Geothermal energy storage system and method coupled with thermal power generation

Abstract

The invention discloses a geothermal energy storage system and method coupled with thermal power generation, and relates to the technical field of energy storage equipment. The geothermal energy storage system for coupling thermal power generation comprises a steam turbine cylinder, a steam pipeline and a first steam exhaust pipeline, an outlet of the steam pipeline is connected to a steam inlet of the steam turbine cylinder, a steam exhaust port of the steam turbine cylinder is connected to an inlet of the first steam exhaust pipeline, and the first steam exhaust pipeline is horizontally connected with a second steam exhaust pipeline; a control valve is arranged on the first steam exhaust pipeline, and an outlet of the first steam exhaust pipeline is connected to an inlet of an underground heat pipe network buried in an underground soil layer; an outlet of the underground heat pipe network is connected to an inlet of the one-way valve, and an outlet of the one-way valve is connected to the second steam exhaust pipeline. According to the system, the unit can quickly reduce the power generation load on the premise of not greatly adjusting the combustion condition of the boiler, and the problems of slow response, insufficient thermoelectric decoupling capability, low energy efficiency of low-load operation and aggravated equipment loss when the thermal power unit participates in the deep peak regulation of the power grid are solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of energy storage devices, and particularly relates to a geothermal energy storage system and method coupled with thermal power generation. BACKGROUND

[0002] Currently, thermal power generating units undertake the dual tasks of base load and peak shaving in the power system, and their operation flexibility has become a key capability to support high proportion of new energy grid connection. In order to improve the peak shaving performance, the existing technology generally adopts the following paths: turbine body modification (such as low-pressure cylinder zero output), boiler side deep temperature adjustment, and external storage system. Among them, the external storage scheme has attracted attention because it does not change the main equipment and has a short engineering implementation cycle. The mainstream technologies include electrode boiler coupled hot water tank, molten salt storage system and phase change material storage device. Such schemes convert the excess steam or electric energy of the unit into heat energy stored in artificially constructed heat storage medium, and release it for heating or re-generation when needed, which has been demonstrated in some 300-600 MW class thermal power units.

[0003] However, the above-mentioned external storage scheme relies on new large pressure vessels and supporting soil structures, resulting in high initial investment, large land occupation, high system complexity, and problems such as high heat loss rate (daily heat loss up to 1.2%-2.5%) of the heat storage medium (such as water, molten salt), limited service life, and strict winter anti-freezing operation and maintenance requirements. More importantly, the thermal interface of the existing thermal power unit is mostly located in the medium and low pressure extraction section or the condensate water system, which has low steam grade (temperature generally below 200℃) and small heat storage capacity per unit mass of steam, making it difficult to match the high-quality sensible heat potential contained in the high temperature and high pressure exhaust section of the steam turbine, resulting in a large amount of high-grade exhaust energy being abandoned during deep adjustment, which restricts the further improvement of the lower limit of unit adjustment and response speed. SUMMARY

[0004] The purpose of the present application is to overcome the above-mentioned problems, and to provide a geothermal energy storage system and method coupled with thermal power generation, to solve the technical problems of slow response, insufficient thermal decoupling capability, low efficiency of low load operation, and intensified equipment wear of the existing thermal power unit when participating in deep peak shaving of the power grid.

[0005] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions: In a first aspect, the present application provides a geothermal energy storage system coupled with thermal power generation, comprising a steam turbine cylinder, a steam pipeline and a first exhaust pipeline, the outlet of the steam pipeline is connected to the steam inlet of the steam turbine cylinder, the steam exhaust port of the steam turbine cylinder is connected to the inlet of the first exhaust pipeline, and the first exhaust pipeline is horizontally connected with a second exhaust pipeline; A control valve is arranged on the first exhaust pipeline, and the outlet of the first exhaust pipeline is connected to the inlet of an underground heat pipe network buried in the underground soil layer. The outlet of the underground heating network is connected to the inlet of a one-way valve, and the outlet of the one-way valve is connected to the second exhaust pipe.

[0006] A further improvement of the present invention is that the control valve is an electric regulating valve or a pneumatic regulating valve.

[0007] A further improvement of the present invention is that the control valve is located on the first exhaust pipe and below the connection between the first exhaust pipe and the second exhaust pipe.

[0008] A further improvement of the present invention is that the underground heating network is buried at a depth of 50~300m.

[0009] A further improvement of the present invention is that the underground heating network is one of U-shaped buried pipe, spiral coil pipe or multi-pass direct buried pipe.

[0010] A further improvement of the present invention is that the outlet of the second exhaust pipe leads to a reheater or a condenser.

[0011] A further improvement of the present invention is that it also includes a geothermal well, a geothermal well inlet pipe, and a geothermal well outlet pipe; the geothermal well is vertically drilled in the underground soil layer and is located within the heat influence radius of the underground heat pipe network.

[0012] A further improvement of the present invention is that the geothermal well is provided with a wellhead, which has an inlet end and an outlet end; one end of the geothermal well inlet pipe is connected to the inlet end of the geothermal well well, and one end of the geothermal well outlet pipe is connected to the outlet end of the geothermal well well.

[0013] Secondly, the present invention also provides a geothermal energy storage method coupled with thermal power generation, comprising the following steps: During normal operation of the thermal power unit, the control valve is in the closed state, and all the steam discharged from the turbine cylinder flows into the second exhaust pipeline through the first exhaust pipeline and is delivered to the reheater or condensing equipment. During deep adjustment or rapid load reduction of thermal power units, the control valve is in the open state. Part of the steam discharged from the turbine cylinder flows directly into the second steam pipeline through the first exhaust pipeline, and the other part is led out through the control valve and input into the underground heat pipe network buried in the underground soil layer. The steam flows within the underground heat pipe network, transferring its heat to the surrounding underground soil layers. Steam that has been heated by the underground heating network flows out from its outlet and enters the second exhaust steam pipeline through a one-way valve. The second exhaust steam line delivers steam from the first exhaust steam line and steam from the one-way valve to the reheater or condenser.

[0014] A further improvement of the present invention is that it further includes the following steps: After the underground heating network has been running for a predetermined period of time, low-temperature water is introduced into the geothermal well inlet pipeline, so that the low-temperature water enters the underground soil layer through the geothermal well. Low-temperature water flows in the underground soil, absorbs heat from the surrounding environment and heats up, and is then drawn out through the geothermal well outlet pipe.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a geothermal energy storage system coupled with thermal power generation. By installing a control valve on the first exhaust steam pipeline and connecting it to an underground thermal pipeline network buried in the soil, a channel is constructed to divert turbine exhaust steam to underground thermal storage. When the thermal power unit needs deep peak shaving or rapid load reduction, the control valve is opened to guide steam into the underground thermal pipeline network. As the steam flows through the network, it continuously transfers its heat energy to the surrounding soil for storage. The cooled working fluid then returns to the system via a one-way valve into the second exhaust steam pipeline. This design allows the unit to rapidly reduce its power generation load without significantly adjusting boiler combustion conditions, with a significantly faster response speed than traditional load reduction methods. It effectively solves the problems of slow response, insufficient thermal-electric decoupling capability, low energy efficiency under low load, and increased equipment wear faced by thermal power units participating in deep grid peak shaving. Simultaneously, this solution utilizes the heat generated during load reduction... The system converts potentially wasted steam heat into geothermal energy and stores it underground, achieving spatial and temporal energy transfer and efficient utilization. When needed, the stored heat can be extracted through an independent geothermal well system (geothermal well inlet and outlet pipes) for heating or other purposes. This not only significantly improves the overall energy utilization efficiency and reduces carbon emissions, but also creates additional revenue for the power plant. Furthermore, since the diverted steam heat is stored in the soil instead of being directly emitted, thermal pollution to the environment is reduced. By maintaining the boiler at a relatively stable load, the system reduces equipment lifespan loss caused by frequent and drastic load adjustments. The one-way valve ensures unidirectional flow of the working fluid, preventing backflow from interfering with system stability. Overall, this system improves the peak-shaving flexibility and response speed of thermal power units, promotes the consumption of renewable energy, and achieves cascaded energy utilization and energy conservation and emission reduction, demonstrating significant economic benefits and environmental value.

[0016] This invention also provides a geothermal energy storage method coupled with thermal power generation. This method intelligently switches the steam flow direction by controlling the opening and closing of valves. During normal unit operation, all steam is used for power generation. During periods of deep regulation or rapid load reduction, some steam is diverted to the underground heat pipe network, utilizing the large-scale heat storage capacity of the underground soil to temporarily store excess heat. This design ensures both rapid load response of the unit and avoids energy waste through geothermal energy storage. Its core benefit lies in achieving heat and power decoupling: after the underground heat pipe network stores the heat energy, the system can extract heat for heating through independent geothermal well loops when needed, forming a cycle of "seasonal energy storage + inter-temporal utilization." This method not only significantly improves the unit's peak-shaving flexibility but also reduces unit coal consumption by recovering waste steam heat, while reducing equipment wear and carbon emissions during low-load operation, creating dual economic benefits for power plants: peak-shaving revenue and added value from heating. Attached Figure Description

[0017] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Furthermore, the shapes and proportions of the components in the drawings are merely illustrative to aid in understanding the invention and do not specifically limit the shapes and proportions of the components of the invention.

[0018] Figure 1 This is a schematic diagram of the geothermal energy storage system coupled with thermal power generation according to the present invention.

[0019] The components include: 1. Steam turbine cylinder; 2. Steam pipeline; 3. First exhaust steam pipeline; 4. Control valve; 5. Underground soil layer; 6. Underground heat pipe network; 7. Geothermal well inlet pipeline; 8. Geothermal well outlet pipeline; 9. One-way valve; 10. Second exhaust pipeline. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0022] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0023] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention 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, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0026] The present invention will now be described in further detail with reference to the accompanying drawings: Under deep peak shaving or rapid load reduction conditions, existing thermal power units often have large amounts of high-temperature, high-pressure exhaust steam forced into reheaters or condensing systems because it cannot perform work in time. This results in the waste of high-quality thermal energy and exacerbates unit regulation lag and increased coal consumption. Traditional thermal energy storage solutions (such as electric boilers with water tanks or molten salt systems) suffer from high investment, large footprint, short lifespan, and low integration with existing units. To address these issues, this application proposes a geothermal energy storage system coupled with thermal power generation. By reconfiguring the exhaust steam energy flow, it utilizes natural underground soil layers as a large-capacity, non-construction thermal energy storage medium to achieve in-situ, long-term, and low-cost storage of waste heat from thermal power plants.

[0027] like Figure 1As shown, the present invention provides a geothermal energy storage system coupled with thermal power generation, including a turbine cylinder 1, a steam pipeline 2, and a first exhaust pipeline 3. The outlet of the steam pipeline 2 is connected to the steam inlet of the turbine cylinder 1, and the exhaust port of the turbine cylinder 1 is connected to the inlet of the first exhaust pipeline 2. The first exhaust pipeline 3 is horizontally connected to a second exhaust pipeline 10. A control valve 4 is installed on the first exhaust pipeline 3, and the outlet of the first exhaust pipeline 3 is connected to the inlet of an underground thermal pipeline network 6 buried in the underground soil layer 5. The outlet of the underground thermal pipeline network 6 is connected to the inlet of a one-way valve 9, and the outlet of the one-way valve 9 is connected to the second exhaust pipeline 10.

[0028] In practice, turbine cylinder 1 can be a high-pressure cylinder from a supercritical unit, with a shell made of chromium-molybdenum steel to withstand high-temperature and high-pressure steam. The steam inlet and outlet are connected to the pipeline via alloy steel flanges. Steam pipeline 2 and the first exhaust pipeline 3 are made of seamless steel pipes, covered with insulation material to reduce heat loss. The valve body of control valve 4 is made of cast steel and connected to the first exhaust pipeline 3 via flanges. The underground heat pipe network 6 uses high-density polyethylene (HDPE) pipes, which have good corrosion resistance and long service life. After the network is buried underground, it is backfilled with sand to ensure heat exchange efficiency. One-way valve 9 is a swing check valve with a stainless steel valve disc to prevent backflow of the working fluid. All connections can be sealed by welding or standard pipe fittings. When the system is working, under conditions requiring rapid load reduction, control valve 4 opens, and some steam is diverted from the first exhaust pipeline 3 to the underground heat pipe network 6. The steam heat is absorbed and stored by the surrounding soil, and the cooled working fluid returns to the system via the second exhaust pipeline 10 through one-way valve 9. This system enables the transfer and storage of steam thermal energy, rather than its direct waste, thereby improving energy utilization efficiency and providing the unit with a fast and flexible means of load regulation.

[0029] It should be noted that multiple independent steam pipeline branches can be configured according to the actual number of cylinders of the steam turbine, and each branch is connected to the corresponding steam turbine cylinder 1 to achieve more efficient heat energy recovery and utilization.

[0030] In some embodiments, the control valve 4 is an electrically operated or pneumatically operated regulating valve. The electrically operated regulating valve can be driven by an intelligent electric actuator, which has the advantages of long control signal transmission distance, high precision, and easy integration into the power plant's distributed control system (DCS) for automatic regulation. The pneumatically operated regulating valve can be driven by a cylinder, which has the advantages of fast action speed, good explosion-proof performance, and suitability for specific environments. The valve core can adopt a cage-type or single-seat structure to match different flow regulation characteristics. In practical applications, other models of this component can also be selected, and this application embodiment does not limit this.

[0031] In some embodiments, the control valve 4 is located on the first exhaust steam pipe 3, below the connection between the first exhaust steam pipe 3 and the second exhaust steam pipe 10. Specifically, this connection can be designed as a tee fitting, with the control valve 4 installed on the branch of this tee fitting leading to the underground heating network 6, and its inlet centerline elevation lower than the centerline elevation of the connection, creating a certain drop. This arrangement utilizes gravity to ensure natural steam flow during diversion and facilitates the flow of condensate generated after heat exchange downstream of the valve.

[0032] In some embodiments, the underground heat pipe network 6 is buried at a depth of 50~300m, utilizing the earth as a huge heat capacity for cross-seasonal heat storage, ensuring a sufficiently large heat exchange area and heat capacity, and achieving efficient energy storage.

[0033] In some embodiments, the underground heating network 6 is one of U-shaped buried pipes, spiral coiled pipes, or multi-pass direct-buried pipes. Specifically, a U-shaped buried pipe can consist of two HDPE pipes connected at the bottom with a U-shaped elbow, resulting in a simple structure; a spiral coiled pipe involves winding a single pipe into a cylindrical shape, providing a large heat exchange area per unit well depth; a multi-pass direct-buried pipe involves setting multiple parallel or series loops within the well, resulting in a uniform distribution of flow resistance. The pipe diameter can be selected from DN40 to DN100. By increasing the contact area between the pipe network and the soil, heat transfer is enhanced, improving the system's adaptability and heat exchange efficiency.

[0034] In some embodiments, the outlet of the second exhaust pipe 10 leads to a reheater or condenser, allowing the working fluid that has completed the diversion and heat exchange functions to safely return to the main system, ensuring the recycling of the system working fluid and the integrity of the thermodynamic process.

[0035] In some embodiments, the system further includes a geothermal well, a geothermal well inlet pipe 7, and a geothermal well outlet pipe 8. The geothermal well is vertically drilled in the underground soil layer 5 and located within the heat-affected radius of the underground heat pipe network 6. The geothermal well has a wellhead with an inlet end and an outlet end. One end of the geothermal well inlet pipe 7 is connected to the inlet end of the geothermal well, and one end of the geothermal well outlet pipe 8 is connected to the outlet end of the geothermal well. In specific implementations, the drilling depth of the geothermal well can be matched with the burial depth of the underground heat pipe network 6, and the well casing is made of steel pipe or HDPE pipe. The geothermal well inlet pipe 7 and the geothermal well outlet pipe 8 can be made of PP-R pipe and sealed by a wellhead device. The heat-affected radius can be determined by thermal response testing, typically 5-15 meters, to ensure effective extraction of stored heat. The inlet end and outlet end are connected to the heat exchange zone at the bottom of the well through an internal structure. Pipeline connections are made using threads or flanges. By forming a closed water cycle, low-temperature water is injected from the inlet, heated underground, and then flows out from the outlet, providing a stable and reliable geothermal extraction path.

[0036] The present invention also provides a geothermal energy storage method based on the above-mentioned system coupled with thermal power generation, comprising the following steps: During normal operation of the thermal power unit, control valve 4 is in the closed state, and all the steam discharged from turbine cylinder 1 flows into the second exhaust pipeline 10 through the first exhaust pipeline 3 and is delivered to the reheater or condensing equipment. During the deep adjustment or rapid load reduction of the thermal power unit, the control valve 4 is in the open state. Part of the steam discharged from the turbine cylinder 1 flows directly into the second steam pipeline 10 through the first exhaust pipeline 3, and the other part is led out through the control valve 4 and input into the underground heat pipe network 6 buried in the underground soil layer 5. The steam flows within the underground heat pipe network 6, transferring its heat to the surrounding underground soil layer 5. Steam that has been heat-exchanged through the underground heating network 6 flows out from its outlet and enters the second exhaust steam pipeline 10 through the one-way valve 9; The second steam line 10 delivers steam from the first steam line 3 and steam from the one-way valve 9 to the reheater or condenser.

[0037] In practice, "normal operation" refers to the period when the unit load rate is between 80% and 100%, during which control valve 4 receives a shutdown command from the DCS system. "Deep adjustment or rapid load reduction" refers to the period when the load rate needs to be reduced to below 30% within a short time. Control valve 4 opens according to a predetermined program based on the frequency regulation command, and the diversion ratio can be continuously adjusted by the valve opening degree, for example, opening to 50%. The steam flow velocity in the underground heat pipe network 6 is controlled at 2-5 m / s to ensure sufficient heat exchange. By switching the steam flow direction through control valve 4, excess heat energy is temporarily stored underground, achieving rapid and smooth adjustment of the unit load and converting previously wasted heat energy into reusable geothermal energy.

[0038] Furthermore, after the underground heating network 6 has been operating continuously for a predetermined time, low-temperature water is introduced into the geothermal well inlet pipe 7, allowing it to enter the underground soil layer 5 via the geothermal well. The low-temperature water flows within the underground soil layer 5, absorbing heat from the surrounding environment and heating up before being led out through the geothermal well outlet pipe 8. In practice, the "predetermined time" can be several hours or days to ensure the soil temperature field rises. The low-temperature water can be supplied by a makeup water pump, and the water temperature is typically below 30 degrees Celsius. The water flow rate is adjusted according to the heat load demand, for example, 0.5-1.5 m / s. By utilizing low-temperature water as a heat transfer medium and extracting stored heat from the soil, energy transfer across time and on-demand supply are achieved, further improving the system's economy and flexibility.

[0039] Many embodiments and applications beyond the examples provided will be apparent to those skilled in the art upon reading the foregoing description. Therefore, the scope of this teaching should not be determined by reference to the foregoing description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

[0040] The above content provides a further detailed description of the present invention. It should not be construed that the specific embodiments of the present invention are limited to this. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the scope of protection of the present invention as defined by the submitted claims.

Claims

1. A geothermal energy storage system coupled with thermal power generation, characterized in that, It includes a steam turbine cylinder (1), a steam pipeline (2) and a first exhaust steam pipeline (3). The outlet of the steam pipeline (2) is connected to the steam inlet of the steam turbine cylinder (1), and the exhaust port of the steam turbine cylinder (1) is connected to the inlet of the first exhaust steam pipeline (3). The first exhaust steam pipeline (3) is horizontally connected to a second exhaust steam pipeline (10). A control valve (4) is installed on the first exhaust pipe (3), and the outlet of the first exhaust pipe (3) is connected to the inlet of the underground heating network (6) buried in the underground soil layer (5); The outlet of the underground heating network (6) is connected to the inlet of a one-way valve (9), and the outlet of the one-way valve (9) is connected to the second exhaust pipe (10).

2. The geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, The control valve (4) is an electric regulating valve or a pneumatic regulating valve.

3. A geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, The control valve (4) is located on the first exhaust pipe (3) and below the connection between the first exhaust pipe (3) and the second exhaust pipe (10).

4. A geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, The underground heating network (6) is buried at a depth of 50~300m.

5. A geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, The underground heating network (6) is one of U-shaped buried pipe, spiral coil pipe or multi-pass direct buried pipe.

6. A geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, The outlet of the second exhaust pipe (10) leads to the reheater or condenser.

7. A geothermal energy storage system coupled with thermal power generation according to claim 1, characterized in that, It also includes a geothermal well, a geothermal well inlet pipe (7) and a geothermal well outlet pipe (8); the geothermal well is vertically drilled in the underground soil layer (5) and is located within the heat influence radius of the underground heat pipe network (6).

8. A geothermal energy storage system coupled with thermal power generation according to claim 7, characterized in that, The geothermal well is provided with a wellhead, which has an inlet end and an outlet end; one end of the geothermal well inlet pipe (7) is connected to the inlet end of the geothermal well well, and one end of the geothermal well outlet pipe (8) is connected to the outlet end of the geothermal well well.

9. A geothermal energy storage method based on the system of any one of claims 1 to 8 coupled with thermal power generation, characterized in that, Includes the following steps: During normal operation of the thermal power unit, the control valve (4) is closed, and all the steam discharged from the turbine cylinder (1) flows into the second exhaust pipeline (10) through the first exhaust pipeline (3) and is delivered to the reheater or condenser. During the deep adjustment or rapid load reduction of the thermal power unit, the control valve (4) is in the open state. Part of the steam discharged from the turbine cylinder (1) flows directly into the second steam pipeline (10) through the first exhaust pipeline (3), and the other part is led out through the control valve (4) and input into the underground heat pipe network (6) buried in the underground soil layer (5). The steam flows within the underground heat pipe network (6), transferring its heat to the surrounding underground soil layers (5). Steam that has been heated by the underground heating network (6) flows out from its outlet and enters the second exhaust steam pipeline (10) through the one-way valve (9). The second steam line (10) delivers steam from the first steam line (3) and steam from the one-way valve (9) to the reheater or condenser.

10. A geothermal energy storage method coupled with thermal power generation according to claim 9, characterized in that, It also includes the following steps: After the underground heating network (6) has been running for a predetermined time, low-temperature water is introduced into the geothermal well inlet pipe (7) so that the low-temperature water enters the underground soil layer (5) through the geothermal well. Low-temperature water flows in the underground soil layer (5), absorbs heat from the surrounding environment and heats up, and is drawn out by the geothermal well outlet pipe (8).

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