Heat pump electricity storage system based on regenerative and subcooling and operation method thereof

Abstract

The application provides a heat pump electricity storage system based on heat recovery and cold recovery and an operation method thereof, and comprises a heat pump circuit, a high-temperature heat storage module, a low-temperature cold storage module and a power generation module. The heat pump circuit comprises a first compressor, a second compressor, a heat pump heat recovery device, a first heat exchanger, a heat pump cold recovery device and a second heat exchanger. The first compressor, the cold side of the heat pump heat recovery device, the second compressor, the first heat exchanger, the hot side of the heat pump heat recovery device, a fourth heat exchanger, the hot side of the heat pump cold recovery device, a first expander, the second heat exchanger and the cold side of the heat pump cold recovery device are sequentially connected through pipelines to form a loop. The first heat exchanger is used for heat exchange with the high-temperature heat storage module, and the second heat exchanger is used for heat exchange with the low-temperature cold storage module. In the application, the heat pump heat recovery device and the heat pump cold recovery device can recover the waste heat and waste cold of the working medium and the heat storage / cold storage medium after heat exchange, respectively. Through the two-stage compression intermediate heating and heat recovery and cold recovery design, the pressure ratio and temperature ratio are reduced, the development difficulty of thermomechanical equipment is reduced, and the electric-thermal conversion performance of the heat pump is improved.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, specifically to a heat pump energy storage system based on heat recovery and cooling, and its operation method. Background Technology

[0002] In recent years, with the continuous growth of installed capacity and power generation of renewable energy sources such as solar and wind power, the phenomenon of wind and solar curtailment has become serious. Large-scale wind power, photovoltaic and solar thermal energy bases need greater flexibility to ensure that wind and solar power, which has volatility and uncertainty, can be reliably integrated into the power system. Therefore, it is essential to equip them with energy storage.

[0003] Current large-scale wind power, photovoltaic, and solar thermal energy bases are generally located in deserts and Gobi areas. Electrochemical energy storage, represented by lithium battery energy storage, is costly and has poor thermal safety. At the same time, its geographical location and harsh environment make maintenance difficult and its lifespan relatively short. In contrast, heat pump energy storage has received widespread attention in recent years due to its advantages such as not being limited by geographical conditions, large energy storage capacity, and long energy storage time.

[0004] Heat pump energy storage mainly includes three processes: the charging process converts off-peak electricity or surplus electricity (such as photovoltaic power) into high-temperature heat energy and low-temperature cold energy through the heat pump; the storage of high-temperature heat energy and low-temperature cold energy; and the discharging process converts high-temperature heat energy and low-temperature cold energy into electrical energy output through the heat engine, relieving the pressure on the power grid during peak electricity demand.

[0005] Current technologies face several challenges. First, simultaneously achieving high-temperature thermal storage and low-temperature cold storage requires heat pumps to generate a large temperature difference, leading to poor heat pump performance and placing high demands on the compressor. Second, the irreversibility of the cycle necessitates the use of additional heat exchangers to release a significant amount of heat into the environment to match the cycle with the thermal / cold storage temperature, resulting in waste. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a heat pump energy storage system based on heat recovery and cooling, and its operation method.

[0007] The heat pump energy storage system based on heat recovery and cooling provided by the present invention includes a heat pump circuit, a high-temperature heat storage module, a low-temperature cold storage module, and a power generation module. The high-temperature heat storage module and the low-temperature cold storage module are both heat exchanged with the heat pump circuit, and the power generation module is heat exchanged with the high-temperature heat storage module.

[0008] Both the heat pump circuit and the power generation module are connected to the external power grid. The power generation module is used to supply power to the external power grid. The heat pump circuit is driven by the power to be consumed and is used to absorb heat from the low-temperature cold storage module and release heat to the high-temperature heat storage module. The low-temperature cold storage module is used to store low-temperature cold energy, and the high-temperature heat storage module is used to store high-temperature heat energy.

[0009] The heat pump circuit includes a first compressor, a second compressor, a heat pump regenerator, a first heat exchanger, a fourth heat exchanger, a heat pump cooler, a first expander, and a second heat exchanger.

[0010] The first compressor, the cold side of the heat pump regenerator, the second compressor, the first heat exchanger, the hot side of the heat pump regenerator, the fourth heat exchanger, the hot side of the heat pump cooler, the first expander, the second heat exchanger, and the cold side of the heat pump cooler are connected in sequence through pipelines to form a loop.

[0011] The first heat exchanger is used for heat exchange with the high-temperature thermal storage module, and the second heat exchanger is used for heat exchange with the low-temperature cold storage module.

[0012] Preferably, the heat pump circuit further includes an external heating device;

[0013] The cold-side inlet of the heat pump regenerator is connected to the outlet of the first compressor, and the cold-side outlet of the heat pump regenerator is connected to the inlet of the external heating device. The hot-side inlet of the heat pump regenerator is connected to the outlet of the heat pump working fluid of the first heat exchanger.

[0014] The heat pump regenerator's hot-side outlet is connected to the fourth heat exchanger, which is used to output waste heat for heating. The heat pump cooler's hot-side inlet is connected to the fourth heat exchanger.

[0015] The hot-side outlet of the heat pump cooler is connected to the inlet of the first expander, the outlet of the first expander is connected to the inlet of the heat pump working fluid of the second heat exchanger, the cold-side inlet of the heat pump cooler is connected to the outlet of the heat pump working fluid of the second heat exchanger, and the cold-side outlet of the heat pump cooler is connected to the inlet of the first compressor.

[0016] Both the first compressor and the second compressor are connected to an external power grid and are driven by the power required to be consumed.

[0017] Preferably, the high-temperature thermal storage module includes a high-temperature thermal storage tank, a third heat exchanger, a low-temperature thermal storage tank, and a first heat exchanger, which are connected in sequence through pipelines to form a loop.

[0018] The inlet of the first heat exchanger is connected to a low-temperature heat storage tank, the outlet of the first heat exchanger is connected to a high-temperature heat storage tank, the inlet of the third heat exchanger is connected to the high-temperature heat storage tank, and the outlet of the third heat exchanger is connected to the low-temperature heat storage tank.

[0019] The first heat exchanger serves as a shared component between the high-temperature thermal storage module and the heat pump circuit, and is used for heat exchange between the high-temperature thermal storage module and the heat pump circuit. The third heat exchanger serves as a shared component between the high-temperature thermal storage module and the power generation module, and is used for heat exchange between the high-temperature thermal storage module and the power generation module.

[0020] Preferably, the heat storage medium of the high-temperature heat storage module is molten salt.

[0021] Preferably, the low-temperature cold storage module includes a gas storage tank, a second heat exchanger, and a liquid storage tank, which are connected in sequence by pipelines.

[0022] The second heat exchanger serves as a shared component between the low-temperature cold storage module and the heat pump circuit, and is used for heat exchange between the low-temperature cold storage module and the heat pump circuit.

[0023] Preferably, the working fluid of the heat pump circuit is one of air, argon, nitrogen, helium, carbon dioxide, etc., and the cold storage medium of the low-temperature cold storage module is one or more of methanol, ethanol, propane, pentane, hydrogen, ammonia, nitrogen, oxygen, natural gas, etc.

[0024] Preferably, the power generation module includes a third heat exchanger, a second expander, a heat engine regenerator, a fifth heat exchanger, and a third compressor connected in sequence via pipelines, wherein the fifth heat exchanger is used to output waste heat for heating;

[0025] The outlet of the third heat exchanger for power generation is connected to the inlet of the second expander, the hot-side inlet of the heat engine regenerator is connected to the outlet of the second expander, the hot-side outlet of the heat engine regenerator is connected to the fifth heat exchanger, the cold-side inlet of the heat engine regenerator is connected to the outlet of the third compressor, and the cold-side outlet of the heat engine regenerator is connected to the inlet of the third heat exchanger for power generation.

[0026] The second expander is connected to a power generation device and is used to drive the power generation device to generate electricity. The power generation device is connected to an external power grid.

[0027] Preferably, the working fluid of the power generation module is one or more of the following, including but not limited to carbon dioxide, water vapor, air, and argon.

[0028] The operation method of the heat pump energy storage system based on heat recovery and cooling provided by the present invention, using the heat pump energy storage system based on heat recovery and cooling, includes the following steps:

[0029] Charging steps: Electricity is required to drive the first and second compressors to run. The heat pump working fluid is compressed by the first compressor and then enters the heat pump regenerator to absorb heat. It is then heated in the external heating device and then pressurized by the second compressor to form a high-temperature and high-pressure gas.

[0030] The high-temperature and high-pressure gas enters the first heat exchanger to exchange heat with the high-temperature heat storage module, then enters the heat pump regenerator to release heat, and then enters the fourth heat exchanger and the heat pump cooler to be cooled. Then it enters the first expander to do work and become low-temperature and low-pressure gas. The low-temperature and low-pressure gas enters the second heat exchanger to exchange heat with the low-temperature heat storage module, and after absorbing heat from the heat pump cooler, it returns to the inlet of the first compressor.

[0031] Discharge steps: The high-temperature and high-pressure working fluid leaving the outlet of the third heat exchanger enters the second expander to do work and drive the power generation device to generate electricity. Then it releases heat in the heat engine regenerator and the fifth heat exchanger, becoming a low-temperature and low-pressure state. The low-temperature and low-pressure working fluid is compressed by the third compressor and then enters the heat engine regenerator for preheating. Then it absorbs the heat stored in the high-temperature heat storage module in the third heat exchanger and becomes a high-temperature and high-pressure state again.

[0032] Preferably, in the charging step, the gas after heat exchange in the first heat exchanger enters the heat pump regenerator to release heat, and after releasing heat, the waste heat is output through the fourth heat exchanger for heating, and then enters the heat pump cooler to be cooled.

[0033] During the discharge process, the working fluid, after being heated by the heat engine regenerator, enters the fifth heat exchanger to transfer heat to the heat user and becomes a low-temperature and low-pressure state.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. This invention utilizes a regenerative-cooling-work recovery heat pump cycle. The heat pump regenerator recovers the residual heat of the working fluid after it leaves the first heat exchanger, and the heat pump cooler recovers the residual cold of the working fluid after it leaves the second heat exchanger. The expander recovers a portion of the expansion work. Through the two-stage compression intermediate heating and regenerative-cooling design, the pressure ratio and temperature ratio are reduced, the development difficulty of thermomechanical systems is lowered, and the electro-thermal conversion performance of the heat pump is improved.

[0036] 2. This invention decouples thermal storage and cold storage, avoiding energy waste or efficiency sacrifices caused by matching thermal and cold storage temperatures during discharge. The high-temperature thermal storage end can be directly integrated with existing solar thermal power plants, resulting in low overall costs; the low-temperature cold storage end can fully utilize cold energy to meet the needs of chemical gas liquefaction and cryogenic separation technology.

[0037] 3. This invention can generate high-temperature steam or hot water during both charging and discharging processes, meeting the heating needs of district heating and industrial and agricultural industries.

[0038] 4. This invention proposes a novel heat pump energy storage system based on heat recovery-cooling recovery-work recovery. In large energy bases, compared with direct electric heating heat storage, the existing solar thermal collectors and heat pumps in solar thermal power plants can achieve an electro-thermal amplification effect, further improving the electro-electric conversion efficiency.

[0039] 5. This invention has two major application scenarios. On the one hand, it can be coupled with renewable energy storage for solar photovoltaic or wind power consumption to improve the stability of the power system. On the other hand, it can be used for the renovation of decommissioned thermal power plants to replace the boilers of old coal-fired units, build independent energy storage power stations, play a peak-shaving role, and provide support for the construction of a high proportion of new power systems. Attached Figure Description

[0040] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0041] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0042] Figure 2 This is a charging flowchart of the present invention;

[0043] Figure 3 This is a discharge flowchart of the present invention.

[0044] The diagram shows:

[0045] First compressor 1; Third heat exchanger 11

[0046] Heat pump regenerator 2 Power generation unit 12

[0047] Second compressor 3, air tank 13

[0048] First heat exchanger 4, liquid storage tank 14

[0049] Fourth heat exchanger 5 External heating device 15

[0050] Heat pump recooler 6 Second expander 16

[0051] First expander 7, heat engine regenerator 17

[0052] Second heat exchanger 8 Fifth heat exchanger 18

[0053] High-temperature heat storage tank 9 Third compressor 19

[0054] Low-temperature thermal storage tank 10 Detailed Implementation

[0055] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0056] This invention discloses a heat pump energy storage system based on regenerative and recooling and its operation method. The heat pump regenerator can recover the waste heat of the working fluid, and the heat pump recooler can recover the waste cold of the working fluid. Through the two-stage compression intermediate heating and regenerative and recooling design, the pressure ratio and temperature ratio are reduced, the development difficulty of thermomechanical systems is reduced, and the electro-thermal conversion performance of the heat pump is improved.

[0057] Example 1

[0058] This embodiment provides a novel heat pump energy storage system based on heat recovery-cooling recovery-work recovery, such as... Figure 1 As shown, the system includes a heat pump circuit, a high-temperature thermal energy storage module, a low-temperature cold energy storage module, and a power generation module. Both the high-temperature thermal energy storage module and the low-temperature cold energy storage module are heat exchanged with the heat pump circuit, and the power generation module is heat exchanged with the high-temperature thermal energy storage module. Both the heat pump circuit and the power generation module are connected to an external power grid. The power generation module supplies power to the external power grid. The heat pump circuit, driven by the electricity to be consumed, absorbs heat from the low-temperature cold energy storage module and releases heat to the high-temperature thermal energy storage module. The low-temperature cold energy storage module stores low-temperature cold energy, and the high-temperature thermal energy storage module stores high-temperature heat energy.

[0059] The system helps reduce the compressor's pressure ratio and temperature ratio, improving heat pump performance. Simultaneously, it decouples cold and heat storage, avoiding energy waste caused by temperature mismatch. The heat pump circuit is driven by the electricity required for consumption, absorbing heat from the low-temperature cold storage module and releasing heat to the high-temperature heat storage module. Low-temperature cold energy is stored in the low-temperature cold storage module, and high-temperature heat energy is stored in the high-temperature heat storage module. During peak electricity consumption periods, the high-temperature heat energy stored in the high-temperature heat storage module can drive the power generation module to supply electricity to the grid. The low-temperature cold energy in the low-temperature cold storage module is used for the production of liquid fuels or other chemical gas liquefaction needs, as well as for cryogenic separation technology.

[0060] The heat pump circuit consists of a first compressor 1, a heat pump regenerator 2, an external heating device 15, a second compressor 3, a first heat exchanger 4, a fourth heat exchanger 5, a heat pump cooler 6, an expander 7, and a second heat exchanger 8 connected sequentially via pipelines. Preferably, the working fluid in the heat pump circuit is air. The cold-side inlet of the heat pump regenerator 2 is connected to the outlet of the first compressor 1, the cold-side outlet of the heat pump regenerator 2 is connected to the inlet of the external heating device 15, the hot-side inlet of the heat pump regenerator 2 is connected to the air outlet of the first heat exchanger 4, and the hot-side outlet of the heat pump regenerator 2 is connected to the fourth heat exchanger 5; the hot-side inlet of the heat pump cooler 6 is connected to the fourth heat exchanger 5, the hot-side outlet of the heat pump cooler 6 is connected to the inlet of the expander 7, the cold-side inlet of the heat pump cooler 6 is connected to the air outlet of the second heat exchanger 8, and the cold-side outlet of the heat pump cooler 6 is connected to the inlet of the first compressor 1.

[0061] Optionally, the circulating medium in the heat pump circuit is one of air, argon, nitrogen, helium, carbon dioxide, etc. Preferably, the external heating device 15 installed between the cold-side outlet of the heat pump regenerator 2 and the inlet of the second compressor 3 is a solar thermal collector device of a solar thermal power plant, which can be used to heat the heat pump working fluid. Optionally, the cold-side outlet of the heat pump regenerator 2 can also be directly connected to the inlet of the second compressor 3, without using the external heating device 15 for heating. Further, the first and second heat exchangers and the heat pump regenerator can all be one or more heat exchangers connected in series.

[0062] The high-temperature thermal storage module consists of a first heat exchanger 4, a high-temperature thermal storage tank 9, a third heat exchanger 11, and a low-temperature thermal storage tank 10, connected sequentially by pipelines. The inlet of the first heat exchanger 4 is connected to the low-temperature thermal storage tank 10, and the outlet of the first heat exchanger 4 is connected to the high-temperature thermal storage tank 9. The inlet of the third heat exchanger 11 is connected to the high-temperature thermal storage tank 9, and the outlet of the third heat exchanger 11 is connected to the low-temperature thermal storage tank 10. Preferably, the thermal storage medium used in the high-temperature thermal storage module is molten salt.

[0063] The low-temperature cold storage module consists of a gas storage tank 13, a second heat exchanger 8, and a liquid storage tank 14 connected in sequence by pipelines.

[0064] Optionally, the circulating medium of the cryogenic cold storage module is one or more of the following, including but not limited to methanol, ethanol, propane, pentane, hydrogen, ammonia, nitrogen, oxygen, and natural gas. Preferably, the cold storage medium of the cryogenic cold storage module is ammonia.

[0065] The power generation module consists of the third heat exchanger 11, the second expander 16, the heat engine regenerator 17, the fifth heat exchanger 18, and the third compressor 19 connected sequentially via pipelines. The hot-side inlet of the heat engine regenerator 17 is connected to the outlet of the second expander 16, and the hot-side outlet of the heat engine regenerator 17 is connected to the fifth heat exchanger 18. The cold-side inlet of the heat engine regenerator 17 is connected to the outlet of the third compressor 19, and the cold-side outlet of the heat engine regenerator 17 is connected to the carbon dioxide inlet of the third heat exchanger 11. The second expander 16 is used to drive the power generation device 12 to generate electricity through expansion.

[0066] The power generation device employs one or more of the following power generation methods, including but not limited to supercritical carbon dioxide power cycle, steam power generation, organic Rankine cycle, and air Brayton cycle.

[0067] Optionally, the medium circulating in the power generation module is one or more of, including but not limited to, carbon dioxide, water vapor, air, and argon. Preferably, the power generation medium in the power generation module is supercritical carbon dioxide.

[0068] Example 2

[0069] This embodiment provides an operation method for a novel heat pump energy storage system based on heat recovery-cooling recovery-work recovery, including: a charging step and a discharging step;

[0070] The charging process in this embodiment is as follows: Figure 2As shown: The photovoltaic power, wind power, or off-peak electricity from the power grid that needs to be consumed drives the operation of the first compressor 1 and the second compressor 3. After being compressed by the first compressor 1, the air enters the heat pump regenerator 2 to absorb heat, and then is further heated by solar energy in the external heating device 15, preferably a solar collector. After passing through the second compressor 3, it becomes a high-temperature, high-pressure gas. The high-temperature, high-pressure gas enters the first heat exchanger 4 to transfer heat to the molten salt, and then enters the heat pump regenerator 2 again to release heat. Finally, it passes through the fourth heat exchanger 5 to output the waste heat for heating. The air then enters the heat pump cooler 6 to be cooled, and then enters the expander 7 to expand and do work, becoming a low-temperature, low-pressure state. In the second heat exchanger 8, it transfers the cold energy to the ammonia in the low-temperature cold storage module, and after absorbing heat from the heat pump cooler 6, it returns to the inlet of the first compressor 1. During the charging process, the heat pump regenerator 2 can recover the waste heat from the air in the first heat exchanger 4, the heat pump cooler 6 can recover the waste cold energy after the air leaves the second heat exchanger 8, and the expander 7 can recover a portion of the expansion work.

[0071] During charging, molten salt from the cryogenic heat storage tank 10 absorbs heat in the first heat exchanger 4 and then enters the high-temperature heat storage tank 9; in the cryogenic cold storage module, ammonia from the gas storage tank 13 is cooled and liquefied in the second heat exchanger 8 and then enters the liquid storage tank 14. Gas feedstock is periodically replenished to the gas storage tank 13, and liquid ammonia is transported from the liquid storage tank for industrial needs.

[0072] The discharge process in this embodiment is as follows: Figure 3 As shown: When peak shaving is required, the discharge process is initiated. The high-temperature, high-pressure carbon dioxide working fluid leaving the carbon dioxide outlet of the third heat exchanger 11 enters the second expander 16 to perform work and drive the power generation device 12 to generate electricity, relieving peak electricity demand pressure. Then, it releases heat in the heat engine regenerator 17 and finally enters the fifth heat exchanger 18 to transfer heat to the heat users, becoming a low-temperature, low-pressure state. The low-temperature, low-pressure carbon dioxide working fluid is compressed by the third compressor 19 and then enters the heat engine regenerator 17 for preheating. Then, it absorbs the heat stored in the third heat exchanger 19 and returns to the high-temperature, high-pressure state. In the high-temperature heat storage module during the discharge process, the molten salt from the high-temperature heat storage tank 9 releases heat to the carbon dioxide in the third heat exchanger 11 and then returns to the low-temperature heat storage tank 10.

[0073] Both charging and discharging processes can generate high-temperature steam or hot water to meet the heating needs of district heating and industrial and agricultural applications. During charging, heat energy can be supplied to heat users through the fourth heat exchanger, and during discharging, waste heat from the power generation unit can be supplied to heat users through the fifth heat exchanger. Furthermore, both the fourth and fifth heat exchangers can be one or more heat exchangers connected in series.

[0074] In this embodiment, the system can generate high-temperature heat energy above 550℃ and low-temperature cold energy below -50℃, with a charge-discharge efficiency exceeding 60%. The heat pump proposed in this embodiment uses air as the working fluid, which is lower in cost compared to argon, helium, and nitrogen, while also having lower sealing requirements, a wider adjustable pressure range, and higher technical feasibility. The power generation module proposed in this embodiment uses supercritical carbon dioxide as the working fluid, exhibiting high power density, a smaller unit size, and higher power generation efficiency.

[0075] In the description of this application, it should be understood that the parameters such as temperature mentioned are merely illustrative for ease of understanding and are not intended to limit specific parameters; the description of the working fluid state only indicates the relative changes in the state of the working fluid during the cycle and is not intended to limit specific state parameters.

[0076] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0077] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A heat pump energy storage system based on heat recovery and cooling, characterized in that, It includes a heat pump circuit, a high-temperature thermal storage module, a low-temperature cold storage module, and a power generation module. The high-temperature thermal storage module and the low-temperature cold storage module are both heat exchanged with the heat pump circuit, and the power generation module is heat exchanged with the high-temperature thermal storage module. Both the heat pump circuit and the power generation module are connected to the external power grid. The power generation module is used to supply power to the external power grid. The heat pump circuit is driven by the power to be consumed and is used to absorb heat from the low-temperature cold storage module and release heat to the high-temperature heat storage module. The low-temperature cold storage module is used to store low-temperature cold energy, and the high-temperature heat storage module is used to store high-temperature heat energy. The heat pump circuit includes a first compressor (1), a second compressor (3), a heat pump regenerator (2), a first heat exchanger (4), a fourth heat exchanger (5), a heat pump cooler (6), a first expander (7), and a second heat exchanger (8). The first compressor (1), the cold side of the heat pump regenerator (2), the second compressor (3), the first heat exchanger (4), the hot side of the heat pump regenerator (2), the fourth heat exchanger (5), the hot side of the heat pump cooler (6), the first expander (7), the second heat exchanger (8), and the cold side of the heat pump cooler (6) are connected in sequence through pipelines to form a loop; The first heat exchanger (4) is used for heat exchange with the high-temperature thermal storage module, and the second heat exchanger (8) is used for heat exchange with the low-temperature cold storage module. The heat pump circuit also includes an external solar heating device (15). The cold side inlet of the heat pump regenerator (2) is connected to the outlet of the first compressor (1), the cold side outlet of the heat pump regenerator (2) is connected to the inlet of the external solar heating device (15), and the hot side inlet of the heat pump regenerator (2) is connected to the outlet of the heat pump working fluid of the first heat exchanger (4). The heat pump regenerator (2) has its hot side outlet connected to the fourth heat exchanger (5), which is used to output waste heat for heating. The heat pump cooler (6) has its hot side inlet connected to the fourth heat exchanger (5). The hot side outlet of the heat pump cooler (6) is connected to the inlet of the first expander (7), the outlet of the first expander (7) is connected to the heat pump working fluid inlet of the second heat exchanger (8), the cold side inlet of the heat pump cooler (6) is connected to the heat pump working fluid outlet of the second heat exchanger (8), and the cold side outlet of the heat pump cooler (6) is connected to the inlet of the first compressor (1). Both the first compressor (1) and the second compressor (3) are connected to an external power grid and are driven by the power that needs to be consumed; The power generation module includes a third heat exchanger (11), a second expander (16), a heat engine regenerator (17), a fifth heat exchanger (18), and a third compressor (19) connected in sequence by pipelines. The fifth heat exchanger (18) is used to output waste heat for heating. The outlet of the third heat exchanger (11) is connected to the inlet of the second expander (16), the hot-side inlet of the heat engine regenerator (17) is connected to the outlet of the second expander (16), the hot-side outlet of the heat engine regenerator (17) is connected to the fifth heat exchanger (18), the cold-side inlet of the heat engine regenerator (17) is connected to the outlet of the third compressor (19), and the cold-side outlet of the heat engine regenerator (17) is connected to the inlet of the third heat exchanger (11). The second expander (16) is connected to a power generation device (12) and is used to drive the power generation device (12) to generate electricity. The power generation device (12) is connected to an external power grid.

2. The heat pump energy storage system based on heat recovery and cooling according to claim 1, characterized in that, The high-temperature thermal storage module includes a high-temperature thermal storage tank (9), a third heat exchanger (11), a low-temperature thermal storage tank (10), and a first heat exchanger (4), which are connected in sequence through pipelines to form a loop. The inlet of the heat storage medium of the first heat exchanger (4) is connected to the low-temperature heat storage tank (10), the outlet of the heat storage medium of the first heat exchanger (4) is connected to the high-temperature heat storage tank (9), the inlet of the heat storage medium of the third heat exchanger (11) is connected to the high-temperature heat storage tank (9), and the outlet of the heat storage medium of the third heat exchanger (11) is connected to the low-temperature heat storage tank (10). The first heat exchanger (4) is a shared component of the high-temperature heat storage module and the heat pump circuit, and is used for heat exchange between the high-temperature heat storage module and the heat pump circuit. The third heat exchanger (11) is a shared component of the high-temperature heat storage module and the power generation module, and is used for heat exchange between the high-temperature heat storage module and the power generation module.

3. The heat pump energy storage system based on heat recovery and cooling according to claim 1, characterized in that, The high-temperature thermal storage module uses molten salt as the thermal storage medium.

4. The heat pump energy storage system based on heat recovery and cooling according to claim 1, characterized in that, The low-temperature cold storage module includes a gas storage tank (13), a second heat exchanger (8), and a liquid storage tank (14), which are connected in sequence by pipelines. The second heat exchanger (8) is a shared component between the low-temperature cold storage module and the heat pump circuit, and is used for heat exchange between the low-temperature cold storage module and the heat pump circuit.

5. The heat pump energy storage system based on heat recovery and cooling according to claim 1, characterized in that, The cold storage medium of the low-temperature cold storage module is one or more of the following, including but not limited to methanol, ethanol, propane, pentane, hydrogen, ammonia, nitrogen, oxygen, and natural gas.

6. The heat pump energy storage system based on heat recovery and cooling according to claim 1, characterized in that, The working fluid of the heat pump circuit is one of air, argon, nitrogen, helium, carbon dioxide, etc., and the working fluid of the power generation module is one or more of carbon dioxide, water vapor, air, argon, etc., including but not limited to.

7. An operation method for a heat pump energy storage system based on heat recovery and cooling, characterized in that, The heat pump energy storage system based on heat recovery and cooling as described in any one of claims 1-6 includes the following steps: Charging steps: The first compressor (1) and the second compressor (3) need to be powered by electricity. The heat pump working fluid is compressed by the first compressor (1) and enters the heat pump regenerator (2) to absorb heat. Then it is heated in the external heating device (15) and then pressurized by the second compressor (3) to form a high temperature and high pressure gas. The high-temperature and high-pressure gas enters the first heat exchanger (4) to exchange heat with the high-temperature heat storage module, and then enters the heat pump regenerator (2) to release heat. It then enters the heat pump cooler (6) to be cooled, and then enters the first expander (7) to do work and become low-temperature and low-pressure gas. The low-temperature and low-pressure gas enters the second heat exchanger (8) to exchange heat with the low-temperature heat storage module, and absorbs heat from the heat pump cooler (6) before returning to the inlet of the first compressor (1). Discharge steps: The working fluid in the high temperature and high pressure state that leaves the outlet of the third heat exchanger (11) enters the second expander (16) to do work and drive the power generation device (12) to generate electricity. Then it releases heat in the heat engine regenerator (17) and becomes a low temperature and low pressure state. The working fluid in the low temperature and low pressure state is compressed by the third compressor (19) and enters the heat engine regenerator (17) for preheating. Then it absorbs the heat stored in the high pressure heat storage module in the third heat exchanger (11) and becomes a high temperature and high pressure state again. During the charging process, the gas after heat exchange in the first heat exchanger (4) enters the heat pump regenerator (2) to release heat. After releasing heat, the waste heat is output through the fourth heat exchanger (5) for heating, and then enters the heat pump cooler (6) to be cooled. During the discharge step, the working fluid, after being heated by the heat engine regenerator (17), enters the fifth heat exchanger (18) to transfer heat to the heat user and becomes a low temperature and low pressure state.

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