging process. A gas-steam combined cycle power generation system includes a turbine, a steam turbine, a combustion chamber, and a boiler. Oxygen generated from the electrolysis of high-temperature steam enters the combustion chamber for combustion. Part of the exhaust steam or extracted steam from the steam turbine is heated by part of the waste heat from the turbine, and then further heated by the high-temperature working fluid in the thermal storage system or the heat pump energy storage system to become high-temperature steam for hydrogen production through electrolysis. During the charging process, condensate from part of the exhaust steam from the steam turbine and hydrogen containing water vapor are condensed by the cooling system and used as feedwater in the boiler. During the discharging process, part of the condensate from the exhaust steam from the steam turbine and hydrogen containing water vapor are condensed by the cooling system and then heated by the cooler before being used as feedwater in the boiler.

2. The system as described in claim 1, characterized in that, Part of the waste heat from the turbine is fed into the boiler to heat the feedwater.

3. The system as described in claim 1, characterized in that, The gas-steam combined cycle power generation system also includes a gas turbine compressor. Air enters the air compressor, is compressed, and then enters the combustion chamber for combustion, releasing heat and doing work.

4. The system as described in claim 1, characterized in that, The gas-steam combined cycle power generation system also includes a flue gas-steam heat exchanger and a high-temperature superheater located downstream of the flue gas-steam heat exchanger. Part of the exhaust steam or extraction steam from the turbine is heated by part of the waste heat from the turbine in the flue gas-steam heat exchanger and then enters the high-temperature superheater. In the high-temperature superheater, the exhaust steam or extraction steam is reheated by the high-temperature working fluid of the thermal storage system or the heat pump energy storage system to become high-temperature steam. The high-temperature steam is then used in the solid oxide electrolysis water vapor hydrogen production system.

5. The system as described in claim 1, characterized in that, The gas-steam combined cycle power generation system also includes a first condenser and a second condenser. Part of the exhaust steam from the turbine enters the first condenser and is condensed into condensate. The hydrogen containing water vapor enters the second condenser and is condensed into condensate, thereby cooling and separating the hydrogen and steam.

6. The system as described in claim 1, characterized in that, The gas-steam combined cycle power generation system also includes a water supply device for supplying water to the boiler.

7. The system as described in claim 1, characterized in that, The thermal storage system includes a high-temperature heat exchanger, a high-temperature thermal storage tank, and a low-temperature thermal storage tank, with the high-temperature thermal storage tank and the low-temperature thermal storage tank respectively located at the inlet and outlet ends of the high-temperature heat exchanger; the cold storage system includes a low-temperature heat exchanger, a low-temperature cold storage tank, and a high-temperature cold storage tank, with the low-temperature cold storage tank and the high-temperature cold storage tank respectively located at the inlet and outlet ends of the low-temperature heat exchanger.

8. The system as described in claim 1, characterized in that, The heat pump energy storage system also includes an energy storage motor, a high-temperature compressor, a low-temperature expander, and a regenerator. During the charging process, the energy storage motor drives the high-temperature compressor to heat the circulating working fluid to a high-temperature and high-pressure state. The fluid then flows sequentially through the high-temperature heat exchanger, the regenerator, and the low-temperature expander to cool down. Finally, it flows sequentially through the low-temperature heat exchanger, the regenerator, the high-temperature heat exchanger, and the high-temperature compressor to heat up and complete the energy storage cycle.

9. The system as described in claim 8, characterized in that, The heat pump energy storage system also includes a starter motor, a cryogenic compressor, and a high-temperature expander. During the discharge process, the starter motor drives the cryogenic compressor to heat and pressurize the circulating working fluid to a medium-temperature and high-pressure state. The working fluid then flows sequentially through the regenerator and the high-temperature heat exchanger to be heated before entering the high-temperature expander to perform work. After performing work, the working fluid flows sequentially through the regenerator, the cooler, and the cryogenic heat exchanger to be cooled before entering the cryogenic compressor to complete the discharge cycle.

10. A method for operating a high-temperature water electrolysis steam hydrogen production and energy storage power generation system, characterized in that, The system according to any one of claims 1 to 9 comprises the following steps: After being compressed by the gas turbine compressor, air enters the combustion chamber and burns, releasing heat and doing work to drive the turbine to rotate and generate electricity. Part of the waste heat generated by the turbine enters the boiler to heat the feedwater and generate high-temperature and high-pressure steam to drive the steam turbine to generate electricity. Part of the exhaust steam or extraction steam generated by the steam turbine enters the flue gas-steam heat exchanger and is heated by the waste heat of the turbine. Then it enters the high-temperature superheater and is reheated by the high-temperature working fluid or high-temperature heat storage medium of the heat pump energy storage system. After being heated, it enters the solid oxide electrolysis water vapor hydrogen production system, where it is electrolyzed to produce oxygen and hydrogen containing water vapor. Hydrogen containing water vapor is separated into hydrogen and condensate in the second condenser by a low-temperature cold storage medium. Part of the exhaust steam from the turbine enters the first condenser and is condensed into condensate. During the charging process of the heat pump energy storage system, all the condensate is fed into the boiler as feedwater. During the discharge process of the heat pump energy storage system, part of the condensate enters the cooler and is heated before being fed into the boiler as feedwater.

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