Energy storage and heat storage system and energy storage and heat storage method

Abstract

The invention relates to the field of energy storage, and provides an energy storage and heat storage system and an energy storage and heat storage method. The energy storage and heat storage system comprises an air compressor; the heat storage heat exchanger is in fluid communication with the air compressor; the regenerative heat exchanger is connected to the heat storage heat exchanger in parallel through a first loop; a photo-thermal heat collector; the photo-thermal heater is in fluid communication with the photo-thermal collector, and the photo-thermal collector and the photo-thermal heater are connected to the first loop in parallel through a second loop; the air expansion machine is in fluid communication with a fluid outlet of the photo-thermal heater; the bypass air blower is connected to the air expansion machine in series, and the bypass air blower is in fluid communication with a fluid outlet of the air expansion machine. The heat and energy storage system can have the capacity of being rapidly started at any time and responding to a scheduling instruction, the dynamic response characteristic of the system is greatly improved, the reliability and stability of the system are improved, the energy efficiency of the system is improved, the operation cost is reduced, dependence on traditional energy is reduced, and therefore greenhouse gas emission is reduced.

Description

Technical Field

[0001] The invention relates to the field of energy storage, and provides an energy storage and heat storage system and an energy storage and heat storage method. Background Art

[0002] Storing electrical energy is one of the key technologies for optimizing the energy structure and improving the efficiency of power grid operation. Traditional compressed air energy storage systems achieve the conversion and storage of electrical energy by storing electrical energy in the form of air when the power system load is low, and releasing it to generate electricity again when the load is peak. However, the system relies on the co-combustion of natural gas to improve the efficiency of expansion work, which not only increases the system's dependence on natural gas, but also brings about the environmental problem of secondary carbon emissions.

[0003] To this end, an adiabatic compressed air energy storage system has been proposed as an optimization solution for traditional compressed air energy storage systems. By adopting a large pressure ratio quasi-adiabatic compression process, the air reaches a high temperature state during the compression process and stores its high-grade compressed heat energy, which is used to heat the expander intake air, replacing the natural gas combustion heating process, thereby eliminating dependence on natural gas and reducing secondary carbon emissions.

[0004] Although adiabatic compressed air energy storage systems have made significant progress in reducing natural gas dependence and carbon emissions, the limitations of their rapid start-up characteristics have become an important constraint on their regulatory role when they participate in power system regulation as energy storage systems. Especially in terms of response scheduling time, the system is difficult to start quickly due to the influence of large-scale time processes such as structural heating, fluid transmission and heat exchange, which in turn affects its effective regulation of the power system. Summary of the invention

[0005] The embodiment of the present invention provides an energy storage and heat storage system to solve the defect that the energy storage and heat storage system in the related art is difficult to start quickly.

[0006] The invention also provides an energy and heat storage method.

[0007] A first aspect of the present invention provides an energy storage and heat storage system, comprising: Air compressor; a heat storage heat exchanger, fluidly connected to the air compressor; a recuperator connected in parallel to the heat storage exchanger via a first circuit; Solar thermal collectors; A photothermal heater, fluidly connected to the photothermal collector, the photothermal collector and the photothermal heater are connected in parallel to the first circuit via a second circuit; an air expander, wherein the air expander is fluidically connected to a fluid outlet of the photothermal heater; A bypass blower is connected in series with the air expander and the bypass blower is fluidically connected to a fluid outlet of the air expander.

[0008] According to one embodiment of the present invention, a compression cold accumulator and a compression heat accumulator are connected in series on the first circuit, the compression cold accumulator is connected to the fluid outlet of the recuperator, and the compression heat accumulator is connected to the fluid outlet of the heat storage exchanger.

[0009] According to one embodiment of the present invention, a gas storage reservoir is also connected in parallel to the first circuit, and a gas-liquid separator is connected between the gas storage reservoir and the heat storage heat exchanger.

[0010] According to one embodiment of the present invention, the temperature of the heat storage medium in the compression heat accumulator ranges from 80 to 300 degrees Celsius.

[0011] According to one embodiment of the present invention, a photothermal cold storage device and a photothermal heat storage device are connected in series between the photothermal collector and the photothermal heater, the photothermal cold storage device is connected to the fluid outlet of the photothermal heater, and the photothermal heat storage device is connected to the fluid outlet of the photothermal collector.

[0012] According to one embodiment of the present invention, a branch is connected in parallel to the second loop, a first end of the branch is fluidically connected between the photothermal collector and the photothermal heat storage device, and a second end of the branch is fluidically connected between the photothermal heat storage device and the photothermal heater; When the solar thermal collector is in operation, part of the heat storage medium flowing out of the solar thermal collector flows into the solar thermal heater via the branch line.

[0013] According to one embodiment of the present invention, the temperature of the heat storage medium in the photothermal heat storage device is at least 200 degrees Celsius.

[0014] A second aspect of the present invention provides an energy storage and heat storage method of the energy storage and heat storage system as described above, comprising: During the electric energy input process, the ambient air is compressed by the air compressor and heat is exchanged with the low-temperature heat storage medium through the heat storage heat exchanger, and the low-temperature heat storage medium absorbs heat in the heat storage heat exchanger and stores it in the compression heat storage; During the solar thermal input process, the solar thermal collector receives solar radiation to heat the low-temperature thermal storage medium transported by the solar thermal cold storage device, and the warm thermal storage medium is heated and stored in the solar thermal heat storage device; During the energy release process, the compressed air enters the regenerative heat exchanger to exchange heat with the high-temperature heat storage medium, and after being heated, enters the photothermal heater to exchange heat with the high-temperature heat storage medium. The compressed air heated again enters the air expander to expand and do work, and drives the generator to output electrical energy. The heat storage medium releases heat and cools down in the regenerative heat exchanger and the photothermal heater, and is stored in the compression cold storage device and the photothermal cold storage device respectively. In the non-energy release process, the bypass blower drives the air to circulate in the loop formed by the bypass blower, the heat exchanger, the solar thermal heater and the air expander; if the solar thermal collector collects solar energy, part of the heated high-temperature heat storage medium directly enters the solar thermal heater; if the solar thermal collector is in a non-solar energy collection state, the high-temperature heat storage medium in the solar thermal storage enters the solar thermal heater to heat the circulating air.

[0015] According to the heat storage and energy storage system provided by the embodiment of the first aspect of the present invention, by recovering the heat generated by the air compressor and using solar energy for photothermal conversion, the energy storage and heat storage system provided by the present invention can expand and generate electricity at a higher temperature, significantly improving the efficiency of energy utilization. At the same time, by setting a bypass blower to put the air expander and the auxiliary system in a hot standby state, it can have the ability to quickly start and respond to scheduling instructions at any time, so that the dynamic response characteristics of the system are greatly improved. The improvement of system energy efficiency and response characteristics will help to further improve the energy conservation and emission reduction capabilities of the entire energy system and reduce the operating costs of the energy system. Since the system includes multiple parallel heat energy conversion and storage units (such as heat storage heat exchangers, heat recovery heat exchangers, photothermal collectors and photothermal heaters), the production and consumption of heat energy can be flexibly adjusted according to actual needs, which helps to cope with different weather conditions and changes in energy demand. By integrating photothermal collectors and photothermal heaters, the present invention also promotes the use of renewable energy (such as solar energy), which not only helps to reduce dependence on traditional energy, but also helps to reduce greenhouse gas emissions and promote sustainable development. Since the system contains multiple heat sources and thermal energy storage units, the system can still maintain stable operation when some heat sources fail or the energy supply is insufficient, thereby improving the reliability and stability of the system.

[0016] According to the energy storage and heat storage method provided by the embodiment of the second aspect of the present invention, the two input modes of electric energy and photothermal energy are combined to realize diversified energy storage. Through the design of the heat storage heat exchanger and the photothermal collector, efficient heat energy conversion and storage are realized. In the energy release process, the efficient output of electric energy is realized through multi-stage heat exchange and the work of the air expander. This method can flexibly adjust the energy storage and energy release strategies according to the lighting conditions and power demand. In the non-energy release process, the hot standby state of the system power generation system is ensured by the coordinated work of the bypass blower, the photothermal collector and the heat storage device, and the rapid response capability of the system is improved. This method uses solar energy as the main energy input, reducing dependence on fossil fuels. Through efficient heat energy conversion and storage, energy consumption and emissions are reduced, which is in line with the concept of sustainable development. This method reduces energy costs by improving energy utilization efficiency and system flexibility. The energy storage and heat storage system can be used as a supplementary energy source for the power grid, improve the stability and reliability of the power grid, and provide new business opportunities for the power market. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic structural diagram of the energy storage and heat storage system provided by the present invention.

[0019] Figure 2 It is a schematic flow chart of the energy storage and heat storage method provided by the present invention.

[0020] Reference numerals: 100. Air compressor; 102. Thermal storage heat exchanger; 104. Regenerative heat exchanger; 106. Solar thermal collector; 108. Solar thermal heater; 110. Compression cold storage; 112. Compression heat storage; 114. Gas storage; 116. Gas-liquid separator; 118. Solar thermal cold storage; 120. Solar thermal storage; 122. Air expander; 124. Bypass blower. DETAILED DESCRIPTION

[0021] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0022] like Figure 1 As shown, the first embodiment of the present invention provides an energy storage and heat storage system, comprising: Air compressor 100; The heat storage heat exchanger 102 is fluidically connected to the air compressor 100; The regenerative heat exchanger 104 is connected in parallel to the heat storage heat exchanger 102 through the first loop; Photothermal collector 106; The photothermal heater 108 is fluidically connected to the photothermal collector 106, and the photothermal collector 106 and the photothermal heater 108 are connected in parallel to the first circuit through a second circuit; An air expander 122, wherein the air expander 122 is fluidically connected to a fluid outlet of the photothermal heater 108; The bypass blower 124 is connected in series to the air expander 122 and the bypass blower 124 is fluidically connected to the fluid outlet of the air expander 122 .

[0023] According to the heat storage and energy storage system provided by the embodiment of the first aspect of the present invention, by recovering the heat generated by the air compressor 100 and using solar energy for photothermal conversion, the energy storage and heat storage system provided by the present invention can expand and generate electricity at a higher temperature, significantly improving the efficiency of energy utilization. At the same time, by setting the bypass blower 124, the air expander 122 and the auxiliary system are in a hot standby state, so that they can have the ability to quickly start and respond to scheduling instructions at any time, so that the dynamic response characteristics of the system are greatly improved. The improvement of system energy efficiency and response characteristics will help to further improve the energy-saving and emission reduction capabilities of the entire energy system and reduce the operating costs of the energy system. Since the system includes multiple parallel heat energy conversion and storage units (such as heat storage heat exchanger 102, heat recovery heat exchanger 104, photothermal collector 106 and photothermal heater 108), the production and consumption of heat energy can be flexibly adjusted according to actual needs, which helps to cope with different weather conditions and changes in energy demand. By integrating the photothermal collector 106 and the photothermal heater 108, the present invention also promotes the use of renewable energy (such as solar energy), which not only helps to reduce dependence on traditional energy, but also helps to reduce greenhouse gas emissions and promote sustainable development. Since the system includes multiple heat sources and thermal energy storage units, the system can still maintain stable operation when some heat sources fail or energy supply is insufficient, thereby improving the reliability and stability of the system.

[0024] Please continue to see Figure 1 As the core power device of the system, the air compressor 100 is used to compress gas (such as air), which generates heat during the process. This heat is an important source of heat recovery and utilization of the system.

[0025] The heat storage heat exchanger 102 is fluidically connected to the air compressor 100, and is used to capture the heat generated by the air compressor 100 during the gas compression process and transfer it to the working fluid (such as water, oil, etc.), thereby realizing the storage of thermal energy. The heat storage heat exchanger 102 is designed with an efficient heat exchange structure to ensure that as much heat as possible is recovered.

[0026] The heat exchanger 104 is connected in parallel to the heat storage heat exchanger 102 through the first loop to form a heat energy circulation loop. When necessary, the heat exchanger 104 can release the stored heat energy back to the system to preheat the gas entering the air compressor 100, thereby improving the overall efficiency of the system.

[0027] As another heat source, the photothermal collector 106 utilizes solar energy to convert light energy into heat energy. It is usually composed of one or more heat absorbing panels that can absorb sunlight and convert it into heat energy.

[0028] The CTH heater 108 is fluidically connected to the CTH collector 106 for further heating the heat energy collected by the CTH collector 106. The CTH heater 108 and the CTH collector 106 are connected in parallel to the first loop through the second loop, which means they can work independently or in coordination to provide additional heat energy according to system requirements.

[0029] According to one embodiment of the present invention, a compression cold accumulator 110 and a compression heat accumulator 112 are connected in series in the first circuit. The compression cold accumulator 110 is connected to the fluid outlet of the heat recovery heat exchanger 104 , and the compression heat accumulator 112 is connected to the fluid outlet of the heat storage heat exchanger 102 .

[0030] The energy storage and heat storage system has been further optimized and enhanced. In particular, in the first loop, the present embodiment connects the compression cold storage device 110 and the compression heat storage device 112 in series, and the two devices are connected to the fluid outlets of the heat recovery heat exchanger 104 and the heat storage heat exchanger 102, respectively. The following is a detailed description of the technical solution: The compression cold storage device 110 is connected in series after the fluid outlet of the regenerative heat exchanger 104. When the system needs to cool or adjust the temperature, the compression cold storage device 110 can absorb and store cold energy using the cold storage medium (such as phase change material, refrigerant, etc.) inside it. In this way, when necessary, the compression cold storage device 110 can release cold energy to reduce the system temperature or provide a cooling effect.

[0031] The compression heat accumulator 112 corresponds to the compression cold accumulator 110, and is connected in series after the fluid outlet of the heat storage heat exchanger 102. It uses a heat storage medium (such as molten salt, paraffin, etc.) to store the heat transferred from the heat storage heat exchanger 102. When needed, the compression heat accumulator 112 can release the stored heat energy to supplement the system heat energy or meet other heat energy needs.

[0032] By connecting the compression cold accumulator 110 and the compression heat accumulator 112 in series on the first loop, this embodiment achieves more precise control of the system temperature and heat energy. The two devices can work independently or in conjunction with each other according to system requirements to adjust the overall temperature and heat energy balance of the system.

[0033] By introducing the compression cold accumulator 110 and the compression heat accumulator 112, the system is able to utilize and store cold and heat energy more efficiently. This helps to reduce energy waste and improve the overall energy efficiency of the system. Since the system can store and release cold and heat energy at the same time, the temperature and heat output of the system can be flexibly adjusted according to actual needs. This helps to cope with changes in different seasons, weather conditions and energy needs. By integrating the compression cold accumulator 110 and the compression heat accumulator 112, the system is able to manage energy more intelligently. For example, at night or during periods of low electricity prices, the system can give priority to using electricity for cold or heat storage operations to reduce operating costs. Under certain extreme weather conditions (such as high temperatures in summer or severe cold in winter), the system can maintain a stable operating state by releasing the stored cold and heat energy. This helps to improve the reliability and stability of the system.

[0034] According to one embodiment of the present invention, a gas storage reservoir 114 is connected in parallel to the first circuit, and a gas-liquid separator 116 is connected between the gas storage reservoir 114 and the heat storage heat exchanger 102 .

[0035] A gas storage reservoir 114 is also connected in parallel to the first circuit of the energy storage and heat storage system. This design is intended to further enhance the energy storage capacity and flexibility of the system. A gas-liquid separator 116 is connected between the gas storage reservoir 114 and the heat storage heat exchanger 102 to ensure that the gas entering the gas storage reservoir 114 is pure and does not contain liquid components. The following is a detailed description of the technical solution: The gas storage reservoir 114 is a device for storing compressed gas, which is connected in parallel to the first circuit and can exchange gas with the heat storage heat exchanger 102. In the system, the gas storage reservoir 114 can be used as an additional energy storage unit to release or absorb gas when needed, thereby adjusting the pressure and energy state of the system.

[0036] The gas-liquid separator 116 is connected between the gas storage 114 and the heat storage heat exchanger 102. Its main function is to ensure that the gas flowing out of the heat storage heat exchanger 102 has been separated and the liquid components have been removed before entering the gas storage 114. This helps to prevent problems such as pressure increase or equipment damage caused by the accumulation of liquid substances inside the gas storage 114.

[0037] In this embodiment, the introduction of the gas storage 114 and the gas-liquid separator 116 does not change the original basic structure and function of the system. They work together with other components in the system (such as the air compressor 100, the heat storage heat exchanger 102, the heat recovery heat exchanger 104, etc.) to achieve energy storage, conversion and release.

[0038] The introduction of the gas storage reservoir 114 enables the system to store more compressed gas, thereby improving the energy storage efficiency of the system. When needed, the gas storage reservoir 114 can release the stored gas to provide additional energy support for the system. Since the gas storage reservoir 114 can serve as an independent energy storage unit, the system can flexibly adjust its working state according to actual needs. For example, during peak hours or when energy demand suddenly increases, the system can quickly release gas from the gas storage reservoir 114 to meet demand. The setting of the gas-liquid separator 116 ensures that the gas entering the gas storage reservoir 114 is pure and does not contain liquid components. This helps to prevent safety hazards caused by the accumulation of liquid substances and improves the overall safety and reliability of the system. By introducing the gas storage reservoir 114 and the gas-liquid separator 116, the system can manage energy more intelligently. For example, during periods when energy prices are low or supply is sufficient, the system can give priority to using electrical energy for gas compression and storage operations; while during periods when energy prices are high or supply is tight, gas can be released from the gas storage reservoir 114 to meet demand.

[0039] According to one embodiment of the present invention, the temperature of the heat storage medium in the compression heat accumulator 112 ranges from 80 to 300 degrees Celsius.

[0040] In one embodiment of the present invention, the temperature of the heat storage medium in the compressed heat accumulator 112 is controlled within a range of 80 to 300 degrees Celsius. This technical solution is designed to optimize the performance of the heat accumulator, improve energy storage efficiency, and ensure stable operation of the system. The following is a detailed description of the technical solution: The heat storage medium is a key component in the compression heat accumulator 112, which is used to store and release thermal energy. In this embodiment, the selection of the heat storage medium should satisfy the requirement of having good thermal stability and thermal conductivity within the range of 80 to 300 degrees Celsius.

[0041] Common heat storage media include water, brine, thermal oil, etc. These media can maintain stable physical and chemical properties within a specified temperature range and have high heat capacity and thermal conductivity.

[0042] In order to ensure that the temperature of the thermal storage medium is maintained within the range of 80 to 300 degrees Celsius, the system is equipped with advanced temperature control devices. These devices are able to monitor the temperature of the thermal storage medium in real time and adjust it as needed.

[0043] The temperature control device includes a heating element, a cooling element, a temperature sensor, a controller, etc. When the temperature is lower than the set range, the heating element will start to increase the temperature; when the temperature is higher than the set range, the cooling element will start to lower the temperature.

[0044] In order to reduce heat loss and keep the temperature inside the heat accumulator stable, the shell of the heat accumulator adopts high-efficiency thermal insulation materials. These materials can effectively block the input of external heat and the output of internal heat.

[0045] In addition, the inlet and outlet pipes of the heat accumulator are also insulated to ensure that heat loss is minimized during the flow of the medium.

[0046] Controlling the temperature of the thermal storage medium within the range of 80 to 300 degrees Celsius can ensure that the thermal storage works in the best condition. This helps to improve energy storage efficiency and enables the system to store and release thermal energy more efficiently. Stable thermal storage medium temperature helps to reduce thermal stress and heat loss in the system, thereby extending the service life of the system and improving overall performance. In addition, this can also reduce the maintenance cost and failure rate of the system. By precisely controlling the temperature of the thermal storage medium, the system can respond more quickly to changes in external conditions. This helps to enhance the flexibility and adaptability of the system, enabling it to better meet the needs of various application scenarios. The optimized thermal storage medium temperature range helps to improve energy utilization efficiency. When releasing thermal energy, the system is able to make more full use of the stored energy, thereby reducing dependence on and consumption of external energy.

[0047] According to one embodiment of the present invention, a solar thermal cold storage device 118 and a solar thermal heat storage device 120 are connected in series between the solar thermal collector 106 and the solar thermal heater 108. The solar thermal cold storage device 118 is connected to the fluid outlet of the solar thermal heater 108, and the solar thermal heat storage device 120 is connected to the fluid outlet of the solar thermal collector 106.

[0048] In one embodiment of the present invention, a solar thermal cold storage device 118 and a solar thermal heat storage device 120 are creatively connected in series between the solar thermal collector 106 and the solar thermal heater 108. This unique design aims to more effectively utilize solar energy and improve the flexibility and efficiency of the energy system. The following is a detailed description of the technical solution: The solar thermal collector 106 is the starting point of the system and is responsible for collecting solar radiation and converting it into thermal energy. It usually uses efficient thermal collection materials and technologies to maximize the absorption of solar energy.

[0049] The photothermal heat storage tank 120 is connected to the fluid outlet of the photothermal heat collector 106. Its main function is to store the thermal energy collected from the photothermal heat collector 106. The heat storage tank is usually made of materials with high thermal conductivity and high heat capacity to ensure effective storage and long-term retention of thermal energy.

[0050] The photothermal heater 108 is a heat energy conversion device in the system, which is responsible for converting the stored thermal energy into heat energy that can be used for heating, power generation or other thermal energy applications. It is usually connected to a heat storage device so that heat energy can be extracted from the heat storage device when needed.

[0051] The photothermal cold storage device 118 is connected to the fluid outlet of the photothermal heater 108. This design is an innovation of the present invention, which allows the system to convert excess heat energy into cold energy and store it when heat energy is excessive or not needed. Phase change materials or other high-efficiency cold storage technologies are usually used inside the cold storage device to ensure effective storage and long-term retention of cold energy.

[0052] On sunny days with sufficient solar energy, the solar thermal collector 106 collects solar energy and converts it into thermal energy, which is then stored in the solar thermal storage tank 120 .

[0053] When thermal energy is needed, the photothermal heater 108 extracts thermal energy from the thermal storage tank and converts it into thermal energy that can be used for various applications.

[0054] If the heat energy generated by the system is excessive or not needed, the solar thermal heater 108 transfers the excess heat energy to the solar thermal cold storage device 118, which converts it into cold energy and stores it.

[0055] When cold energy is needed (such as in summer or in specific application scenarios), the solar thermal cold storage device 118 can release the stored cold energy to meet the cooling needs of the system.

[0056] By connecting the solar thermal heat storage device 120 and the solar thermal cold storage device 118 in series, the system can make more efficient use of solar energy. When there is excess heat energy, the system can convert the excess heat energy into cold energy and store it for later use. This helps to reduce energy waste and improve overall energy efficiency. This design enables the system to meet both heating and cooling needs. In winter or when heating is required, the system can rely on the solar thermal collector 106 and the solar thermal heat storage device 120 to provide heat energy; in summer or when cooling is required, the system can rely on the solar thermal cold storage device 118 to provide cold energy. This flexibility enables the system to be more widely used in various scenarios and needs. By precisely controlling the working states of the solar thermal collector 106, the solar thermal heat storage device 120, the solar thermal heater 108, and the solar thermal cold storage device 118, the system can achieve optimal energy management. For example, when solar energy is sufficient, the system can give priority to using solar energy and store excess heat energy; when solar energy is insufficient, it can rely on stored heat or cold energy to meet demand. This optimized management helps to reduce energy costs and improve the economy of the system. This technical solution makes full use of solar energy, a renewable energy source, and helps promote the development and popularization of renewable energy. By improving the efficiency and flexibility of solar energy utilization, this technical solution provides more possibilities and options for the application of renewable energy.

[0057] According to one embodiment of the present invention, a branch is connected in parallel to the second loop, a first end of the branch is fluidly connected between the solar thermal collector 106 and the solar thermal heat storage 120, and a second end of the branch is fluidly connected between the solar thermal heat storage 120 and the solar thermal heater 108; When the solar thermal collector 106 is in operation, part of the heat storage medium flowing out of the solar thermal collector 106 flows into the solar thermal heater 108 via the branch line.

[0058] According to one embodiment of the present invention, a unique branch circuit design is connected in parallel to the second loop, which is intended to optimize the workflow of the solar thermal collector system, improve energy conversion efficiency, and ensure stable operation of the system.

[0059] The first end fluid of the branch is connected between the solar thermal collector 106 and the solar thermal heat storage device 120 , that is, the inlet of the branch is connected to the outlet of the solar thermal collector 106 , and is also connected to an intermediate node of the solar thermal heat storage device 120 .

[0060] The fluid at the second end of the branch is connected between the solar thermal heat storage tank 120 and the solar thermal heater 108 , that is, the outlet of the branch is connected to another node of the solar thermal heat storage tank 120 , and is also connected to the inlet of the solar thermal heater 108 .

[0061] When the solar thermal collector 106 operates normally, it collects solar radiation and converts it into thermal energy to heat the thermal storage medium. Part of the heated thermal storage medium will flow through the branch instead of directly entering the main storage area of ​​the solar thermal storage tank 120. These thermal storage media flowing through the branch will bypass part of the solar thermal storage tank 120 and directly enter the solar thermal heater 108. In the solar thermal heater 108, the thermal storage medium releases its thermal energy for heating, power generation or other thermal energy applications. At the same time, the remaining part of the thermal storage medium will still enter the main storage area of ​​the solar thermal storage tank 120 for later use.

[0062] The system is equipped with an intelligent control mechanism for monitoring the working status of the CSP collector 106, the CSP heat storage device 120 and the CSP heater 108. According to actual demand and system status, the control mechanism can adjust the flow rate of the thermal storage medium flowing through the branch to optimize the energy conversion efficiency and system performance.

[0063] Through the branch design, part of the heat storage medium can enter the photothermal heater 108 faster and release its heat energy. This helps to reduce the loss of energy during transmission and storage and improve energy conversion efficiency. The branch design enables the system to adjust the flow path of the heat storage medium according to actual needs. This helps the system to respond to different working environments and energy needs more flexibly. The intelligent control mechanism can monitor the status and needs of the system in real time, and adjust the flow of the heat storage medium flowing through the branch according to this information. This helps to achieve optimal energy management, reduce energy costs and improve the economy of the system. By reasonably designing the flow of the branch and controlling the working state of the system, it can be ensured that the system maintains a stable temperature and pressure during operation. This helps to extend the service life of the system and improve the overall performance.

[0064] According to one embodiment of the present invention, the temperature of the heat storage medium in the solar thermal heat storage device 120 is at least 200 degrees Celsius.

[0065] According to one embodiment of the present invention, the heat storage medium in the solar thermal heat storage device 120 is set within a specific temperature range, that is, its temperature is at least 200 degrees Celsius. This technical solution is proposed to ensure that the solar thermal heat storage device 120 can store and release thermal energy efficiently and stably, thereby improving the performance and efficiency of the entire solar thermal power generation system.

[0066] The thermal storage medium is a core component of the solar thermal storage device 120, and its selection directly affects the performance and efficiency of the thermal storage device. In this embodiment, the thermal storage medium needs to be able to remain stable at a temperature of at least 200 degrees Celsius and have good thermal conductivity and heat storage capacity.

[0067] Common heat storage media include molten salt, thermal oil, etc. These media can maintain stable physical and chemical properties at high temperatures and have high heat capacity and thermal conductivity, and are therefore suitable as heat storage media for the solar thermal storage device 120 .

[0068] The design of the solar thermal heat storage device 120 needs to take into account factors such as thermal stress, thermal expansion, and thermal conduction in a high temperature environment. In order to ensure that the heat storage device can operate stably at a temperature of at least 200 degrees Celsius, high temperature resistant materials and structures need to be used.

[0069] For example, the inner wall and outer shell of the heat accumulator can be made of high-temperature alloy or ceramic materials, which have good high-temperature resistance and thermal stability. In addition, the internal structure of the heat accumulator also needs to be optimized to improve heat conduction efficiency and heat storage capacity.

[0070] In order to ensure that the temperature of the thermal storage medium is maintained within a range of at least 200 degrees Celsius, the solar thermal storage device 120 needs to be equipped with an advanced temperature control system. The system can monitor the temperature of the thermal storage medium in real time and adjust it as needed.

[0071] The temperature control system includes a heating element, a cooling element (although the main purpose in this example is to maintain a high temperature, the cooling element can be used to prevent overheating or perform precise temperature regulation), a temperature sensor, a controller, etc. When the temperature is below the set range, the heating element will start to increase the temperature; when the temperature is too high, although it is unlikely to directly use a cooling element to reduce the temperature in this embodiment (because this is contrary to the requirement of maintaining at least 200 degrees Celsius), a stable temperature can be maintained by adjusting the power of the heating element or using other methods.

[0072] Setting the temperature of the heat storage medium at at least 200 degrees Celsius can ensure that the photothermal heat storage device 120 operates stably at high temperatures, thereby improving the energy storage efficiency. The heat storage medium at high temperatures can store more thermal energy and release it quickly when needed. High-temperature heat storage media helps to improve the overall performance of the photothermal power generation system. During the power generation process, high-temperature thermal energy can be more efficiently converted into electrical energy or other forms of energy. In addition, high-temperature heat storage media can also reduce heat loss and efficiency loss during energy conversion. By keeping the heat storage medium running stably at a temperature of at least 200 degrees Celsius, the photothermal heat storage device 120 can reduce problems such as thermal stress and thermal expansion caused by temperature changes. This helps to enhance the stability and reliability of the system and extend the service life of the system. The technical solution in this embodiment places higher requirements on the design and material selection of the photothermal heat storage device 120. In order to meet these requirements, it is necessary to continuously promote technological innovation and research and development. This will promote the further development and improvement of photothermal power generation technology.

[0073] According to one embodiment of the present invention, an air expander 122 is further included. The air expander 122 is fluidically connected to the fluid outlet of the photothermal heater 108 .

[0074] According to one embodiment of the present invention, an air expander 122 is innovatively added at the fluid outlet of the photothermal heater 108. This design aims to further utilize the thermal energy generated by the photothermal heater 108 and convert it into mechanical energy or electrical energy, thereby improving the energy conversion efficiency and practicality of the entire photothermal system.

[0075] The air expander 122 is a device driven by thermal energy, which can expand high-temperature and high-pressure gas (such as air) to do work, thereby outputting mechanical energy or driving a generator to generate electrical energy. In this embodiment, the fluid (gas or steam) heated by the photothermal heater 108 is introduced into the air expander 122. These high-temperature and high-pressure fluids expand and do work in the expander, driving the rotor of the expander to rotate. The rotation of the rotor can be used directly to drive mechanical equipment, or to generate electrical energy by connecting a generator.

[0076] The fluid outlet of the photothermal heater 108 is connected to the inlet of the air expander 122 through a pipe or other fluid connection device to ensure that the heated fluid can flow smoothly into the expander. In the working process, the photothermal collector 106 first collects solar radiation and converts it into thermal energy to heat the heat storage medium. These heated heat storage media are then sent to the photothermal heater 108, further heated and converted into high-temperature and high-pressure fluids. These high-temperature and high-pressure fluids are then introduced into the air expander 122, expand to do work and output mechanical energy or electrical energy. The expanded low-temperature and low-pressure fluid can be processed by a cooling system or other means for recycling or discharge.

[0077] In order to ensure the stable operation of the system and efficient energy conversion, an advanced control system is required to monitor and adjust the working status of each component. The control system can monitor the temperature and pressure of the photothermal heater 108, the air expander 122 and the entire system in real time and adjust them as needed. In addition, the energy conversion efficiency and system performance can be improved by optimizing the system design and parameter configuration.

[0078] By adding an air expander 122, the thermal energy generated by the photothermal heater 108 can be further utilized and converted into mechanical energy or electrical energy. This helps to improve the energy conversion efficiency of the entire photothermal system and reduce energy waste. The addition of the air expander 122 enables the photothermal system to directly output mechanical energy or electrical energy, thereby meeting more diverse energy needs. This enhances the practicality and application scope of the system. The technical solution in this embodiment puts higher requirements on the design and optimization of the photothermal system. In order to meet these requirements, it is necessary to continuously promote technological innovation and research and development. This will promote the further development and improvement of photothermal technology. By reasonably designing and optimizing the connection and work flow of system components, the system can be ensured to operate stably under high temperature and high pressure environments. This helps to improve the stability and reliability of the system and extend the service life of the system.

[0079] According to one embodiment of the present invention, a bypass blower 124 is further included. The bypass blower 124 is connected in series to the air expander 122 and the bypass blower 124 is fluidically connected to the fluid outlet of the air expander 122 .

[0080] According to one embodiment of the present invention, a bypass blower 124 is innovatively added at the fluid outlet of the air expander 122. This design is intended to further optimize the heat energy conversion and utilization process of the solar thermal system, and to use solar thermal energy to achieve long-term hot standby of the expansion power generation system, thereby improving the overall efficiency and flexibility of the system.

[0081] The bypass blower 124 is a device used to provide fluid power (such as air or gas) that can transport the fluid from one location to another.

[0082] In this embodiment, the bypass blower 124 is connected in series after the air expander 122, and its fluid inlet is connected to the fluid outlet of the air expander 122. When the air expander 122 completes the heat energy conversion and outputs the mechanical energy or electrical energy, the remaining low-temperature and low-pressure fluid (such as air or steam) will be introduced into the bypass blower 124.

[0083] The bypass blower 124 further compresses or accelerates these fluids, which may then be delivered to other system components (such as a cooling system, a reheat system, or a circulation system) for subsequent processing or utilization.

[0084] The fluid outlet of the air expander 122 is connected to the fluid inlet of the bypass blower 124 via a pipeline or other fluid connection device to ensure that the expanded fluid can flow smoothly into the bypass blower 124 .

[0085] In the working process, the fluid heated by the photothermal heater 108 is introduced into the air expander 122, expands to do work and outputs mechanical energy or electrical energy. The expanded low-temperature and low-pressure fluid is then sent to the bypass blower 124 for further compression or acceleration.

[0086] The treated fluid can be transported to other components for subsequent use according to system requirements, or discharged after treatment through a cooling system.

[0087] In order to ensure the stable operation of the system and efficient energy conversion, advanced control systems are required to monitor and adjust the working status of each component.

[0088] The control system can monitor parameters such as the temperature and pressure of the air expander 122, the bypass blower 124 and the entire system in real time, and make adjustments as needed.

[0089] By optimizing the system design and parameter configuration, the energy conversion efficiency and system performance can be further improved. For example, the speed and flow rate of the bypass blower 124 can be adjusted according to actual needs to match the output of the air expander 122 and the overall needs of the system.

[0090] The addition of the bypass blower 124 enables the expanded low-temperature and low-pressure fluid to be further utilized. By compressing or accelerating it and then delivering it to other system components, the energy utilization efficiency can be further improved and energy waste can be reduced. The design of the bypass blower 124 enables the system to be flexibly adjusted according to actual needs. For example, when a higher pressure fluid is required, the speed of the bypass blower 124 can be increased; when a lower temperature fluid is required, it can be achieved by adjusting the flow rate of the bypass blower 124 and the parameters of the cooling system. By connecting the bypass blower 124 in series after the air expander 122, the heat energy conversion process can be further optimized. The mechanical energy or electrical energy output by the expander can be directly used to drive other equipment or generate electricity, and the remaining fluid can be subsequently processed or utilized by the bypass blower 124, thereby maximizing the utilization of heat energy. The design of the bypass blower 124 enables the system to operate stably under various working conditions. By properly adjusting the operating parameters of the bypass blower 124 and coordinating with other components, it is possible to ensure that the system maintains stable performance and reliability in a high temperature and high pressure environment.

[0091] like Figure 2 As shown, the second aspect of the present invention provides an energy storage and heat storage method of the energy storage and heat storage system as described above, comprising: Step 10, during the power input process, the ambient air is compressed by the air compressor, and heat is exchanged with the low-temperature heat storage medium through the heat storage heat exchanger 102, and the low-temperature heat storage medium absorbs heat in the heat storage heat exchanger 102 and stores it in the compression heat storage 112; Step 20, during the solar heat input process, the solar heat collector 106 receives solar radiation to heat the low-temperature heat storage medium transported by the solar heat cold storage device 118, and the warm heat storage medium is heated and stored in the solar heat storage device 120; Step 30, during the energy release process, the compressed air enters the regenerative heat exchanger 104 to exchange heat with the high-temperature heat storage medium, and after being heated, enters the photothermal heater 108 to exchange heat with the high-temperature heat storage medium. The compressed air that has been heated again enters the air expander 122 to expand and do work, and drives the generator to output electrical energy. The heat storage medium releases heat and cools down in the regenerative heat exchanger 104 and the photothermal heater 108, and is stored in the compression cold storage 110 and the photothermal cold storage 118 respectively. Step 40, in the non-energy release process, the bypass blower 124 drives the air to circulate in the loop formed by the bypass blower 124, the heat exchanger 104, the solar thermal heater 108 and the air expander 122; if the solar thermal collector 106 collects solar energy, part of the heated high-temperature heat storage medium directly enters the solar thermal heater 108; if the solar thermal collector 106 is in a non-solar energy collection state, the high-temperature heat storage medium in the solar thermal storage 120 enters the solar thermal heater 108 to heat the circulating air.

[0092] According to the energy storage and heat storage method provided by the embodiment of the second aspect of the present invention, the two input modes of electric energy and photothermal energy are combined to realize diversified energy storage. Through the design of the heat storage heat exchanger 102 and the photothermal collector 106, efficient heat energy conversion and storage are realized. In the energy release process, the efficient output of electric energy is realized through multi-stage heat exchange and the work of the air expander 122. This method can flexibly adjust the energy storage and energy release strategies according to the lighting conditions and power demand. In the non-energy release process, the hot standby state of the system power generation system is ensured by the coordinated work of the bypass blower 124, the photothermal collector 106 and the heat storage, and the rapid response capability of the system is improved. This method uses solar energy as the main energy input, reducing dependence on fossil fuels. Through efficient heat energy conversion and storage, energy consumption and emissions are reduced, which is in line with the concept of sustainable development. This method reduces energy costs by improving energy utilization efficiency and system flexibility. The energy storage and heat storage system can be used as a supplementary energy source for the power grid, improve the stability and reliability of the power grid, and provide new business opportunities for the power market.

[0093] The second aspect of the present invention provides an energy storage and heat storage method for an energy storage and heat storage system. The method combines the two modes of electrical energy input and photothermal input to achieve efficient storage and release of energy.

[0094] Energy storage during power input: Use an air compressor to compress the ambient air.

[0095] The compressed air exchanges heat with the low-temperature heat storage medium through the heat storage heat exchanger 102 .

[0096] The low temperature heat storage medium absorbs the heat of the compressed air in the heat storage heat exchanger 102 and stores the heat in the compression heat accumulator 112 for subsequent use.

[0097] Energy storage during photothermal input: The solar thermal collector 106 receives solar radiation and converts it into thermal energy.

[0098] The low-temperature heat storage medium transported by the solar thermal cold storage device 118 is heated, and the heated heat storage medium is stored in the solar thermal heat storage device 120 to store solar thermal energy.

[0099] Energy release process: The compressed air first enters the heat recovery heat exchanger 104 to exchange heat with the high-temperature heat storage medium, and then enters the photothermal heater 108 after being heated.

[0100] In the photothermal heater 108 , the compressed air again exchanges heat with the high-temperature heat storage medium, and its temperature is further increased.

[0101] The heated compressed air enters the air expander 122, expands to do work, and drives the generator to output electrical energy.

[0102] After the heat storage medium releases heat and cools down in the regenerative heat exchanger 104 and the photothermal heater 108 , it is stored in the compression cold storage device 110 and the photothermal cold storage device 118 , respectively, for next use.

[0103] Energy management in non-energetic processes: The bypass blower 124 drives the air to circulate in the loop formed by the bypass blower 124, the regenerative heat exchanger 104, the photothermal heater 108, and the air expander 122; If the solar thermal collector 106 is collecting solar energy, part of the heated high-temperature heat storage medium directly enters the solar thermal heater 108 to heat the circulating air to maintain the thermal balance of the system.

[0104] If the solar thermal collector 106 is in a non-solar energy collection state (such as at night or on a rainy day), the high-temperature heat storage medium in the solar thermal heat storage tank 120 is sent to the solar thermal heater 108 to continue heating the circulating air to ensure the continuous operation of the system.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An energy storage and heat storage system, characterized in that: include: Air compressor (100); A heat storage heat exchanger (102), fluidically connected to the air compressor (100); A recuperator (104) connected in parallel to the heat storage exchanger (102) via a first loop; Photothermal collector (106); A photothermal heater (108) is fluidically connected to the photothermal collector (106); the photothermal collector (106) and the photothermal heater (108) are connected in parallel to the first circuit via a second circuit; An air expander (122), wherein the air expander (122) is fluidically connected to a fluid outlet of the photothermal heater (108); A bypass blower (124) is connected in series to the air expander (122) and the bypass blower (124) is fluidically connected to a fluid outlet of the air expander (122).

2. The energy storage and heat storage system according to claim 1, characterized in that: A compression cold accumulator (110) and a compression heat accumulator (112) are connected in series on the first circuit; the compression cold accumulator (110) is connected to the fluid outlet of the regenerative heat exchanger (104), and the compression heat accumulator (112) is connected to the fluid outlet of the regenerative heat exchanger (102).

3. The energy storage and heat storage system according to claim 2, characterized in that: A gas storage reservoir (114) is also connected in parallel to the first loop, and a gas-liquid separator (116) is connected between the gas storage reservoir (114) and the heat storage heat exchanger (102).

4. The energy storage and heat storage system according to claim 2, characterized in that: The temperature of the heat storage medium in the compression heat accumulator (112) ranges from 80 to 300 degrees Celsius.

5. The energy storage and heat storage system according to claim 1, characterized in that: A photothermal cold storage device (118) and a photothermal heat storage device (120) are connected in series between the photothermal collector (106) and the photothermal heater (108); the photothermal cold storage device (118) is connected to the fluid outlet of the photothermal heater (108), and the photothermal heat storage device (120) is connected to the fluid outlet of the photothermal collector (106).

6. The energy storage and heat storage system according to claim 5, characterized in that: A branch is connected in parallel to the second loop, a first end of the branch is fluidically connected between the photothermal collector (106) and the photothermal heat storage device (120), and a second end of the branch is fluidically connected between the photothermal heat storage device (120) and the photothermal heater (108); When the photothermal collector (106) is in operation, part of the heat storage medium flowing out of the photothermal collector (106) flows into the photothermal heater (108) via the branch line.

7. The energy storage and heat storage system according to claim 5, characterized in that: The temperature of the heat storage medium in the photothermal heat storage device (120) is at least 200 degrees Celsius.

8. An energy storage and heat storage method for an energy storage and heat storage system according to any one of claims 1 to 7, characterized in that: include: During the electric energy input process, the ambient air is compressed by the air compressor and heat is exchanged with the low-temperature heat storage medium through the heat storage heat exchanger (102), and the low-temperature heat storage medium absorbs heat in the heat storage heat exchanger (102) and stores it in the compression heat storage (112); During the photothermal input process, the photothermal collector (106) receives solar radiation to heat the low-temperature heat storage medium transported by the photothermal cold storage device (118), and the warm heat storage medium is heated and stored in the photothermal heat storage device (120); During the energy release process, the compressed air enters the regenerative heat exchanger (104) to exchange heat with the high-temperature heat storage medium, and after being heated, enters the photothermal heater (108) to exchange heat with the high-temperature heat storage medium. The compressed air, after being heated again, enters the air expander (122) to expand and perform work, and drives the generator to output electrical energy. The heat storage medium releases heat and cools down in the regenerative heat exchanger (104) and the photothermal heater (108), and is then stored in the compression cold storage device (110) and the photothermal cold storage device (118), respectively. In the non-energy release process, the bypass blower (124) drives the air to circulate in the loop formed by the bypass blower (124), the heat exchanger (104), the photothermal heater (108) and the air expander (122); if the photothermal collector (106) collects solar energy, part of the heated high-temperature heat storage medium directly enters the photothermal heater (108); if the photothermal collector (106) is in a non-solar energy collection state, the high-temperature heat storage medium in the photothermal heat storage (120) enters the photothermal heater (108) to heat the circulating air.

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