Thermoelectric double-storage energy supply system

Abstract

The invention relates to a thermoelectric double-storage energy supply system. The thermoelectric double-storage energy supply system integrates a double-water-turbine design of a production well and a recharge well. The system intelligently responds to power grid electricity price fluctuation and heat supply requirements, and the working mode of the water turbine is flexibly adjusted. In the thermoelectric linkage optimization stage, when the electricity price is in a low ebb, the first water turbine extracts geothermal water to supply heat, and residual heat is stored in the heat and electricity storage water tank and the water storage tank to deal with the electricity price peak. And meanwhile, the second water turbine reversely generates power by utilizing geothermal tail water and feeds back to the power grid. In the energy storage and release optimization stage, the two water turbines work cooperatively in the electricity price off-peak period, and electric energy is converted into potential energy to be stored in the water tank. At the peak of electricity price, the high-position potential energy water in the water tank is released, and the stored potential energy is converted into electric energy through reverse operation of the water turbine to provide stable power supply for a power grid. According to the system, dual storage of heat and electricity is realized, the consumption contribution to distributed new energy photovoltaic wind power utilization is improved, the light and electricity abandoning quantity is reduced, and the distributed new energy power generation of a power grid and the electrical load of a building are balanced.

Description

Technical Field

[0001] The present invention relates to the technical field of geothermal energy utilization, and in particular to a thermoelectric dual storage and energy supply system. Background Art

[0002] There are some challenges in the use of geothermal energy. For example, during the peak heating period, the ground source heat pump system will produce geothermal tail water with residual pressure after extracting the heat energy from the geothermal water. When these tail waters are recharged into deeper groundwater layers (usually at a depth of 80 to 150 meters), the residual pressure and potential energy they carry are often not fully utilized, resulting in potential waste of resources.

[0003] CN110207409A discloses a deep-well geothermal power generation, heat storage and heating system and control method for power grid peak regulation, the system includes a medium-low temperature geothermal power generation device, the medium-low temperature geothermal power generation device is connected to a geothermal production well and a geothermal reinjection well through a geothermal production well pipeline and a geothermal reinjection well pipeline respectively, and the medium-low temperature geothermal power generation device is connected to the power grid through an online circuit. A production well heat exchanger is provided in the geothermal production well, and the production well heat exchanger is connected to a high-temperature heat pump through a heat pump production well side pipeline. A reinjection well heat exchanger is provided in the geothermal reinjection well, and the reinjection well heat exchanger is connected to a high-temperature heat pump through a heat pump reinjection well side pipeline. The reinjection well heat exchanger and the production well heat exchanger are U-tube or coaxial sleeve type closed heat exchangers. The high-temperature heat pump is provided with an external heating interface.

[0004] This patent utilizes excess electricity during periods of low power consumption, generates heat through high-temperature heat pumps and stores the heat in geothermal wells, and starts medium and low temperature geothermal power generation during peak power consumption periods to increase the power generation capacity of medium and low temperature geothermal power generation and increase the power supply capacity of the power grid during peak power consumption periods.

[0005] However, the disadvantage of this method is that it lacks the flexibility of year-round operation and the ability of diversified energy management. The technical solution of this patent is mainly aimed at seasonal grid peak load regulation and heating demand, and does not fully utilize the resources in the energy storage and energy release optimization stage, resulting in idle waste of resources in the entire system, resulting in the utilization rate and economic benefits of the system being inferior to the system that operates throughout the year. In addition, the technical solution of this patent does not fully consider the recovery and utilization of the residual pressure and potential energy of geothermal tail water. Therefore, the technical solution of this patent has limitations in the comprehensive utilization of energy throughout the year, the economic benefits of the system, and the environmental benefits.

[0006] In addition, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the applicant studied a large number of documents and patents when making the present invention, but due to space limitations, not all details and contents are listed in detail. However, this does not mean that the present invention does not have the characteristics of these prior arts. On the contrary, the present invention already has all the characteristics of the prior art, and the applicant reserves the right to add relevant prior art to the background technology. Summary of the invention

[0007] In view of the deficiencies of the prior art, the present invention provides a thermal and electric dual storage and energy supply system to solve at least part of the above-mentioned technical problems.

[0008] The present invention relates to a thermal power dual storage and energy supply system, comprising a first turbine configured in a production well and a second turbine configured in a recharge well. The system can adjust the operation mode of the first turbine and the second turbine according to the fluctuation of power grid electricity price, heating demand and new energy power generation and consumption demand, so as to switch the pumping function and power generation function of the two. In the thermal power linkage optimization stage, the first turbine runs forward to extract geothermal water in the production well, and the heat in the geothermal water can be stored in a dual-purpose water tank for heat storage and electricity storage and a water outlet tank, and the second turbine uses the potential energy of geothermal tail water converted from geothermal water that has completed heat exchange to run in reverse to generate electricity for the power grid; in the energy storage and release optimization stage, the first turbine and the second turbine run synchronously to convert electrical energy into potential energy and store it in the dual-purpose water tank for heat storage and electricity storage and a water storage tank, or use the high potential energy water stored in the dual-purpose water tank for heat storage and electricity storage and a water storage tank to reversely generate electricity to supply the power grid. Compared with the prior art, the beneficial effects of the present invention are:

[0009] First, when the traditional geothermal system is providing heat, the residual pressure of the geothermal tail water and the potential energy between the ground and the reinjection liquid level of the geothermal reinjection well are released due to the free fall of the geothermal water, resulting in the waste of the available residual pressure and potential energy of the geothermal tail water. Recovering this part of the mechanical energy of the geothermal tail water and generating electricity can greatly reduce the power consumption of the geothermal system and improve the efficiency of the geothermal system.

[0010] Secondly, peak-valley electricity prices are common across the country. The energy used by geothermal heating systems is electricity. By utilizing the peak-valley electricity price policy of the power grid to configure a peak-shaving and valley-filling heat storage system, heat storage can be performed during the valley electricity price period, and heat release and heating can be performed during the peak electricity period. This can reduce electricity consumption during the peak electricity period and increase electricity consumption during the valley electricity period. This can greatly reduce the configuration capacity of the geothermal heating system, reduce the energy consumption cost of the geothermal system, and improve the economic benefits of the geothermal heating system.

[0011] Thirdly, the traditional geothermal heating system is only used in the winter heating season. During the energy storage and release optimization stage, the entire system is in an idle state of shutdown, resulting in idle waste of the entire system resources. By utilizing the low-level groundwater resources of the deep geothermal system, the dual-purpose water turbine equipment for pumping power generation, and the ground water storage tank equipment of the geothermal system, during the low-peak electricity price period of the energy storage and release optimization stage, the dual-purpose water turbine for pumping power generation is used to extract deep low-level groundwater to the ground dual-purpose water tank for heat storage and electricity storage to realize the electricity storage function. During the peak electricity price period, the geothermal water in the ground dual-purpose water tank for heat storage and electricity storage is released into the geothermal well. At the same time, the falling geothermal water flushes the dual-purpose water turbine for pumping power generation to realize power generation operation, realizing the power storage or power generation operation mode, improving the annual utilization efficiency of geothermal system assets, improving the economic value of the geothermal system, realizing the dual storage mode of heat and electricity, and improving the local green electricity consumption capacity.

[0012] According to a preferred embodiment, the system includes a geothermal direct supply heat exchanger and a geothermal tail water heat exchanger, which are connected in series with the first turbine and the second turbine through a geothermal water pipeline. The first turbine is connected to the input end of the geothermal direct supply heat exchanger through the geothermal water pipeline. After the geothermal direct supply heat exchanger performs heat exchange, the cooled geothermal water is sent to the geothermal tail water heat exchanger through the geothermal water pipeline. After the geothermal tail water heat exchanger further recovers heat, the geothermal tail water uses high potential energy to drive the second turbine to rotate, thereby generating electricity and being incorporated into the power grid. This scheme adopts a two-stage heat exchange system of geothermal direct supply heat exchanger and geothermal tail water heat exchanger, which effectively improves the heat utilization rate of geothermal water. The geothermal direct supply heat exchanger first performs preliminary heat exchange to provide heat energy for external systems (such as heating, hot water supply, etc.), and then the geothermal tail water heat exchanger further recovers the remaining heat, reducing the waste of geothermal energy.

[0013] According to a preferred embodiment, the dual-use water tank for heat storage and electricity storage is connected to the geothermal direct heat exchanger through the first heat exchange pipeline. A heat storage water pump is installed on the first heat exchange pipeline. The inlet of the pump is directly connected to the outlet of the dual-use water tank for heat storage and electricity storage, and its outlet is connected to the inlet of the geothermal direct heat exchanger. The geothermal water enters the geothermal direct heat exchanger through the geothermal water pipeline, where it exchanges heat with the first circulating warm water and forms a cooling water. The first circulating warm water in the first heat exchange pipeline absorbs heat and is converted into the first circulating hot water. The heat storage water pump drives the first circulating hot water to circulate along the first heat exchange pipeline and transports the heat to the dual-use water tank for heat storage and electricity storage for storage. As an energy storage unit, the dual-use water tank for heat storage and electricity storage can play a buffering role when the geothermal direct heat exchanger generates thermal energy fluctuations, ensuring that the heat or electrical energy output by the system is relatively stable. This is particularly important for occasions that require a stable energy supply, such as heating, industrial production, etc.

[0014] According to a preferred embodiment, the geothermal tail water heat exchanger is connected to the water source heat pump through an internal heat exchange pipeline. The water source heat pump includes an evaporator and a condenser connected to each other through a heat exchange process. The evaporator is connected to the geothermal tail water heat exchanger through the internal heat exchange pipeline, and the condenser is connected to the heat storage and electricity storage dual-purpose water tank through the first heat exchange pipeline. An intermediate water pump is arranged on the internal heat exchange pipeline to provide a driving force for the flow of the internal circulation water. The internal circulation cold water starts from the outlet of the evaporator and enters the inlet of the geothermal tail water heat exchanger through the internal heat exchange pipeline. The other inlet of the geothermal tail water heat exchanger introduces primary cooling water, wherein the primary cooling water releases heat in the geothermal tail water heat exchanger to be converted into geothermal tail water, and the internal circulation cold water absorbs heat to be converted into internal circulation warm water. By combining the geothermal tail water heat exchanger with the water source heat pump, the scheme realizes the efficient recovery of the residual heat in the geothermal tail water. The geothermal tail water releases its residual heat in the geothermal tail water heat exchanger, and the heat is absorbed by the internal circulation cold water, thereby being converted into internal circulation warm water. This process not only reduces the heat energy waste of geothermal tail water, but also improves the heat energy recovery efficiency of the entire system.

[0015] According to a preferred embodiment, the first heat exchange pipeline is designed as a double-branch structure, one end of which is connected to the outlet of the hot water storage pump, and the other end is respectively connected to the condenser and the geothermal direct heat exchanger. The first circulating warm water circulating in the first heat exchange pipeline flows out from the heat storage and electricity storage dual-purpose water tank, enters the condenser and exchanges heat with the internal circulating warm water to heat up to the first circulating hot water. The first circulating hot water after heat exchange returns to the heat storage and electricity storage dual-purpose water tank for storage through one branch of the first heat exchange pipeline, and the other branch is used to directly send the first circulating hot water to the geothermal direct heat exchanger for heat exchange with the geothermal water. The first heat exchange pipeline adopts a double-branch design, so that the first circulating hot water can choose two different paths for transmission after heating. On the one hand, part of the first circulating hot water can be returned to the heat storage and electricity storage dual-purpose water tank for storage for subsequent use; on the other hand, another part of the first circulating hot water can be directly sent to the geothermal direct heat exchanger to exchange heat with the geothermal water, further improving the utilization efficiency of thermal energy.

[0016] According to a preferred embodiment, the system is equipped with a heat-releasing heat exchanger connected to a heat storage and electricity storage dual-purpose water tank through a first heat exchange pipeline, and a heat-releasing water pump is arranged on the first heat exchange pipeline to drive the circulating water flow in the heat exchange pipeline to ensure that the first circulating water exchanges heat in the heat-releasing heat exchanger, and the heat-releasing heat exchanger is connected to the heating user through a second heat exchange pipeline, and a heat-supply water pump is arranged on the second heat exchange pipeline to drive the second circulating water flow in the pipe. The heat-releasing heat exchanger is connected to the heating user through the second heat exchange pipeline, and a heat-supply water pump is arranged to drive the second circulating water flow. This technical solution can flexibly adjust the heating amount according to the needs of the heating user. The heat-supply water pump can adjust the flow rate according to the change of the heating load, so as to achieve precise control of the heating temperature and meet the heating needs of different users.

[0017] According to a preferred embodiment, the dual-use water tank for heat storage and electricity storage is connected to the production well and the recharge well through a water circulation pipeline, and the water storage tank is connected to the production well and the recharge well through a first water supply pipeline and a second water supply pipeline connected to the geothermal water pipeline. The water turbine in the well can extract geothermal water from the production well and / or the recharge well, and transport it to the dual-use water tank for heat storage and electricity storage through the water circulation pipeline for storage, and / or transport it to the water storage tank through the first water supply pipeline and the second water supply pipeline for storage, thereby converting electrical energy into the high potential energy of water. The dual-use water tank for heat storage and electricity storage and / or the water storage tank can release the stored geothermal water back to the production well and / or the recharge well according to system requirements, so as to convert the high potential energy back to electrical energy by driving the two turbines to rotate in the opposite direction. This solution converts electrical energy into the high potential energy of water for storage, rather than the traditional battery energy storage or mechanical energy storage method. This conversion method utilizes the natural flow and storage characteristics of geothermal water. The geothermal water is extracted from production wells or reinjection wells and transported to high locations through water circulation pipelines, thereby achieving indirect storage of electrical energy.

[0018] According to a preferred embodiment, the system is configured with a plurality of valves for controlling fluid flow, wherein the first valve and the eighth valve are located on the first heat exchange pipeline on one side of the heat storage and power storage water tank, and the second valve and the ninth valve are located on the first heat exchange pipeline on the other side of the heat storage and power storage water tank, the geothermal water pipeline is respectively configured with a fifth valve and a seventh valve near the production well and the reinjection well to control the well water return process, on the water circulation pipeline, the third valve is configured near the heat storage and power storage water tank, and the fourth valve and the sixth valve are arranged near the two water wells, the first water supply pipeline is configured with a first water supply valve for controlling the on and off of geothermal water drawn from the production well by the first turbine; the second water supply pipeline is configured with a second water supply valve for controlling the on and off of geothermal tail water obtained by heat exchange from the geothermal tail water heat exchanger or for controlling the on and off of geothermal water drawn from the reinjection well by the second turbine; the water discharge pipeline is configured with a water discharge valve for controlling the flow of high potential energy water in the water storage tank to the geothermal water pipeline. By precisely controlling the opening and closing status and opening size of each valve, this technical solution can optimize the system's fluid flow path and flow distribution, reducing unnecessary energy loss and fluid waste. This helps improve the system's overall operating efficiency, reduce operating costs, and extend the system's service life.

[0019] According to a preferred embodiment, in the heat-electric linkage optimization stage, the system can switch between three operating modes, namely, heat supply and power generation, heat supply and heat storage power generation, and heat release and heat supply, according to the heating demand and electricity price period. In the period when the heating demand is large and the electricity price is high, the system switches to the heat supply and power generation operation mode to give priority to meeting the heating demand, and generates electricity through the second turbine to achieve cogeneration of heat and power; in the period when the heating demand is small and the electricity price is low, while meeting the heating demand, the system switches to the heat supply and heat storage power generation operation mode to store excess heat in the heat storage and electricity dual-use water tank, and uses the second turbine to generate electricity; in the period of peak electricity price, the system switches to the heat release and heating operation mode to use the heat stored in the heat storage and electricity dual-use water tank for heating to reduce the operating cost. This technical solution reduces the dependence on fossil fuels and greenhouse gas emissions by efficiently utilizing energy and reducing operating costs, and is in line with the concept of environmental protection and sustainable development. Through intelligent management and optimized operation strategies, the system can maximize the utilization of energy and minimize waste while meeting the heating demand.

[0020] According to a preferred embodiment, in the energy storage and release optimization stage, the system switches between the power storage operation mode and the power generation operation mode according to the peak and valley periods of electricity prices, wherein the system utilizes the valley electricity price period to pump groundwater into the heat storage and power storage dual-purpose water tank to store high potential energy through the first turbine and / or the second turbine to realize the power storage operation mode; the system utilizes the peak electricity price period to release the high potential water to the production well and / or the recharge well, and reversely generates electricity through the first turbine and / or the second turbine to realize the power generation operation mode. This technical solution utilizes the heat storage and power storage dual-purpose water tank as the energy storage medium, and realizes the indirect storage of electric energy by storing the high potential energy of water. This storage method has a high energy density and a long storage period, and can meet the demand for energy storage during the energy storage and release optimization stage. At the same time, as an energy conversion device, the turbine can maintain a high conversion efficiency during both the pumping energy storage and the water discharge power generation process, reducing the energy loss during the conversion process. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a simplified schematic diagram of the module connection relationship of the thermoelectric dual storage and energy supply system provided by the present invention;

[0022] Figure 2 It is a simplified schematic diagram of module connection relationship when the thermoelectric dual storage and energy supply system provided by the present invention is in a heat and power generation operation mode at the thermoelectric linkage optimization stage;

[0023] Figure 3 It is a simplified schematic diagram of module connection relationship when the heat-electric dual storage and energy supply system provided by the present invention is in the heat-electricity linkage optimization stage heat supply and heat storage and power generation operation mode;

[0024] Figure 4 It is a simplified schematic diagram of module connection relationship when the thermoelectric dual storage and energy supply system provided by the present invention is in the heat release and heating operation mode in the thermoelectric linkage optimization stage;

[0025] Figure 5 It is a simplified schematic diagram of module connection relationship when the thermoelectric dual energy storage and supply system provided by the present invention is in the energy storage and energy release optimization stage and the energy storage operation mode;

[0026] Figure 6 It is a simplified schematic diagram of module connection relationship when the thermoelectric dual storage and supply system provided by the present invention is in the power generation operation mode of the energy storage and release optimization stage;

[0027] Figure 7 It is a schematic diagram of hourly solar radiation illumination;

[0028] Figure 8 This is a schematic diagram of solar power generation hour by hour.

[0029] Reference numerals list

[0030] 100: First turbine; 110: Evaporator; 120: Geothermal direct heat exchanger; 130: Geothermal tail water heat exchanger; 140: Intermediary water pump; 150: Water source heat pump; 160: Thermal storage and electricity storage dual-use water tank; 170: Hot water storage pump; 180: Discharging hot water pump; 190: Discharging heat exchanger; 200: Hot water supply pump; 210: Heating user; 220: Second turbine; 231: First valve; 232: Second valve; 233: Third valve; 234: Fourth valve; 235: Fifth valve; 236: The sixth valve; 237: the seventh valve; 238: the eighth valve; 239: the ninth valve; 240: the condenser; 250: the production well; 260: the reinjection well; 270: the geothermal water pipeline; 280: the first heat exchange pipeline; 290: the internal heat exchange pipeline; 300: the second heat exchange pipeline; 310: the water circulation pipeline; 400: the water storage tank; 410: the first water supply pipeline; 411: the first water supply valve; 420: the second water supply pipeline; 421: the second water supply valve; 430: the drain pipeline; 431: the drain valve. DETAILED DESCRIPTION

[0031] The following is a detailed description with reference to the accompanying drawings.

[0032] Example 1

[0033] The present invention proposes an integrated thermal power dual storage and energy supply system, which can achieve efficient utilization of geothermal energy and energy storage through a variety of operating modes. Figure 1As shown, it includes two turbines, which are preferably high-efficiency equipment for both pumping and power generation. The equipment can rotate forward under the drive of electric energy to extract geothermal water in the well, and can also rotate backward to generate electricity using the kinetic energy and potential energy in the water. Specifically, the first turbine 100 is responsible for extracting geothermal water rich in thermal energy from a special production well 250. This process not only realizes the initial extraction of geothermal resources, but also lays the foundation for subsequent energy conversion; the second turbine 220 utilizes the high potential energy naturally formed by geothermal tail water during the process of reinjection into the reinjection well 260, and realizes secondary conversion and recovery of energy through the principle of hydroelectric power generation, which significantly improves the overall energy utilization efficiency of the system.

[0034] Preferably, if Figure 1As shown, in the system of the present invention, the first turbine 100, the geothermal direct heat exchanger 120, the geothermal tail water heat exchanger 130 and the second turbine 220 are connected in series in sequence through the geothermal water pipe 270. The geothermal direct heat exchanger 120 is used to directly transfer the heat of the geothermal water to the heating system to provide heat energy for the heating user 210. Specifically, the output end of the first turbine 100 is connected to the input end of the geothermal direct heat exchanger 120 through the high-pressure geothermal water pipe 270 to ensure that the geothermal water can effectively transfer the heat energy to the heating medium when flowing through the heat exchanger, thereby providing the required heat energy for the heating system. The geothermal direct heat exchanger 120 is designed to maximize the heat exchange efficiency to reduce the loss of heat energy. After the heat exchange of the geothermal direct heat exchanger 120, the temperature of the geothermal water drops. This part of the geothermal water after cooling is called the primary cooling water, which is transported to the geothermal tail water heat exchanger 130 through another section of the geothermal water pipe 270. In the geothermal tail water heat exchanger 130, the primary cooling water and the heating return water undergo secondary heat exchange. This process is intended to recover the remaining heat in the geothermal water, provide additional heat energy for the heating system, and further reduce the temperature of the geothermal water. After completing the secondary heat exchange, the geothermal water is used as geothermal tail water, and a part of it is transported to the second turbine 220 through the geothermal water pipeline 270. At this stage, the geothermal tail water uses its remaining high potential energy to drive the second turbine 220, converting mechanical energy into electrical energy, and providing renewable energy for the power grid; another part of the geothermal tail water can pass through the second water supply pipeline 420, one end of which is connected to a branch interface of the geothermal water pipeline 270, and the other end is injected into the water storage tank 400 from the top. As a high potential energy storage standby water tank, the water storage tank 400 can transport the geothermal tail water stored inside to another branch interface of the geothermal water pipeline 270 through the water discharge pipeline 430 connected to its bottom at an appropriate time. Subsequently, the geothermal tail water flows along the geothermal water pipeline 270 and finally reaches the second turbine 220 for energy conversion. The design of the second turbine 220 takes into account the characteristics of the geothermal tail water to optimize the power generation efficiency and reduce the loss during the energy conversion process. The design of the entire pipeline system is aimed at achieving efficient utilization of geothermal water resources, improving the comprehensive utilization efficiency of geothermal energy through cascade utilization and heat recovery technology, and ensuring the economy and sustainability of the system.

[0035] Preferably, if Figure 1As shown, in the geothermal heat and electricity dual storage energy supply system of the present invention, the integration of the heat storage and electricity dual water tank 160 is an integral part, which is interconnected with the geothermal direct supply heat exchanger 120 through the first heat exchange pipeline 280. Specifically, a hot water storage pump 170 is installed on the first heat exchange pipeline 280, and the inlet of the pump is directly connected to the outlet of the heat storage and electricity dual water tank 160, and its outlet is connected to the inlet of the geothermal direct supply heat exchanger 120. This configuration allows a heat cycle to be formed between the geothermal direct supply heat exchanger 120 and the heat storage and electricity dual water tank 160. The geothermal water enters the geothermal direct supply heat exchanger 120 through the geothermal hot water pipeline 270, where it exchanges heat with the first circulating warm water. In this process, the geothermal water releases heat, causing its temperature to drop, forming a cooling water. At the same time, the first circulating warm water absorbs heat, the temperature rises, and is converted into the first circulating hot water. The hot water storage pump 170 drives the first circulating hot water to circulate along the first heat exchange pipeline 280, and finally transfers the heat to the heat and electricity storage dual-purpose water tank 160 for storage.

[0036] Preferably, if Figure 1 As shown, in the geothermal heat and electricity dual storage and energy supply system of the present invention, the geothermal tail water heat exchanger 130 is connected to the water source heat pump 150 through the internal heat exchange pipeline 290 to achieve effective heat exchange. The water source heat pump 150 includes an evaporator 110 and a condenser 240, which are interconnected through a heat exchange process, wherein the evaporator 110 is connected to the geothermal tail water heat exchanger 130 through the internal heat exchange pipeline 290, and the condenser 240 is connected to the heat storage and electricity dual-use water tank 160 through the first heat exchange pipeline 280. An intermediate water pump 140 is configured on the internal heat exchange pipeline 290 to provide a driving force for the internal circulation water flow between the water source heat pump 150 and the geothermal tail water heat exchanger 130, ensuring the continuity and efficiency of the heat exchange process. The internal circulation water includes internal circulation cold water and internal circulation warm water. The internal circulation cold water starts from the outlet of the evaporator 110 and enters the inlet of the geothermal tail water heat exchanger 130 through the internal heat exchange pipeline 290. At the same time, the other inlet of the geothermal tail water heat exchanger 130 introduces primary cooling water to exchange heat with the internal circulation cold water. In the geothermal tail water heat exchanger 130, the primary cooling water further reduces the temperature through heat exchange with the internal circulation cold water to form geothermal tail water with a lower temperature. After the internal circulation cold water absorbs heat, the temperature rises and turns into internal circulation warm water.

[0037] After the geothermal water flows through the geothermal direct supply heat exchanger 120, its temperature usually drops to 30-35°C. Water in this temperature range is not suitable for direct use in the heating system inside the building, because heating usually requires the water supply temperature to reach above 35°C. Nevertheless, the primary cooling water at 30-35°C still contains considerable low-grade thermal energy, and the conversion efficiency of this part of energy is relatively low, but it can be effectively recovered and utilized through the water source heat pump 150.

[0038] The water source heat pump 150 is a highly efficient energy recovery device. The evaporator 110, condenser 240, compressor and other components it contains can extract heat from the low-temperature primary cooling water and raise it to 40°C or higher, so that it can meet the heating needs of the building. In this way, the water source heat pump 150 not only improves the energy utilization efficiency of geothermal water, but also expands the application scope of geothermal energy, realizes the full utilization of low-grade thermal energy, and thus optimizes the energy efficiency and economy of the entire heating system.

[0039] Preferably, if Figure 1 As shown, in the geothermal heat and electricity dual storage and energy supply system of the present invention, the first heat exchange pipeline 280 is designed to have at least two branches, so that the outlet of the hot water storage pump 170 can be connected to the condenser 240 and the geothermal direct supply heat exchanger 120 respectively. The hot water storage pump 170 is responsible for driving the first circulating water to flow in the pipeline to achieve heat exchange with the internal circulating water. The first circulating water includes the first circulating warm water and the first circulating hot water, the latter of which is obtained by the temperature increase of the first circulating warm water during the heat exchange process in the condenser 240. The first circulating warm water flows out from the heat storage and electricity dual water tank 160, and a part of it enters the condenser 240 under the promotion of the hot water storage pump 170, and exchanges heat with the internal circulating warm water driven by the intermediate water pump 140; the other part enters the geothermal direct supply heat exchanger 120, and exchanges heat with the geothermal water flow from the production well 250. Specifically, in the condenser 240, the first circulating warm water absorbs heat and heats up to form the first circulating hot water, while the internal circulating warm water releases heat, the temperature drops, and is converted into internal circulating cold water. Subsequently, the first heat exchange pipeline 280 transports the first circulating hot water that has undergone heat exchange in the condenser 240 back to the heat storage and electricity storage dual-purpose water tank 160 for storage, thereby completing the heat exchange and storage process. In the geothermal direct heat exchanger 120, the geothermal water that enters the geothermal direct heat exchanger 120 through the geothermal water pipeline 270 will exchange heat with the first circulating warm water. In this process, the geothermal water releases heat, causing its temperature to drop, forming a cooling water. At the same time, the first circulating warm water absorbs heat, the temperature rises, and is converted into the first circulating hot water. Through the aforementioned configuration, the system of the present invention can achieve efficient heat exchange between geothermal water and internal circulating water, between geothermal water and first circulating water, and between internal circulating water and first circulating water, and at the same time store the released heat in the heat storage and electricity storage dual-purpose water tank 160 for subsequent use, thereby improving energy utilization efficiency and enhancing the economy and sustainability of the system.

[0040] Preferably, the first circulation warm water driven by the hot water storage pump 170 can circulate heat in the geothermal direct heat exchanger 120 and the condenser 240 at the same time. In order to achieve a reasonable distribution of flow, flow sensors are configured at the outlet of the hot water storage pump 170 and the inlet of the geothermal direct heat exchanger 120 and the condenser 240. The main function of these sensors is to monitor the flow of the first circulation warm water in real time, and dynamically adjust the distribution of water flow according to the actual heat exchange requirements of the geothermal direct heat exchanger 120 and the condenser 240. The geothermal direct heat exchanger 120 and the condenser 240 can be data-connected to the flow sensor so that the two can feedback their respective heat exchange requirements and real-time heat exchange data to the flow sensor through wireless signal transmission. Based on these feedback information, the flow sensor can accurately determine the requirements of each heat exchanger. The flow control valve is linked to the flow sensor and can automatically adjust the opening according to the received heat exchange requirements. When the flow sensor detects a change in demand for a certain heat exchanger, the flow control valve will quickly change the water flow rate to ensure that the first cycle of warm water is reasonably distributed to the geothermal direct supply heat exchanger 120 and the condenser 240.

[0041] Preferably, if Figure 1 As shown, in the geothermal heat and electricity dual storage energy supply system of the present invention, a heat release heat exchanger 190 is also configured, which is connected to the heat storage and electricity dual-use water tank 160 through the first heat exchange pipeline 280 to achieve effective heat transmission. A heat release water pump 180 is configured on the first heat exchange pipeline 280, which is responsible for driving the circulating water in the heat exchange pipeline to ensure that the first circulating water exchanges heat in the heat release heat exchanger 190. The heat release heat exchanger 190 is also connected to the heating user 210 through the second heat exchange pipeline 300, and a hot water pump 200 is configured on the second heat exchange pipeline 300 to drive the second circulating water in the pipe to flow. The second circulating water is composed of the second circulating cold water and the second circulating warm water, wherein the second circulating warm water is obtained by the heat exchange process in the heat release heat exchanger 190, and the temperature rises after the second circulating cold water absorbs heat. The function of the heat release heat exchanger 190 is to exchange heat between the first circulating hot water in the first heat exchange pipeline 280 from the heat storage and electricity storage dual-use water tank 160 or the geothermal direct supply heat exchanger 120 and the condenser 240 and the second circulating cold water in the second heat exchange pipeline 300. In this process, the first circulating hot water releases heat, the temperature drops, and it is converted into the first circulating warm water; while the second circulating cold water absorbs heat, the temperature rises, and it is converted into the second circulating warm water. Subsequently, the hot water pump 200 delivers the second circulating warm water after heat exchange to the heating user 210 to meet its heating needs.

[0042] Preferably, if Figure 1As shown, in the geothermal thermal power dual storage energy supply system of the present invention, the heat storage and electricity storage dual water tank 160 is connected to the production well 250 and the recharge well 260 through a dedicated water circulation pipeline 310, so as to realize the effective management and energy conversion of geothermal water. The system utilizes the dual-purpose function of the water turbine in the well to extract the geothermal water in the production well 250, and transports it to the heat storage and electricity storage dual water tank 160 through the water circulation pipeline 310 for storage. In this process, the electrical energy is converted into the high potential energy of water, realizing the initial storage of energy. The heat storage and electricity storage dual water tank 160 can not only store geothermal water, but also release the stored water back to the production well 250 or the recharge well 260 according to the system demand or during the low electricity price period. This operation converts the high potential energy back to electrical energy by driving at least one of the two turbines to rotate in the opposite direction, thereby realizing the reuse of energy. This two-way energy conversion mechanism not only improves the energy utilization efficiency of the system, but also provides a flexible peak-shaving resource for the power grid. In addition, the control strategy of the system can intelligently dispatch the water circulation between the heat and electricity storage dual-use water tank 160 and the water well, as well as the operation mode of the turbine according to the grid demand, electricity price signal and thermal energy demand. This intelligent dispatching mechanism ensures that the system can meet the heating demand while optimizing electricity production, improving the economy and environmental friendliness of the entire system.

[0043] Preferably, if Figure 2As shown, in the geothermal heat and electricity dual storage and energy supply system of the present invention, the pipeline system realizes precise control of fluid flow through a number of finely configured valves, ensuring that the system can flexibly switch between different working modes to adapt to the diverse needs of system operation. Specifically, on the first heat exchange pipeline 280, the first valve 231 and the eighth valve 238 are located at the top entrance and exit of the heat storage and electricity storage dual water tank 160, wherein the first valve 231 controls the on-off of the first circulating hot water flowing from the geothermal direct supply heat exchanger 120 and / or the condenser 240 to the heat storage and electricity storage dual water tank 160, and the eighth valve 238 controls the on-off of the first circulating hot water flowing through the first valve 231 or out of the heat storage and electricity storage dual water tank 160. The second valve 232 and the ninth valve 239 are located at the bottom entrance and exit of the heat storage and electricity storage water tank 160, wherein the second valve 232 controls the on-off of the first circulating warm water from the heat storage and electricity storage water tank 160 to the condenser 240 and / or the geothermal direct heat exchanger 120 through the first heat exchange pipeline 280, and the ninth valve 239 controls the first circulating warm water from the heat release heat exchanger 190 to flow into the heat storage and electricity storage water tank 160 and / or flow to the second valve 232. Such a configuration allows the system to adjust the fluid flow in the first heat exchange pipeline 280 according to the heat exchange requirements and optimize the transfer efficiency of thermal energy. The geothermal water pipeline 270 is located near the production well 250 and the reinjection well 260, and a bypass pipe with the end opening facing the well is set at the wellhead of the two wells in a branching manner. The bypass pipes of the production well 250 and the reinjection well 260 are respectively provided with the fifth valve 235 and the seventh valve 237 for the well water recovery process. Their main function is to discharge the blockages that may have accumulated in the well at the wellhead within a period of time after the water pump in the well is turned on, so as to ensure the smooth flow of water. The water circulation pipeline 310 is equipped with a third valve 233, a fourth valve 234 and a sixth valve 236, so that through the coordinated work of these valves, the flow direction of the fluid in the water circulation pipeline 310 can be controlled to achieve turbine power generation or high potential energy storage. Specifically, the third valve 233 is arranged near the heat storage and electricity storage water tank 160, which is used to control the flow of geothermal water between the geothermal water from the production well 250 and / or the recharge well 260 and the heat storage and electricity storage water tank 160, while the fourth valve 234 and the sixth valve 236 are arranged near the two water wells, respectively controlling the flow of geothermal water between each water well and the heat storage and electricity storage water tank 160. In addition, in order to enable the water tank 400 to be replenished and drained at the appropriate time, the first water replenishment pipe 410 and the second water replenishment pipe 420 connected to the top of the water tank 400 are respectively provided with a first water replenishment valve 411 and a second water replenishment valve 421 that can be controlled to open and close, while the drain pipe 430 connected to the bottom of the water tank 400 is provided with a drain valve 431 that can be controlled to open and close.The first water replenishment valve 411 is used to control the on-off of geothermal water pumped from the production well 250 by the first water turbine 100, that is, the first water replenishment valve 411 can provide the water storage tank 400 with a water replenishment path directly from the production well 250. The second water replenishment valve 421 has two different water replenishment paths according to the different operation modes of the system. Specifically, when the geothermal tail water heat exchanger 130 is running and produces geothermal tail water, the second water replenishment valve 421 is used to control the on-off of geothermal tail water flowing from the second water replenishment pipeline 420 to the water storage tank 400; when the second water turbine 220 pumps out geothermal water from the recharging well 260, the second water replenishment valve 421 is used to control the on-off of geothermal water flowing from the second water replenishment pipeline 420 to the water storage tank 400. The water release valve 431 is used to control the outflow of high potential water in the water storage tank 400 to the geothermal water pipeline 270.

[0044] Preferably, the geothermal heat and electricity dual storage energy supply system of the present invention can reasonably switch between multiple working modes according to the demand for heat load of the heating user 210 and the tiered electricity price of the time period. Specifically, the working mode of the system is divided into two stages: the heat and power linkage optimization stage and the energy storage and release optimization stage. In the heat and power linkage optimization stage, the system exchanges heat through the geothermal direct supply heat exchanger 120 and the geothermal tail water heat exchanger 130 to provide heat energy for the heating user 210. At the same time, the residual pressure and potential energy of the geothermal tail water are recovered by the dual-use water turbine for pumping and power generation to generate electricity. According to the heating demand and the electricity price period, the system can switch between three operating modes: heat supply and power generation, heat supply and heat storage and power generation, and heat release and heating. In the energy storage and release optimization stage, the system uses the off-peak electricity price period to pump groundwater into the dual-use water tank 160 for heat storage and electricity storage and the water tank 400 through the dual-use water turbine for pumping and power generation to store high potential energy, thereby realizing the power storage operation mode. During the peak electricity price period, the system releases high potential water into the geothermal well, and generates electricity in reverse through the dual-purpose water turbine for pumping and power generation, thus realizing the power generation operation mode. The main function of the water tank 400 is to store water with higher potential energy. It is mainly responsible for water storage in the system, rather than participating in the heat exchange cycle process. Therefore, the design of the water tank 400 does not need to use insulation materials, which can effectively reduce material costs and construction difficulties, thereby reducing the cost of the entire system.

[0045] Preferably, the geothermal heat and electricity dual storage and energy supply system of the present invention can optimize and switch between multiple working modes according to the demand of the heating user 210 for heat load and the change of electricity price period through intelligent control strategy, so as to achieve efficient utilization of energy and maximize cost-effectiveness. The working mode of the system is mainly divided into two stages: the heat and power linkage optimization stage and the energy storage and release optimization stage. Each stage is specially designed for specific energy needs and market conditions.

[0046] During the optimization stage of heat-electric linkage, the system mainly exchanges heat through the geothermal direct supply heat exchanger 120 and the geothermal tail water heat exchanger 130 to meet the thermal energy demand of the heating user 210. The geothermal direct supply heat exchanger 120 is responsible for directly transferring the thermal energy of the geothermal water to the heating system, while the geothermal tail water heat exchanger 130 further recovers the residual thermal energy of the geothermal water after the initial heat exchange to improve the energy efficiency of the entire system. In addition, the system also uses a dual-use water turbine for pumping and power generation to recover the residual pressure and potential energy of the geothermal tail water for power generation, thereby achieving dual output of heat and electricity. Depending on the heating demand and electricity price period, the system can switch between the following three operating modes:

[0047] 1. Heating and power generation operation mode: During periods of high heating demand and high electricity prices, the system gives priority to meeting heating demand and generates electricity through a dual-purpose water turbine for pumped power generation to achieve cogeneration of heat and power.

[0048] 2. Heating and heat storage power generation operation mode: During periods of low heating demand and low electricity prices, the system stores excess heat in the heat storage and electricity storage dual-purpose water tank 160 while meeting the heating demand, and uses the pumped-water dual-purpose water turbine to generate electricity.

[0049] 3. Heat release heating operation mode: When the heat demand is small and it is during the peak electricity price and peak power price period, the system uses the heat stored in the heat storage and electricity storage dual-purpose water tank 160 for heating to reduce the operating cost.

[0050] In the energy storage and release optimization stage, the system mainly focuses on the storage and generation of electric energy. In the period of low electricity price or when photovoltaic power generation cannot be connected to the grid, the system uses the dual-purpose water turbine for pumping water to pump groundwater into the dual-purpose water tank 160 for heat storage and electricity storage, converts electric energy into high potential energy for storage, and realizes the power storage operation mode. In the period of high electricity price, the system releases the high potential water into the geothermal well, and reversely generates electricity through the dual-purpose water turbine for pumping water to realize the power generation operation mode, providing peak power support for the power grid.

[0051] Through this flexible working mode switching, the geothermal and thermal power dual storage and energy supply system of the present invention can achieve efficient energy utilization and economic optimization according to actual energy demand and market conditions, while improving the adaptability and reliability of the system.

[0052] The following describes the five working modes of the geothermal thermal power dual storage energy supply system from the two stages of thermal power linkage optimization and energy storage release optimization:

[0053] 1. Heat and power optimization stage

[0054] 1. Heating and power generation operation mode

[0055] Preferably, if Figure 2As shown, when the heating load is large in the thermal power linkage optimization stage and the heat in the dual-purpose water tank 160 for heat storage and electricity storage has been completely stored, the system's heating supply is equal to the user's demand. At this time, the system is configured in the heating and power generation operation mode, and all the heat of the geothermal heating system is supplied to the heating user 210. While supplying heat, the dual-purpose water turbine for pumping and power generation in the geothermal recharge well 260 is used to recover the residual pressure and tail water potential energy of the geothermal tail water for power generation. While supplying heat, the system uses its own resources to generate electricity, thereby reducing the electricity consumption of the geothermal system and improving the geothermal efficiency.

[0056] Specifically, the geothermal water is first extracted from the production well 250 by the first turbine 100 and flows directly into the geothermal direct supply heat exchanger 120. Here, the geothermal water releases its heat energy to the heating system, and at the same time, its own temperature drops to form a cooling water. Subsequently, this part of the cooling water continues to flow to the geothermal tail water heat exchanger 130, where it exchanges heat with the evaporator 110 of the water source heat pump 150, further reducing the temperature and providing the necessary heat energy for the water source heat pump 150. After absorbing the heat in the geothermal tail water, the water source heat pump 150 releases hot water through its condenser 240. The hot water is transported to the heat release heat exchanger 190 through the heat release water pump 180 according to the heating demand, thereby exchanging heat with the return water of the heating user 210 to meet the user's heating needs. After the geothermal water completes the heat release, part of the geothermal tail water it is converted into flows into the recharge well 260, and the other part is stored in the water storage tank 400. The high potential energy water stored in the water tank 400 will be poured into the recharge well 260 when the peak electricity price is reached, so as to generate electricity by utilizing the high potential energy again. In the recharge well 260, the second turbine 220 generates electricity by utilizing the high potential energy and residual pressure of the geothermal tail water, converting mechanical energy into electrical energy, and providing renewable energy for the power grid. This process not only realizes the thermal energy utilization of geothermal water, but also improves the energy utilization efficiency of the system by recovering the residual pressure and potential energy of the geothermal tail water.

[0057] In the heating and power generation operation mode, the valve configuration and fluid flow of the system are precisely controlled to optimize the output of heat and electricity. The first valve 231, the second valve 232, the eighth valve 238 and the ninth valve 239 on the first heat exchange pipeline 280 are in an open state, ensuring that the first circulating water can circulate to realize the heat exchange function between the geothermal direct supply heat exchanger 120, the condenser 240 and the heat release heat exchanger 190, and the heat is released to the heating user 210 through the heat release heat exchanger 190, thereby completing the transfer of heat energy. At the same time, the fifth valve 235 and the seventh valve 237 on the geothermal water pipeline 270 are also kept open, so that the geothermal water is extracted from the production well 250 and returned to the ground through the recharge well 260 after a series of heat exchange processes. In addition, the second water supply valve 421 configured on the second water supply pipeline 420 is kept open so that a part of the geothermal tail water can be stored in the water storage tank 400. This process not only ensures the sustainable use of geothermal water resources, but also realizes the power generation of the residual pressure and potential energy of geothermal tail water through the dual-purpose water turbine for pumping power generation. Since the main goal of the system in this working mode is to meet the heating demand and generate electricity using the residual pressure of geothermal tail water, the third valve 233, the fourth valve 234 and the sixth valve 236 on the water circulation pipeline 310 are closed. Such a configuration avoids unnecessary fluid flow and energy loss, and ensures that the energy output of the system matches the requirements of the current working mode.

[0058] 2. Heating, heat storage and power generation operation mode:

[0059] Preferably, if Figure 3 As shown, when the heating load in the heat-electric linkage optimization stage is relatively small and the electricity price is low, the geothermal system operates at full load, and part of the heat that exceeds the user's heating load demand is stored in the heat storage and electricity storage dual-purpose water tank 160. While providing heat, the second turbine 220 in the geothermal recharge well 260 is used to recover the residual pressure and tail water potential energy of the geothermal tail water for power generation. While providing heat, the geothermal system uses its own resources to generate electricity, thereby reducing the electricity consumption of the geothermal system and improving geothermal efficiency.

[0060] Specifically, geothermal water is extracted from the production well 250 and first enters the geothermal direct supply heat exchanger 120, where it releases heat to the heating system, and at the same time the water temperature drops to form primary cooling water. In this process, the thermal energy of the geothermal water is used to meet the heating needs of users. Next, the primary cooling water flows into the geothermal tail water heat exchanger 130, which is connected to the evaporator 110 of the water source heat pump 150, further releasing heat to provide a low-temperature heat source for the water source heat pump 150. The condenser 240 of the water source heat pump 150 transfers the absorbed heat to the dual-purpose water tank 160 for heat storage and electricity storage, increases the water temperature in the water tank, and realizes heat storage. At the same time, after the geothermal water flows through the geothermal tail water heat exchanger 130, its high potential energy is used to drive the dual-purpose water turbine for pumping and power generation to generate electricity, realizing the recovery of the residual pressure and potential energy of the geothermal tail water. This power generation process not only improves the efficiency of energy utilization, but also creates additional power output for the system. The heat stored in the dual-purpose heat storage and electricity storage water tank 160 can be stored during periods of low heating demand, thereby optimizing the economy of the system. In addition, the system also effectively transfers the heat stored in the dual-purpose heat storage and electricity storage water tank 160 to the heating user 210 during periods of high heating demand through the heat release water pump 180 and the heat release heat exchanger 190, ensuring that the user's heating needs are met. The hot water pump 200 is responsible for delivering the hot water in the heat release heat exchanger 190 to the user, completing the entire heating process. The opening and closing states of each valve in the heating storage and power generation operation mode are consistent with those in the heating power generation operation mode, and will not be repeated here.

[0061] 3. Heat release and heating operation mode:

[0062] Preferably, if Figure 4 As shown, during the peak electricity price or peak electricity price period in the heat-electricity linkage optimization stage, the operation of the geothermal heat-electricity dual storage and supply system is switched to the heat release and heating operation mode. At this time, the system mainly uses the heat stored in the heat storage and electricity storage dual water tank 160 to meet the user's heating needs, without relying on the main heat source equipment of the geothermal system. In this operation mode, the main heat source equipment such as the geothermal direct supply heat exchanger 120 and the geothermal tail water heat exchanger 130 are suspended to reduce power consumption during periods with higher electricity prices.

[0063] Specifically, the heat storage and electricity storage dual-purpose water tank 160 is connected to the heat release heat exchanger 190 through the heat release water pump 180, and the hot water stored in the water tank is pumped to the heat release heat exchanger 190 to exchange heat with the second circulating water of the heating user 210. The heat release heat exchanger 190 releases heat to heat the user's second circulating cold water, and then the second circulating warm water carrying heat is transported to the heating user 210 to provide the required heat. At the same time, the water after heat release in the heat release heat exchanger 190, that is, the first circulating warm water after the temperature drops, returns to the heat storage and electricity storage dual-purpose water tank 160 through the return water pipe, that is, the first heat exchange pipeline 280, forming a closed-loop heating system. The hot water pump 200 plays a key role in this process. It ensures that the circulating water of the heating user 210 can flow effectively and transfers the heat in the heat release heat exchanger 190 to the user in time. The outlet of the heat release heat exchanger 190 is directly connected to the heating user 210 to ensure the direct supply of heat.

[0064] Since this operation mode focuses on heat supply rather than power generation, power generation related equipment, such as the first turbine 100 and the second turbine 220, will not operate. The eighth valve 238 and the ninth valve 239 are in an open state to allow hot water to flow to the heating user 210; the remaining valves are closed to prevent system resources from being used for power generation during the period when power generation is not required.

[0065] 2. Energy storage and release optimization stage

[0066] 1. Energy storage operation mode in the energy storage and release optimization stage:

[0067] Preferably, if Figure 5 As shown, in the energy storage and release optimization stage and the electricity storage operation mode, the geothermal thermal power dual storage and supply system mainly uses electricity during the off-peak electricity price period to store energy. At this time, the system converts electrical energy into high-potential energy and stores it in the thermal and electricity storage dual-use water tank 160. In this operation mode, the first turbine 100 and the second turbine 220 play a key role. They operate during periods of low electricity demand and cost, extracting groundwater and transporting it to the thermal and electricity storage dual-use water tank 160 and the water storage tank 400.

[0068] Since the goal of this operation mode is energy storage rather than heating or power generation, the equipment related to heating, such as the heat dissipation pump 180, the heat dissipation heat exchanger 190, and the equipment related to power generation, such as the water source heat pump 150, are all in a non-operating state. Specifically, in this operation mode, the valves connected to the water storage tank 400 and the heat storage and electricity storage dual-use water tank 160 need to be properly configured to allow the storage of high potential water. This includes ensuring that the valves on the water circulation pipeline 310 and the first water replenishment pipeline 410, such as the third valve 233 and the first water replenishment valve 411, are in an open state so that the geothermal water can flow into the heat storage and electricity storage dual-use water tank 160 or out of the water storage tank 400. In addition, the fourth valve 234 and the sixth valve 236, located near the two wells, will also remain in an open state to facilitate the pumping operation of the turbine. Accordingly, the valves associated with the non-operating equipment will be closed to prevent fluid flow and reduce energy loss.

[0069] In general, in the energy storage operation mode during the energy storage and release optimization stage, the system optimizes the utilization of electric energy by intelligently controlling the opening and closing of valves, converting electric energy during off-peak electricity price periods into high-level potential energy and storing it, preparing for energy demand during peak electricity price periods, while also providing guarantees for the economic operation of the coupled solar energy system.

[0070] 2. Power generation operation mode in the energy storage and energy release optimization stage:

[0071] Preferably, if Figure 6 As shown, in the power generation operation mode of the energy storage and release optimization stage, the geothermal thermal power dual storage and supply system mainly drives the power generation process by releasing the high potential water stored in the thermal and power storage dual water tank 160 and the water storage tank 400 during the peak electricity price period. At this time, the system's goal is to generate electricity when the electricity price is high to maximize economic benefits.

[0072] Specifically, the high potential water stored in the heat and electricity storage dual-use water tank 160 and the water storage tank 400 is released by opening the control valve and discharged into the well through the water circulation pipeline 310 and the water discharge pipeline 430. In this process, the first turbine 100 and the second turbine 220 are transformed into generators, which use the potential energy of the water flow to rotate in the opposite direction, convert mechanical energy into electrical energy, and supply it to the power grid.

[0073] In order to ensure the smooth progress of the power generation process, the valves of the equipment not related to power generation, such as the heating system, will remain closed to avoid unnecessary loss of energy. At the same time, the valves on the water circulation pipeline 310, such as the fourth valve 234 and the sixth valve 236 near the water well, need to be opened to allow the water to flow smoothly into the well and drive the turbine to generate electricity. In addition, the valves connected to the heat and electricity storage dual-purpose water tank 160, such as the third valve 233, can be adjusted according to the water level and power generation demand to control the release rate of the water flow.

[0074] In the power generation operation mode of the energy storage and release optimization stage, the system can monitor the power grid price and energy storage status in real time by equipping intelligent control equipment, and optimize power generation efficiency and cost-effectiveness by accurately controlling the opening and closing of valves and the operation of turbines. This operation mode enables the geothermal heat and power dual storage energy supply system to not only provide efficient cogeneration in the heat and power linkage optimization stage, but also flexibly convert to power generation operation mode in the energy storage and release optimization stage, achieving efficient energy utilization and improved economic benefits throughout the year.

[0075] Example 2

[0076] This embodiment is a further improvement on the above-mentioned embodiment, and the repeated contents will not be repeated here.

[0077] The thermal power dual storage energy supply system involved in this embodiment uses the turbines in the production well 250 and the reinjection well 260, and dynamically adjusts the operation mode according to the fluctuation of power grid electricity prices, heating demand and the demand for the consumption of new energy power generation. The system mainly involves the following energy conversion modes:

[0078] 1. Operation mode of heat and power linkage optimization stage

[0079] In the heat-electricity linkage optimization stage, the first turbine 100 runs forward to extract geothermal water in the production well for heat energy conversion. At the same time, the second turbine 220 generates electricity in the reverse direction using the potential energy of the geothermal tail water. The power generation of the second turbine 220 can be calculated as follows:

[0080] P2=η t2 ρgh2Q2

[0081] in:

[0082] η t2 is the efficiency of the second turbine 220,

[0083] ρ is the density of geothermal tail water,

[0084] g is the acceleration due to gravity,

[0085] h2 is the water head height of the second turbine 220,

[0086] Q2 is the water flow rate flowing through the second water turbine 220 .

[0087] 2. Operation mode of energy storage and energy release optimization stage

[0088] In the energy storage and release optimization stage, the first turbine 100 and the second turbine 220 operate synchronously, and the electrical energy is converted into potential energy and stored in the heat and electricity storage dual-purpose water tank 160. The power conversion formula is:

[0089] E in =P elt

[0090] in:

[0091] E in is the input electrical energy,

[0092] P el is the power provided by the grid,

[0093] t is the time.

[0094] Therefore, the design of the system in this embodiment can balance the conversion requirements between geothermal energy and solar energy, maximize power generation and energy supply efficiency, and adapt to grid fluctuations and energy demands in different seasons.

[0095] Figure 7 and Figure 8 The schematic diagrams of solar radiation illumination and solar power generation are shown respectively. According to the performance of solar photovoltaic panels, the power generation is affected by the ambient temperature θ amb (t) and solar irradiance G(t), the photovoltaic panel temperature θ pv The calculation formula of (t) is:

[0096] θ pv (t) = θ amb (t)+((θ noct -θ ref )G(t)) / G ref

[0097] in:

[0098] θ noct is the photovoltaic panel temperature under standard conditions,

[0099] θ ref is the reference temperature,

[0100] G ref is the reference solar irradiance.

[0101] The power generation efficiency formula of photovoltaic panels is:

[0102] η pv (t) = η pv，n [1-β pv (θ pv (t)-θ ref )]

[0103] in:

[0104] η pv，n is the photovoltaic panel power generation efficiency under standard conditions,

[0105] β pv is the temperature coefficient.

[0106] The power generated by the photovoltaic panel is:

[0107] P pv (t) = A pv η pv (t)G(t)

[0108] in:

[0109] A pv is the area of ​​a single photovoltaic panel,

[0110] P pv is the power generated by the photovoltaic panel.

[0111] The formula for the grid-connected power generation of photovoltaic panels is:

[0112] E=(KH A P AZ ) / Es

[0113] in:

[0114] E p is the amount of electricity generated on the grid, in kWh,

[0115] K is the comprehensive efficiency coefficient,

[0116] H A is the total solar radiation on the horizontal surface, in kWh / m 2 ,

[0117] E s is the radiation under standard conditions, with a value of 1kW / m 2 ,

[0118] P AZ is the installed capacity of PV panels, in kW.

[0119] After simulation calculations, when distributed photovoltaic power generation is not allowed to be connected to the grid, power dispatch is uneven, and the cost of battery energy storage is too high, the use of deep geothermal heating energy storage systems in buildings can help improve the efficiency of photovoltaic system power generation and increase the economic value of photovoltaic systems.

[0120] The analysis is conducted from the perspectives of power saving ratio, power generation income, power storage income under peak and valley electricity prices, and the corresponding economic calculation formula is introduced. The following is an economic evaluation of a system with a heating area of ​​100,000 square meters:

[0121] 1. Calculation of power saving ratio in the heat and power linkage optimization stage

[0122] After the system of the present invention is adopted, the annual power saving ratio on the well pump side in the heat-electricity linkage optimization stage is about 40% compared with the original system, and the annual power saving ratio on the well pump side of the original system is:

[0123] ΔEpump =E pump，original ×40%

[0124] in:

[0125] Δ Epump It is the power saving in the optimization stage of thermal power linkage.

[0126] E pump，original is the annual power consumption of the original system.

[0127] Compared with the overall geothermal heating system, the annual electricity saving ratio is about 16%, namely:

[0128] ΔE total =E total，original ×16%

[0129] in:

[0130] ΔE total is the total annual power saving of the system,

[0131] E total，original It is the annual power consumption of the original geothermal heating system.

[0132] 2. Power generation and benefits of recovering geothermal tailwater residual pressure potential energy

[0133] In the heating season, by recovering the residual pressure potential energy of geothermal tail water, the annual power generation is 180,000 kWh, and the corresponding power generation income is 150,000 yuan. The calculation formula of power generation and income is as follows:

[0134] E( gen，heat )=180,000kWh

[0135] R( gen，heat )=E( gen，heat )×p elec

[0136] in:

[0137] E( gen，heat ) is the power generation in the heating season,

[0138] R( gen，heat ) is the power generation income in the heating season,

[0139] p elec is the electricity price (unit: yuan / kWh).

[0140] The revenue from power generation is:

[0141] R( gen，heat ) = 180,000 kWh × 0.83 yuan / kWh = 150,000 yuan

[0142] 3. Energy storage and energy release optimization stage Peak and valley electricity price storage and power generation function benefits

[0143] In the energy storage and energy release optimization stage, the system uses the peak and valley electricity price periods to store and generate electricity, achieving an annual storage of 250,000 kWh and a power generation income of more than 210,000 yuan. The formula for storage and power generation income is as follows:

[0144] E( gen，nonheat )=250,000kWh

[0145] R( gen，nonheat )=E( gen，nonheat )×p( elec，nonheat )

[0146] in:

[0147] E( gen，nonheat ) is the power generation in the energy storage and energy release optimization stage,

[0148] R( gen，nonheat ) is the power generation income in the energy storage and energy release optimization stage,

[0149] p( elec，nonheat ) is the electricity price in the energy storage and energy release optimization stage (yuan / kWh).

[0150] According to the given data, the power generation income is:

[0151] R( gen，nonheat ) = 250,000 kWh × 0.84 yuan / kWh = 210,000 yuan

[0152] 4. Total power saving and economic benefits

[0153] The overall annual power saving of the system can be calculated by the sum of the power generation in the heat and power optimization stage and the energy storage and release optimization stage:

[0154] E( total，gen )=E( gen，heat )+E( gen，nonheat )=180,000kWh+250,000kWh=430,

[0155] 000kWh

[0156] The corresponding total revenue is:

[0157] R( total，gen )=R( gen，heat )+R( gen，nonheat ) = 150,000 yuan + 210,000 yuan = 360,000 yuan

[0158] Yuan

[0159] 5. Comprehensive power saving rate

[0160] Compared with the original geothermal heating system, the comprehensive power saving rate can be calculated by the annual power saving of the system to the total power consumption of the original system:

[0161] η save =(ΔE total ) / E( total，original )=16%

[0162] In summary, in terms of economy, for a system with a heating area of ​​100,000 square meters, after adopting the present invention, the annual electricity saving ratio on the well pump side in the heat-electricity linkage optimization stage is about 40% compared with the original system, and the annual electricity saving ratio is about 16% compared with the overall geothermal heating system. In the heating season, the residual pressure potential energy of geothermal tail water is recovered to generate 180,000 kw·h of electricity, and the power generation income is 150,000 yuan. In the energy storage and release optimization stage, the system adopts the storage and power generation function during the peak and valley electricity price period. The energy storage and release optimization stage can achieve an annual power storage of 250,000 kw·h and a power generation income of more than 210,000 yuan.

[0163] Example 3

[0164] This embodiment is a further improvement on the above-mentioned embodiment, and the repeated contents will not be repeated here.

[0165] In this embodiment, the thermal power dual storage energy supply system also introduces the concept of a mixed operating stage, which is used to cope with fluctuations in heating demand, changes in grid electricity prices, drops in geothermal water temperature, and the balance between heat and electricity. Among them, changes in heating demand will affect the use of geothermal water; grid electricity prices in different time periods will affect power generation strategies; geothermal water temperature will drop after multiple cycles, affecting its heat recovery value; and the balance point between heating revenue and power generation revenue will affect the balance between heat and electricity.

[0166] Specifically, the heating revenue R h The calculation formula is:

[0167] R h =P h ×C h

[0168] In the formula,

[0169] P h :Heating demand (unit: KW)

[0170] C h :Heating charge per item (unit: yuan / KW·h)

[0171] Power generation income R e The calculation formula is:

[0172] R e =P e ×C e

[0173] In the formula,

[0174] P e :Power generation demand (unit: KW)

[0175] C e : On-grid electricity price (unit: yuan / KW·h)

[0176] Assuming the specific heat capacity of geothermal water is C, the thermal energy per unit mass of geothermal water is E w for:

[0177] E w =c×(T w -T out )

[0178] In the formula,

[0179] T w :The initial temperature of geothermal water (unit: °C)

[0180] T out :The temperature of geothermal water after multiple cycles (unit: ℃)

[0181] Total thermal energy E of geothermal water total for:

[0182] E total =E w ×Q1×t

[0183] In the formula,

[0184] Q1: Water flow rate flowing through the first turbine 100 (unit: m 3 / s)

[0185] The pumping power P1 of the first turbine 100 is:

[0186] P1=η t 1×ρ×g×h1×Q1

[0187] In the formula,

[0188] η t 1: Efficiency of the first turbine 100

[0189] ρ: Density of geothermal tail water (unit: kg / m 3 )

[0190] g: gravitational acceleration (unit: m / s 2 )

[0191] h1: water head height of the first turbine 100 (unit: m)

[0192] The pumping power P2 of the second turbine 220 is:

[0193] P2=η t 2×ρ×g×h2×Q2

[0194] In the formula,

[0195] η t 2: Efficiency of the second turbine 220

[0196] Thus, the total revenue R of the thermal power dual storage energy supply system of the present invention can be calculated. total :

[0197] R total =R h +R e

[0198] In order to find the best balance between thermal energy and electrical energy, the total revenue R total Assuming that at a certain time point t, the system of the present invention can decide whether to use geothermal water for heating or power generation, the decision can be made through the following steps:

[0199] Calculate the heating revenue R at the current moment h (t) and power generation revenue R e (t). Compare R h (t) and R e (t), choose the option with higher return, if R h (t)>R e (t), geothermal water is preferred for heating if R e (t)>R h (t), geothermal water is used for power generation first. The above decision can be expressed by the following decision formula:

[0200] If R h (t)>R e (t), mP1=η t 1×ρ×g×h1×Q1 and P2=0I

[0201] If R e (t)>R h (t), then P1 = 0 and P2 = η t 2×ρ×g×h2×Q2.

[0202] Wherein, P1=0 means that the first water turbine 100 is suspended, and the geothermal water will be completely used in the power generation operation of the second water turbine 220. And P2=0 means that the second water turbine 220 is suspended, and the geothermal water will be completely used in the heating operation of the first water turbine 100.

[0203] In the mixed working stage, the system of the present invention can introduce a dynamic adjustment factor α to represent the weight ratio of the thermal energy recovery value of geothermal water to the power generation income. When α is larger, the system is more inclined to utilize the thermal energy of geothermal water. When α is smaller, the system is more inclined to generate electricity.

[0204]

[0205] Based on this, the decision formula can be finally adjusted to:

[0206] If α×R h (t)>R e (t), then P1=η t 1×ρ×g×h1×Q1 and P2=0

[0207] If α×R h (t)<R e (t), then P1 = 0 and P2 = η t 2×ρ×g×h2×Q2

[0208] Therefore, the system of the present invention can dynamically adjust the value of α by real-time monitoring of the temperature of geothermal water, heating demand and grid electricity price to achieve the optimal thermal and electrical energy utilization strategy. This will ensure that the system maximizes economic benefits while meeting heating demand.

[0209] Preferably, according to the present invention, the α value can be dynamically adjusted according to the monitored geothermal water temperature, heating demand and grid electricity price, wherein the temperature of geothermal water directly affects its heat recovery value, the change of heating demand determines whether the system needs to give priority to heating or power generation, and the grid electricity price in different time periods affects the economic benefits of power generation. Considering the influence of geothermal water temperature, the higher the geothermal water temperature, the greater the heat recovery value, and the α value should be increased. Considering the influence of heating demand, the greater the heating demand, the α value should be increased. Considering the influence of grid electricity price, the higher the grid electricity price, the greater the power generation income, and the α value should be reduced.

[0210] According to the temperature change and flow rate of geothermal water, the heat energy recovery value of geothermal water can be calculated:

[0211] E w =c×(T w -T out )

[0212] E total =E w ×Q1×t

[0213] Calculate heating revenue based on heating demand and heating charge unit price:

[0214] R h =P h ×C h

[0215] The power generation income is calculated based on the power generation of the second turbine 220 and the on-grid electricity price:

[0216] P1=η t 1×ρ×g×h1×Q1

[0217] P2=η t 2×ρ×g×h2×Q2

[0218] R e =P2×C e

[0219] The initial weight ratio α0 is calculated by using the ratio of the heat recovery value of geothermal water to the power generation income:

[0220]

[0221] The dynamic adjustment of α should take into account the influence of geothermal water temperature. The higher the geothermal water temperature, the greater the heat recovery value, and the α value should be increased. The influence of heating demand should also be considered. The greater the heating demand, the greater the α value should be. The influence of grid electricity price should also be considered. The higher the grid electricity price, the greater the power generation income, and the α value should be reduced. The dynamic adjustment formula is:

[0222]

[0223] in:

[0224] k T : The influence coefficient of geothermal water temperature (e.g., value range: 0.1 to 0.5);

[0225] k P :The influence coefficient of heating demand (e.g. value range: 0.1~0.5)I

[0226] k C : The impact coefficient of the on-grid electricity price (e.g., value range: 0.1 to 0.5);

[0227] T max and T min : Maximum and minimum values ​​of geothermal water temperature;

[0228] P max : Maximum value of heating demand;

[0229] C max : The maximum value of the on-grid electricity price.

[0230] In summary, in the system and method of the present invention, the α value is dynamically adjusted according to the actual monitored data, so as to maximize the economic benefits of the system while meeting the heating demand.

[0231] Example 4

[0232] This embodiment is a further improvement on the above-mentioned embodiment, and the repeated contents will not be repeated here.

[0233] According to this embodiment, the thermal power dual storage and energy supply system of the present invention can consider the rotation of pumping water and returning water from two or more wells to maximize power generation and geothermal utilization, wherein the comprehensive considerations when determining the active wells for pumping water and the return wells for recycling can include the following categories:

[0234] Geothermal water temperature: The temperature of geothermal water directly affects its heat recovery value.

[0235] Groundwater level: The drop in groundwater level will affect the subsequent pumping effect.

[0236] Heating demand: Changes in heating demand determine whether the system needs to prioritize heating or power generation.

[0237] Grid electricity price: The grid electricity price in different time periods affects the economic benefits of power generation.

[0238] Well water temperature: Returning cold water will cause the well water temperature to drop, affecting subsequent heat energy extraction.

[0239] Specifically, the active well and the return well can be determined according to the following steps:

[0240] 1. Initialization:

[0241] Set the initial active well i active and initial return water well i recharge .

[0242] Initialize the groundwater level Li and water temperature T(w,i) of each well.

[0243] 2. Calculate the heat recovery value of geothermal water:

[0244] E w，i =c×(T w，i -T out，i )

[0245] E total，i =E w，i ×Q1×t

[0246] Where, T(w,i): initial temperature of geothermal water in the i-th well (unit: °C)

[0247] T(out,i): The temperature of the geothermal water in the i-th well after multiple cycles (unit: °C)

[0248] 3. Calculate heating benefits:

[0249] R h =Ph ×C h

[0250] 4. Calculate power generation income:

[0251] P1=η t 1×ρ×g×h1×Q1

[0252] P2=η t 2×ρ×g×h2×Q2

[0253] R e =P2×C e

[0254] 5. Calculate the initial weight ratio α0:

[0255]

[0256] 6. Dynamically adjust alpha value:

[0257]

[0258] 7. Select active wells and return water wells:

[0259] Select active well: Select the well with the highest groundwater level and the highest water temperature as the active well. active .

[0260] Select the return water well: Select the well with the lowest groundwater level and the lowest water temperature as the return water well. recharge .

[0261] 8. Update groundwater level and water temperature:

[0262] Groundwater level: Update the groundwater level of each well based on the flow rate of pumped and returned water.

[0263] Water temperature: Update the water temperature of each well based on the flow rate of pumped and returned water.

[0264] 9. Determine whether to switch wells:

[0265] If the groundwater level in the active well is below L min Or the water temperature is lower than T min , switch to the next well that meets the conditions.

[0266] If the groundwater level in the return well is higher than that in other wells or the water temperature is higher than T min , switch to the next well that meets the conditions.

[0267] The above algorithm can dynamically adjust the active wells and return water wells according to the actual monitoring data to maximize the effect of power generation and geothermal utilization. When designing the algorithm of "judging whether to switch wells", the water temperature change rate and the groundwater level change rate are two important parameters, which are used to predict the future state of the wells, so as to make more reasonable decisions. The present invention discloses a method for analyzing these two parameters as follows.

[0268] Preferably, when calculating the rate of change of the groundwater level, the groundwater level can be measured regularly (for example, every hour) by a water level sensor installed in the well, and the data of each measurement is recorded to form time series data.

[0269] The rate of change of groundwater level can be estimated using the difference between two consecutive measurements, namely:

[0270]

[0271] Wherein, L(t) is the groundwater level at the current time, L(t-1) is the groundwater level at the previous time point, and Δt is the time interval (e.g., 1 hour).

[0272] The groundwater level change rate can also be calculated using the sliding average method to reduce noise, that is:

[0273]

[0274] Here, n is the size of the sliding window.

[0275] A linear regression model is used to predict the trend of groundwater level, namely:

[0276] L(t)=β0+β + t+∈

[0277] Among them, β1 is the rate of change of groundwater level, which can be solved by the least squares method.

[0278] Preferably, when calculating the rate of change of groundwater temperature, the water temperature can be measured regularly (for example, every hour) by a temperature sensor installed in the well, and the data of each measurement can be recorded to form time series data.

[0279] The rate of change of groundwater temperature can be estimated using the difference between two adjacent measurements, namely:

[0280]

[0281] Wherein, T(t) is the water temperature at the current time, T(t-1) is the water temperature at the previous time point, and Δt is the time interval (e.g., 1 hour).

[0282] The groundwater temperature change rate can also be calculated using the sliding average method to reduce noise, that is:

[0283]

[0284] Here, n is the size of the sliding window.

[0285] Use a linear regression model to predict the changing trend of water temperature, namely:

[0286] T(t)=β0+β1t+E

[0287] Among them, β1 is the rate of change of water temperature, which can be solved by the least squares method.

[0288] Preferably, the obtained groundwater level change rate and / or the obtained groundwater temperature change rate are used to predict the groundwater level and / or groundwater temperature at a certain time point in the future, that is:

[0289] L(t+Δt)=L(t)+groundwater level change rate×Δt

[0290] T(t+Δt)=T(t)+water temperature change rate×Δt

[0291] If the predicted groundwater level is lower than the minimum allowable value L min , then it is necessary to switch well I if the predicted water temperature is lower than the minimum allowable value T min , you need to switch wells.

[0292] Therefore, in the method and system of the present invention, the groundwater level change rate and the water temperature change rate can be combined to comprehensively judge whether it is necessary to switch wells. For example:

[0293] If the groundwater level change rate indicates that the groundwater level will soon be lower than the minimum allowable value, switch well I first; if the groundwater level change rate is within the safe range, but the water temperature change rate indicates that the water temperature will soon be lower than the minimum allowable value, switch wells; if both the groundwater level and the water temperature are close to the critical value, the predicted values ​​of the two can be comprehensively considered to select the most appropriate well for switching.

[0294] Through these methods, the status of the well can be predicted more accurately, so that more reasonable decisions can be made to ensure the efficient operation of the system and the rational use of resources.

[0295] It should be noted that the above-mentioned specific embodiments are exemplary, and those skilled in the art can come up with various solutions inspired by the disclosure of the present invention, and these solutions also belong to the disclosure scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the present invention specification and its drawings are illustrative and do not constitute a limitation of the claims. The scope of protection of the present invention is defined by the claims and their equivalents. The present invention specification contains multiple inventive concepts, such as "preferably" or "according to a preferred embodiment", which means that the corresponding paragraph discloses an independent concept, and the applicant reserves the right to file a divisional application based on each inventive concept. Throughout the text, the features guided by "preferably" are only an optional method and should not be understood as a must-have setting. Therefore, the applicant reserves the right to abandon or delete the relevant preferred features at any time.

Claims

1. A thermal and electric dual storage and energy supply system, characterized in that: The system comprises a first water turbine (100) arranged in a production well (250) and a second water turbine (220) arranged in a recharging well (260). The system can adjust the operation modes of the first water turbine (100) and the second water turbine (220) according to fluctuations in power grid electricity prices, heating demand, and new energy power generation and consumption demand, so as to switch the pumping function and power generation function of the two water turbines, wherein: In the heat-electricity linkage optimization stage, the first water turbine (100) operates in a forward direction to extract geothermal water in the production well (250), and the heat in the geothermal water can be stored in a heat-electricity storage dual-purpose water tank (160) and a water storage tank (400), and the second water turbine (220) operates in a reverse direction using the potential energy of geothermal tail water converted from geothermal water that has completed heat exchange to generate electricity for a power grid; In the energy storage and release optimization stage, the first water turbine (100) and the second water turbine (220) operate synchronously to convert electrical energy into potential energy and store it in the dual-purpose heat and electricity storage water tank (160) and the water storage tank (400), or use the high potential energy water stored in the dual-purpose heat and electricity storage water tank (160) and the water storage tank (400) to reversely generate electricity to supply the power grid.

2. The system according to claim 1, characterized in that It comprises a geothermal direct supply heat exchanger (120) and a geothermal tail water heat exchanger (130), which are connected in series with the first water turbine (100) and the second water turbine (220) via a geothermal water pipeline (270). The first water turbine (100) is connected to the input end of the geothermal direct supply heat exchanger (120) through the geothermal water pipeline (270). After the geothermal direct supply heat exchanger (120) performs heat exchange, the cooled geothermal water is then sent to the geothermal tail water heat exchanger (130) through the geothermal water pipeline (270). After the geothermal tail water heat exchanger (130) further recovers heat, the geothermal tail water uses high potential energy to drive the second water turbine (220) to rotate, thereby generating electricity and being incorporated into the power grid.

3. The system according to claim 1 or 2, characterized in that: The dual-purpose water tank (160) for storing heat and electricity and the geothermal direct heat exchanger (120) are connected to each other via a first heat exchange pipeline (280). A hot water storage pump (170) is installed on the first heat exchange pipeline (280). The inlet of the pump is directly connected to the outlet of the dual-purpose water tank (160) for storing heat and electricity, and the outlet of the pump is connected to the inlet of the geothermal direct heat exchanger (120). The geothermal water enters the geothermal direct supply heat exchanger (120) through the geothermal water pipeline (270), where it exchanges heat with the first circulating warm water to form primary cooling water. The first circulating warm water in the first heat exchange pipeline (280) absorbs heat and is converted into first circulating hot water. The hot water storage pump (170) drives the first circulating hot water to circulate along the first heat exchange pipeline (280) and transports the heat to the dual-purpose heat and electricity storage water tank (160) for storage.

4. The system according to any one of claims 1 to 3, characterized in that: The geothermal tail water heat exchanger (130) is connected to the water source heat pump (150) via an internal heat exchange pipeline (290). The water source heat pump (150) comprises an evaporator (110) and a condenser (240) which are interconnected through a heat exchange process, wherein the evaporator (110) is connected to a geothermal tail water heat exchanger (130) through an internal heat exchange pipeline (290), and the condenser (240) is connected to the heat storage and electricity storage dual-purpose water tank (160) through the first heat exchange pipeline (280). The internal heat exchange pipeline (290) is provided with an intermediate water pump (140) for providing driving force for the flow of internal circulating water. The internal circulating cold water starts from the outlet of the evaporator (110), passes through the internal heat exchange pipeline (290) and enters the inlet of the geothermal tail water heat exchanger (130). Primary cooling water is introduced into the other inlet of the geothermal tail water heat exchanger (130). The primary cooling water releases heat in the geothermal tail water heat exchanger (130) to be converted into geothermal tail water, and the internal circulation cold water absorbs heat to be converted into internal circulation warm water.

5. The system according to any one of claims 1 to 4, characterized in that: The first heat exchange pipeline (280) is designed as a double-branch structure, one end of which is connected to the outlet of the hot water storage pump (170), and the other end of which is respectively connected to the condenser (240) and the geothermal direct heat exchanger (120). The first circulating warm water circulating in the first heat exchange pipeline (280) flows out from the dual-purpose water tank (160) for heat storage and electricity storage, enters the condenser (240) to perform heat exchange with the internal circulating warm water to increase the temperature to become the first circulating hot water, and the first circulating hot water after heat exchange returns to the dual-purpose water tank (160) for storage through one branch of the first heat exchange pipeline (280), and the other branch is used to directly send the first circulating hot water to the geothermal direct supply heat exchanger (120) to perform heat exchange with the geothermal water.

6. The system according to any one of claims 1 to 5, characterized in that: The system is provided with a heat-releasing heat exchanger (190) connected to the heat-storage and electricity-storage dual-purpose water tank (160) via the first heat exchange pipeline (280). The first heat exchange pipeline (280) is provided with a heat release water pump (180) for driving the circulating water in the heat exchange pipeline to flow, so as to ensure that the first circulating water exchanges heat in the heat release heat exchanger (190). The heat release heat exchanger (190) is connected to the heat supply user (210) via a second heat exchange pipeline (300). A hot water pump (200) is arranged on the second heat exchange pipeline (300) to drive the flow of the second circulating water in the pipeline.

7. The system according to any one of claims 1 to 6, characterized in that: The dual-purpose water tank (160) for heat storage and electricity storage is connected to the production well (250) and the reinjection well (260) via a water circulation pipeline (310); the water storage tank (400) is connected to the production well (250) and the reinjection well (260) via a first water replenishment pipeline (410) and a second water replenishment pipeline (420) connected to the geothermal water pipeline (270); the well turbine can extract geothermal water from the production well (250) and / or the reinjection well (260), and transport it to the dual-purpose water tank (160) for storage via the water circulation pipeline (310), and / or transport it to the water storage tank (400) for storage via the first water replenishment pipeline (410) and the second water replenishment pipeline (420), thereby converting electrical energy into high potential energy of water. The dual-purpose heat and electricity storage water tank (160) and / or the water storage tank (400) can release the stored geothermal water back to the production well (250) and / or the reinjection well (260) according to system requirements, so as to convert the high potential energy back into electrical energy by driving the two turbines to rotate in opposite directions.

8. The system according to any one of claims 1 to 7, characterized in that: The system is equipped with several valves to control the flow of fluid. The first valve (231) and the eighth valve (238) are located on the first heat exchange pipeline (280) on one side of the heat storage and electricity storage dual-purpose water tank (160), and the second valve (232) and the ninth valve (239) are located on the first heat exchange pipeline (280) on the other side of the heat storage and electricity storage dual-purpose water tank (160). The geothermal water pipeline (270) is respectively provided with a fifth valve (235) and a seventh valve (237) at positions close to the production well (250) and the reinjection well (260) to control the well water reinjection process. On the water circulation pipeline (310), the third valve (233) is arranged near the heat and electricity storage dual-purpose water tank (160), and the fourth valve (234) and the sixth valve (236) are arranged near the two water wells. The first water supply pipeline (410) is provided with a first water supply valve (411) for controlling the on-off of geothermal water extracted from the production well (250) by the first water turbine (100); The second water replenishment pipeline (420) is provided with a second water replenishment valve (421) for controlling the on-off of geothermal tail water obtained by heat exchange from the geothermal tail water heat exchanger (130) or for controlling the on-off of geothermal water extracted from the recharging well (260) by the second water turbine (220); The water discharge pipe (430) is provided with a water discharge valve (431) for controlling the flow of high potential energy water in the water storage tank (400) to the geothermal water pipeline (270).

9. The system according to any one of claims 1 to 8, characterized in that: In the heat-power linkage optimization stage, the system can switch between three operating modes: heating power generation, heating storage power generation, and heat release heating, according to the heating demand and electricity price period. During periods when the demand for heat is high and the electricity price is high, the system switches to a heat supply and power generation operation mode to give priority to meeting the heat demand, and generates electricity through the second turbine (220) to achieve cogeneration of heat and power; During a period when the demand for heat is small and the electricity price is low, while meeting the demand for heat, the system switches to a heat supply and heat storage power generation operation mode to store excess heat in the heat storage and power storage dual-purpose water tank (160), and uses the second water turbine (220) to generate electricity; During the peak electricity price period, the system switches to the heat release and heating operation mode to utilize the heat stored in the heat storage and electricity storage dual-purpose water tank (160) for heating, thereby reducing the operating cost.

10. The system according to any one of claims 1 to 9, characterized in that: In the energy storage and release optimization stage, the system switches between the energy storage operation mode and the power generation operation mode according to the peak and valley periods of electricity prices, wherein: The system utilizes the off-peak electricity price period to pump groundwater into the heat and electricity storage dual-purpose water tank (160) and / or the water storage tank (400) through the first water turbine (100) and / or the second water turbine (220) to store high potential energy, thereby realizing an electricity storage operation mode; The system utilizes the peak electricity price period to release water with high potential energy into the production well (250) and / or the reinjection well (260), and generates reverse power through the first turbine (100) and / or the second turbine (220), thereby realizing a power generation operation mode.

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