Novel photo-thermal compressed air power generation system and method

Abstract

The invention discloses a novel photo-thermal compressed air power generation technology which comprises the following steps: a condensation module is used for tracking the sun through a heliostat and reflecting and focusing sunlight to a heat absorber, and the heat absorber converts solar energy into heat energy to heat compressed air; the heat storage and structure integration module is used for storing compressed air into the heat absorption tower, storing heat energy of high-temperature compressed air and driving a compressed air turbine to rotate based on the heat energy, and the turbine is linked with a generator to generate power and discharge low-temperature and low-pressure air; the heat recovery circulation module is used for driving a multi-stage compressor to compress air through a motor, absorbing heat released in the compression process through a water-gas heat exchanger, storing the heat in a hot water tank, preheating the compressed air through a heat pump and a heater and then conveying the compressed air back to a heat absorber to be heated, and a heat energy closed loop is formed. According to the invention, the power generation efficiency is improved, the initial investment and the kilowatt-hour cost are reduced, and the problems of high initial investment and high kilowatt-hour cost of tower-type photo-thermal power generation are solved.

Description

Technical Field

[0001] This invention relates to the field of new energy cross-technology, specifically to a novel solar thermal compressed air power generation system and method. Background Technology

[0002] Existing tower-type concentrated solar power (CSP) technology focuses sunlight onto a central heat-absorbing tower using a large-scale heliostat array, converting solar energy into thermal energy. Its core process includes five key steps: a concentrating system to track and reflect sunlight; a heat-absorbing system to convert solar energy into thermal energy via a heat absorber; a thermal storage system to address the intermittent nature of sunlight; a heat exchange system to exchange heat between molten salt and water to generate steam; and a steam turbine power generation system to drive a steam turbine to generate electricity. A typical structure is shown below. Figure 2 As shown.

[0003] Despite the maturity of existing technologies, solar thermal power generation faces significant drawbacks, primarily manifested in high cost, low efficiency, and system complexity. The initial investment for tower-type concentrated solar power (CSP) is as high as 150-170 million RMB / kW, mainly due to the expensive cost of heliostats and molten salt thermal storage systems (accounting for 40%-50% and 20%-25% of the cost, respectively), as well as the maintenance difficulty of molten salt systems (such as hot molten salt tanks, pumps, and anti-condensation protection systems). Steam power generation systems generally have an efficiency of 40%-45%, far lower than that of compressed air energy storage, resulting in a lack of market competitiveness in terms of cost per kilowatt-hour compared to coal-fired power. Furthermore, system complexity increases reliability issues: molten salt is prone to solidification requiring additional protection; the heat exchange process is cumbersome (solar energy - molten salt thermal energy - steam - electricity), resulting in significant energy loss; and the steam system relies on cooling towers, exacerbating water resource and site requirements. These disadvantages stem from the inefficiency of core components, such as the high cost of molten salt thermal storage and the low efficiency of steam turbines, limiting the promotion and economic viability of CSP. Summary of the Invention

[0004] The purpose of this invention is to provide a novel solar thermal compressed air power generation system and method. This invention innovatively combines the advantages of tower solar thermal power generation and compressed air energy storage technology, replacing the steam power generation system with a compressed air power generation system. This improves work efficiency and directly converts solar energy into compressed air heat energy and then into electricity, increasing efficiency and eliminating the need for a cooling tower. The heat storage system uses magnesia bricks instead of molten salt. Magnesia bricks are high-temperature resistant and also function as a structural material for heat-absorbing towers. Through staggered stacking, air channels are left, simplifying the system and eliminating the need for molten salt tanks, pumps, and anti-condensation protection systems, significantly reducing initial investment. Simultaneously, the optimized heat exchange process eliminates the molten salt stage. The system generates electricity by storing heat during sunlight and continues to operate using stored heat when there is no sunlight, thus significantly reducing initial investment and comprehensively improving economy and reliability.

[0005] To achieve this objective, the present invention provides a novel solar thermal compressed air power generation system, comprising: The concentrating module is used to track the sun via a heliostat and reflect and focus sunlight to a heat absorber, which converts solar energy into thermal energy and heats low-temperature, high-pressure air to obtain high-temperature, high-pressure air. The thermal storage and structural integration module is used to store high-temperature and high-pressure air into the heat absorption tower. The thermal energy of the high-temperature and high-pressure air drives the compressed air turbine to rotate. The compressed air turbine is linked to a generator to generate electricity. The generator generates electricity and outputs low-temperature and low-pressure air from the compressed air turbine. The heat recovery circulation module is used to compress the low-temperature, low-pressure air into low-temperature, high-pressure air by driving a multi-stage compressor with a motor. The low-temperature, high-pressure air is then delivered to the heat absorber. Cold water drawn from the cold water tank is delivered to the multi-stage water-air heat exchanger by a cold water pump. The heat released during the compression process of the low-temperature, low-pressure air into low-temperature, high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is stored in a hot water tank. Hot water is drawn from the hot water tank and pressurized by a heat pump to generate high-temperature, high-pressure hot water. The high-temperature, high-pressure hot water flows into the multi-stage air-water heater, and the heat energy of the high-temperature, high-pressure hot water is incorporated into the high-temperature, high-pressure air that has passed through the multi-stage air-water heater, forming a closed-loop airflow.

[0006] Preferably, magnesium oxide bricks are used as the heat storage material in the heat absorption tower.

[0007] Preferably, the magnesium oxide bricks are stacked in an orthogonal staggered manner, with air circulation channels reserved.

[0008] Preferably, the specific method for generating electrical energy from the generator and discharging low-temperature, low-pressure air from the compressed air turbine is as follows: Based on the thermal energy and pressure potential energy of high-temperature and high-pressure air, the high-temperature and high-pressure air expands and does work in the compressed air turbine, driving the compressed air turbine blades to rotate, converting the thermal energy and pressure potential energy of the high-temperature and high-pressure air into mechanical energy, and obtaining low-temperature and low-pressure air. Compressed air turbines transmit mechanical energy through a main shaft based on the rotation of blades, while generator rotors cut magnetic field lines and convert mechanical energy into electrical energy through electromagnetic induction.

[0009] Preferably, the low-temperature, low-pressure air discharged from the compressed air turbine is connected to a multi-stage compressor.

[0010] Preferably, the low-temperature, high-pressure air output by the multi-stage compressor is heated by a heat absorber and transformed into high-temperature, high-pressure air, which is stored in the heat absorber tower. The high-temperature, high-pressure air drives the compressed air turbine to expand and do work, discharging the low-temperature, low-pressure air. The low-temperature, low-pressure air is then transmitted to the multi-stage compressor, where it is compressed into low-temperature, high-pressure air and transmitted to the heat absorber, forming a closed-loop airflow.

[0011] Preferably, solar energy is focused onto a heat absorber, where light energy is converted into heat energy to heat low-temperature, high-pressure air, resulting in high-temperature, high-pressure air which is then stored in a heat absorption tower. In a compressed air turbine, the high-temperature, high-pressure air expands and performs work, driving the blades to rotate and converting the thermal and pressure potential energy of the high-temperature, high-pressure air into mechanical energy, resulting in low-temperature, low-pressure air. The mechanical energy is transmitted to a generator via a main shaft, and the rotor cuts magnetic field lines, converting the mechanical energy into electrical energy through electromagnetic induction. The electrical energy drives a multi-stage compressor to compress the low-temperature, low-pressure air, resulting in low-temperature, high-pressure air. The heat energy released during the compression process is absorbed by cold water in a multi-stage water-air heat exchanger, generating hot water which is stored in a hot water tank. Hot water is drawn from the tank, pressurized by a heat pump, and then flows into a multi-stage air-water heater. The heat energy of the high-temperature, high-pressure hot water is transferred to the high-temperature, high-pressure air, forming a closed-loop heat energy system.

[0012] Preferably, a cold water pump delivers cold water from the cold water tank to a multi-stage water-air heat exchanger, where it absorbs the heat energy released during the compression of low-temperature, low-pressure air by a multi-stage compressor. The cold water absorbs the heat energy and heats up to generate hot water, which is then stored in a hot water tank. The hot water drawn from the hot water tank is pressurized to a high-temperature, high-pressure state by a heat pump and flows into a multi-stage air-water heater, where it releases heat energy to cool down and generate cold water. The water then flows back to the cold water tank for recycling, forming a closed-loop water cycle.

[0013] A novel method for generating electricity using solar thermal compressed air, comprising: By tracking the sun with a heliostat and reflecting and focusing sunlight onto a heat absorber, the heat absorber converts solar energy into thermal energy and heats low-temperature, high-pressure air to obtain high-temperature, high-pressure air. High-temperature and high-pressure air is stored in the heat absorption tower. The heat energy of the high-temperature and high-pressure air drives the rotation of the compressed air turbine. The compressed air turbine is linked to the generator to generate electricity. The generator generates electricity and outputs low-temperature and low-pressure air from the compressed air turbine. The low-temperature, low-pressure air is compressed into low-temperature, high-pressure air by a multi-stage compressor driven by a motor. The low-temperature, high-pressure air is then delivered to the heat absorber. Cold water drawn from a cold water tank is delivered to a multi-stage water-air heat exchanger by a cold water pump. The heat released during the compression process of the low-temperature, low-pressure air into low-temperature, high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is stored in a hot water tank. Hot water is drawn from the hot water tank and pressurized by a heat pump to generate high-temperature, high-pressure hot water. The high-temperature, high-pressure hot water flows into a multi-stage air-water heater, where the heat energy of the high-temperature, high-pressure hot water is incorporated into the high-temperature, high-pressure air that has passed through the multi-stage air-water heater, forming a closed-loop airflow.

[0014] Preferably, the heat absorption tower uses magnesium oxide bricks as the heat storage material, and the magnesium oxide bricks are stacked in an orthogonal staggered manner, with reserved air circulation channels.

[0015] The beneficial effects of this invention are as follows: This invention proposes a novel solar thermal compressed air power generation system. By replacing the traditional steam turbine power generation system with a compressed air turbine unit, this invention utilizes compressed air as the working medium, achieving a theoretical efficiency of 75% and a measured efficiency of up to 72.1%, far exceeding the 40%~45% of steam systems, resulting in an overall power generation efficiency improvement of over 50%. This effect is achieved through a multi-stage compressor and a heat recovery cycle module: the heat released during compression is absorbed and stored by cold water, and the preheated compressed air is then heated by a heat absorber, forming a closed-loop thermal energy system that maximizes energy utilization. By eliminating the molten salt thermal storage system and related equipment, magnesia bricks are used as the thermal storage material, which also serves as the structural support for the heat absorber tower. Magnesia bricks are inexpensive, and their orthogonal staggered stacking with reserved air channels simplifies the thermal storage structure and reduces initial investment. Simultaneously, the system streamlines by eliminating the heat exchange stage, directly converting solar energy into compressed air thermal energy, further reducing equipment investment and maintenance costs. By optimizing the overall system, the cost per kilowatt-hour has been reduced from 0.6-0.7 yuan / kWh for existing tower-type concentrated solar power (CSP) to 0.35-0.4 yuan / kWh. This improvement stems from the dual advantages of increased efficiency and reduced investment: the compressed air power generation system eliminates the need for a cooling tower, and the heat recovery module recovers the heat released during compression, reducing energy loss; the magnesia bricks are heat-resistant, ensuring stable system operation and avoiding the additional energy consumption associated with preheating and anti-condensation in traditional molten salt systems. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of an existing tower-type concentrated solar power (CSP) process. Figure 3 This is a schematic diagram of the tower-type solar thermal power generation process of the present invention; Figure 4 A schematic diagram of a magnesium oxide brick stacking structure; In the diagram, 1—Heliostat, 2—Absorber, 3—Absorber tower, 4—Compressed air turbine, 5—Generator, 6—Stage 1 compressor, 7—Stage 2 compressor, 8—Stage 3 compressor, 9—Stage 4 compressor, 10—Generator, 11—Cold water tank, 12—Hot water tank, 13—Cold water pump, 14—Heat pump, 15—Stage 1 water-air heat exchanger, 16—Stage 2 water-air heat exchanger, 17—Stage 3 water-air heat exchanger, 18—Stage 4 water-air heat exchanger, 19—Stage 1 air-water heater, 20—Stage 2 air-water heater 21—3-stage gas-water heater; 22—heliostat; 23—absorber; 24—molten salt tank; 25—hot salt pump; 26—reheater; 27—superheater; 28—high-pressure cylinder; 29—low-pressure cylinder; 30—generator; 31—condenser; 32—condensate pump; 33—low-pressure turbine extraction steam; 34—deaerator; 35—feed water pump; 36—high-pressure turbine extraction steam; 37—preheater; 38—evaporator; 39—cold salt pump; 40—cold salt tank; 41—magnesia brick; 42—air circulation channel. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to represent selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Example 1 A novel solar thermal compressed air power generation system, such as Figure 1 As shown, it includes: The concentrating module is used to track the sun via heliostat 1 and reflect and focus sunlight to absorber 2, which converts solar energy into thermal energy and heats compressed air. The thermal storage and structural integration module is used to store compressed air into the heat absorption tower 3 to store the thermal energy of the high-temperature compressed air. Based on the thermal energy of the high-temperature compressed air, the compressed air turbine 4 is driven to rotate. The compressed air turbine 4 is linked to the generator 5 to generate electricity. The generator 5 generates electricity, outputs electrical energy, and discharges low-temperature and low-pressure air. The heat recovery cycle module is used to drive a multi-stage compressor via motor 10 to compress the low-temperature, low-pressure air into low-temperature, high-pressure air. The cold water pump 13 pumps the cold water from the cold water tank 11 to the multi-stage water-air heat exchanger. The heat released during the compression process of the low-temperature, low-pressure air into low-temperature, high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger to generate hot water, which is then stored in the hot water tank 12. The hot water is then pumped from the hot water tank 12 to the heat pump 14 for pressurization to generate low-temperature, high-pressure air. The low-temperature, high-pressure air is preheated by the multi-stage air-water heater and then sent to the heat absorber 2 for reheating, forming a closed-loop thermal energy system.

[0019] The present invention provides some implementation schemes for novel solar thermal compressed air power generation systems that combine the advantages of tower solar thermal power plants and compressed air energy storage power generation, simplify the solar thermal power generation system, reduce initial investment costs, improve power generation efficiency, reduce the cost per kilowatt-hour, generate electricity and store heat at the same time when there is sunlight, and continue to work after sunset by utilizing the stored heat.

[0020] There are several preferred technical solutions that can be implemented based on the above-described technical solutions of the present invention, as detailed below.

[0021] For compressed air turbines, some optimized technical solutions include: A compressed air turbine 4 is a mechanical device used to convert the thermal energy and pressure potential energy of high-temperature, high-pressure compressed air into mechanical energy, thereby driving a generator to produce electricity. The compressed air turbine is similar to an air turbine expander, and in this system specifically refers to the turbine equipment used for compressed air energy conversion.

[0022] In some preferred embodiments of the present invention, when determining the heat absorption tower 3, magnesium oxide bricks 41 are used as the heat storage material for the heat absorption tower 3.

[0023] In this embodiment, magnesium oxide bricks 41 serve as the heat storage material in the heat absorption tower. Some optimized technical solutions include: the primary function of magnesium oxide bricks 41 is heat storage, but their high density also provides a certain load-bearing capacity. The heat absorption tower structure is the existing structure of solar thermal power generation heat absorption towers. The innovation of this invention lies in the internal stacking of magnesium oxide bricks 41, while the external use of a metal tank structure allows it to function as a compressed air storage container. The magnesium oxide bricks 41 are stacked in an orthogonal staggered manner, forming a hollow frustum shape, i.e., stacked vertically layer by layer, to ensure structural stability and functionality. Specifically, as... Figure 4As shown in the partial schematic diagram, the magnesia bricks 41 are arranged in an orthogonal staggered pattern during stacking, with each layer of bricks offset from the previous layer by a certain position (e.g., the edges of the bricks are aligned rather than completely overlapping). This creates gaps between adjacent magnesia bricks 41, forming a uniform gap network that serves as airflow channels 42. These channels allow compressed air to flow evenly throughout the entire interior of the heat absorber tower, optimizing heat exchange efficiency, preventing hotspot formation, and promoting the storage and release of thermal energy. The magnesia bricks 41 themselves have a high density, serving not only as a highly efficient heat storage material but also as a structural support, replacing the complex components of traditional molten salt systems and enabling the heat absorber tower to bear weight and maintain its integrity. Structurally, the heat absorber tower is based on the design of existing solar thermal power generation towers. The exterior uses a metal tank structure to accommodate compressed air storage, while the interior is constructed of magnesia bricks 41 stacked from bottom to top, forming a cylindrical or tower-like outline, similar to a chimney's vertical stacking layout. This achieves integration of heat storage and structure, simplifying the system and reducing costs.

[0024] Some embodiments of this invention explicitly specify that the heat absorption tower uses magnesia brick 41 as the heat storage material. Its design aims to innovate the molten salt system: magnesia brick 41 is inexpensive, high-temperature resistant (withstanding temperatures above 2000℃), and also serves as the structural support for the heat absorption tower, eliminating the need for molten salt-related equipment such as hot molten salt tanks, molten salt pumps, and preheating systems. This significantly reduces costs, simplifies system maintenance, and improves thermal storage stability. Since magnesia brick 41 typically has a density of 3.58 g / cm³ (25℃) and a specific heat capacity of approximately 1.46 kJ / (kg·K) (25℃), it can efficiently store solar thermal energy, solving the problem of intermittent sunlight and ensuring continuous power supply without worrying about the risk of molten salt solidification or corrosion.

[0025] In some embodiments of the present invention, the pressure range of the compressed air in the heat absorber includes, but is not limited to, 3~9 MPa; the temperature range of the heated air can be determined based on technical selection, and in some embodiments, it is controlled at 600~650℃.

[0026] In some embodiments of the present invention, the magnesium oxide bricks 41 are stacked in an orthogonal staggered manner with reserved air circulation channels to optimize heat transfer and air circulation efficiency. The staggered stacking can prevent heat accumulation and ensure that air flows evenly through the gaps between the bricks, which is conducive to maximizing the heat exchange rate, avoiding the formation of hot spots, improving the heating effect of compressed air, and thus improving the overall power generation efficiency. At the same time, the reserved channels simplify the structure of the heat absorption tower, reduce construction complexity, support the dual role of magnesium oxide bricks 41 as structural materials, and further reduce investment.

[0027] Regarding the specific method of generator 5 generating electrical energy and discharging low-temperature, low-pressure air, some optimized technical solutions include: Based on the thermal energy and pressure potential energy of high-temperature compressed air, the compressed air expands and does work in the compressed air turbine 4, driving the blades of the compressed air turbine 4 to rotate, converting the thermal energy and pressure potential energy of the high-temperature compressed air into mechanical energy, and obtaining low-temperature low-pressure air. The compressed air turbine 4 transmits mechanical energy through the main shaft based on the rotation of the blades, and the generator 5's rotor cuts magnetic field lines, converting mechanical energy into electrical energy through electromagnetic induction.

[0028] In some embodiments of the present invention, high-temperature compressed air drives a turbine to expand and perform work, which is converted into mechanical energy and then linked to a generator to generate electricity. By replacing the steam turbine with a compressed air power generation system, the higher theoretical efficiency of air is utilized to achieve direct energy conversion, which can significantly improve power generation efficiency and simplify the process. For example, the turbine blades rotate directly cut magnetic field lines to generate electricity without the need for a steam intermediate link, thus reducing energy loss. At the same time, the discharged low-temperature and low-pressure air can seamlessly enter the heat recovery cycle, ensuring closed-loop operation of the system and enhancing reliability.

[0029] In some preferred embodiments of the compressed air turbine described in this invention, the low-temperature, low-pressure air discharged from the compressed air turbine 4 is connected to a multi-stage compressor.

[0030] In some embodiments of the present invention, the low-temperature, low-pressure air discharged from the compressed air turbine is directly connected to a multi-stage compressor. The purpose is to reuse the waste air after power generation, compress it into high-pressure air, realize a closed loop of thermal energy, reduce external energy demand by recovering waste heat, improve the overall efficiency of the system, simplify the pipeline layout, reduce operating costs, ensure that stored thermal energy can still be used to generate electricity when there is no sunlight, and enhance system stability.

[0031] Regarding the air flow process, some optimized technical solutions include: the low-temperature high-pressure air output by the multi-stage compressor is heated by the heat absorber 2 and transformed into high-temperature high-pressure air, which is stored in the heat absorber tower 3. The high-temperature high-pressure air drives the compressed air turbine 4 to expand and do work, and discharges the low-temperature low-pressure air. The low-temperature low-pressure air is transmitted to the multi-stage compressor, which compresses it into low-temperature high-pressure air and transmits it to the heat absorber, forming a closed loop of air flow.

[0032] For the internal energy conversion process, some optimized technical solutions include: focusing solar energy onto the absorber 2, converting light energy into heat energy to heat low-temperature, high-pressure air, resulting in high-temperature, high-pressure air which is then stored in the absorber tower 3; in the compressed air turbine 4, the high-temperature, high-pressure air expands and does work, driving the blades to rotate, converting the thermal energy and pressure potential energy of the high-temperature, high-pressure air into mechanical energy, resulting in low-temperature, low-pressure air; the mechanical energy is transmitted to the generator 5 through the main shaft, and the rotor cuts magnetic field lines, converting the mechanical energy into electrical energy output through electromagnetic induction; the electrical energy drives a multi-stage compressor to compress the low-temperature, low-pressure air, resulting in low-temperature, high-pressure air, and the heat energy released during the compression process is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is stored in the hot water tank 12; the hot water is drawn from the hot water tank 12, pressurized by the heat pump 14, and flows into the multi-stage air-water heater, where the heat energy of the high-temperature, high-pressure hot water is transferred to the high-temperature, high-pressure air, forming a closed-loop heat energy system.

[0033] Regarding the water flow process, some optimized technical solutions include: using a cold water pump 13 to transport cold water from the cold water tank 11 to a multi-stage water-air heat exchanger to absorb the heat energy released during the compression of low-temperature, low-pressure air by a multi-stage compressor. After absorbing the heat energy, the cold water is heated to generate hot water, which is then stored in the hot water tank 12. The hot water drawn from the hot water tank 12 is pressurized to a high-temperature, high-pressure state by a heat pump 14 and flows into a multi-stage air-water heater to release heat energy and cool down to generate cold water. The water flows back to the cold water tank 11 for recycling, forming a closed-loop water cycle.

[0034] For multi-stage compressors, some optimized technical solutions include: the multi-stage compressor consists of a set number of compressors connected in series. The set number can be determined based on technical selection, including but not limited to determining it through the initial pressure of the compressed air used to generate electricity in the system design. The higher the initial pressure, the more stages are needed. In a selectable embodiment, the set number of multi-stage compressors is four. Figure 3 As shown, it specifically includes a first-stage compressor 6, a second-stage compressor 7, a third-stage compressor 8, and a fourth-stage compressor 9.

[0035] For multi-stage compressors, some optimized technical solutions include: the multi-stage compressor has the same structure for each compressor, but the inlet and outlet pressures of each stage compressor are different.

[0036] Some embodiments of the present invention specify that a multi-stage compressor is composed of multiple compressors connected in series, and each compressor has different inlet and outlet pressures (e.g., 0.1MPa-9MPa), thereby achieving high-efficiency compression, optimizing energy utilization, reducing the overload risk of single-stage compression, and improving system reliability and efficiency. At the same time, multi-stage series connection allows for staged heat recovery, ensuring a smooth transition from low pressure to high pressure and reducing mechanical wear.

[0037] For multi-stage water-air heat exchangers, some optimized technical solutions include: the multi-stage water-air heat exchanger is composed of a set number of water-air heat exchangers connected in parallel. The set number can be determined based on technical selection, including but not limited to determination by matching the number of compression stages. In a selectable embodiment, the set number of water-air heat exchangers is 4. Figure 3 As shown, it specifically includes a primary water-gas heat exchanger 15, a secondary water-gas heat exchanger 16, a tertiary water-gas heat exchanger 17, and a quaternary water-gas heat exchanger 18.

[0038] For multi-stage water-air heat exchangers, some optimized technical solutions include: the multi-stage water-air heat exchanger has, but is not limited to, the structure of each water-air heat exchanger being the same, and each stage of the compressor generating heat during compression. The heat stored in the hot water tank is used to heat the high-pressure compressed air through the air-water heater, thereby improving the efficiency of the compressed air generator. Therefore, a multi-stage water-air heat exchanger is set up to absorb the heat released during the air compression process.

[0039] Some embodiments of the present invention use multiple water-air heat exchangers connected in parallel to form a multi-stage water-air heat exchanger, which absorbs the heat released during air compression, efficiently recovers waste heat, and allows the heat from multiple compression stages to be processed simultaneously through parallel layout. The generated hot water is stored in a tank and then reused to preheat compressed air, thereby improving the system's thermal efficiency, reducing cold water consumption, and simplifying the maintenance process.

[0040] For multi-stage gas-water heaters, some optimized technical solutions include: the multi-stage gas-water heater is composed of a set number of gas-water heaters connected in parallel. The set number can be determined based on technical selection, including but not limited to determination by matching the number of turbine stages. In a selectable embodiment, the set number of gas-water heaters is 3, such as... Figure 3 As shown, it specifically includes a primary gas-water heater 19, a secondary gas-water heater 20, and a tertiary gas-water heater 21.

[0041] For multi-stage gas-water heaters, some optimized technical solutions include: the multi-stage gas-water heater includes, but is not limited to, each gas-water heater having the same structure, such as... Figure 3 As shown, the high-pressure compressed air in each stage is heated by the work done by the three-stage turbine.

[0042] Some embodiments of the present invention, such as existing tower solar thermal power generation technologies Figure 2As shown, solar energy is first tracked and reflected in real time by the heliostat array 22 and focused onto the absorber 23 at the top of the central absorber tower, achieving the initial conversion of light energy into heat energy. The absorber 23 transfers high-temperature heat energy to the molten salt medium. The high-temperature molten salt (approximately 565°C) is stored in the hot molten salt tank 24 and circulated by the hot salt pump 25. At the same time, the low-temperature molten salt is temporarily stored in the cold salt tank 40 and reheated by the cold salt pump 39, which drives the return absorber 23. The molten salt heat energy is used to heat the feedwater system in stages through the evaporator 38 and preheater 37, generating saturated steam that enters the superheater 27 and is heated to high pressure. Steam is reheated a second time in reheater 26 to improve efficiency. After the high-temperature, high-pressure steam drives the high-pressure cylinder 28 to expand and do work, part of the steam is diverted to the feedwater preheating system through the high-pressure steam generator extraction 36, while the remaining steam enters the low-pressure cylinder 29 to continue expanding, driving the generator 30 to convert mechanical energy into electrical energy output. The discharged low-pressure exhaust steam enters the condenser 31 for liquefaction, is then transported by the condensate pump 32 to the low-pressure steam generator extraction 33 for preheating, and is then deoxygenated by the deaerator 34 before being pressurized by the feedwater pump 35, completing a closed-loop cycle from condensate to boiler feedwater, realizing the recovery and reuse of water resources. This process relies on a complex molten salt-steam dual energy conversion chain, resulting in limited system efficiency and high equipment maintenance costs. This process generates a large amount of heat energy loss, highlighting the inherent defects of the system in terms of efficiency, cost, and water consumption.

[0043] In some embodiments of this invention, existing compressed air energy storage power generation technology, as a physical energy storage solution, is divided into two main stages: energy storage and energy release for power generation. In the energy storage stage (off-peak hours), an electric motor drives a multi-stage compressor to compress ambient air into high-pressure air. The heat released during compression is stored in a heat storage medium (such as molten salt in existing tower-type solar thermal power generation technology) through a heat exchanger. The high-pressure air is stored in underground salt caverns or artificial gas storage tanks. In the energy release for power generation stage (peak hours), the stored high-pressure air is released through a release valve. It is first preheated by absorbing the stored heat energy through a heat exchanger, and then enters the combustion chamber to mix and burn with natural gas or directly utilize the stored heat to generate high-temperature, high-pressure gas that drives an expansion turbine unit (including high-pressure and low-pressure turbines) to rotate, which in turn drives a generator to output electrical energy, ultimately discharging low-temperature exhaust gas. Compressed air energy storage power generation technology utilizes surplus electricity to compress and store energy during off-peak hours, and releases the compressed air during peak hours to drive the turbine for power generation, achieving energy transfer over time and peak shaving for the power grid.

[0044] Some embodiments of the present invention use multiple air-water heaters connected in parallel to form a multi-stage air-water heater for preheating low-temperature high-pressure compressed air, which helps to optimize thermal energy utilization. By heating the inlet air of multiple turbines simultaneously in parallel, the energy demand of the heat absorber is reduced, ensuring efficient turbine operation.

[0045] Example 2 A novel method for generating electricity using solar thermal compressed air, comprising: The heliostat 1 tracks the sun and reflects and focuses sunlight onto the absorber 2, which converts solar energy into heat energy and heats low-temperature, high-pressure air to obtain high-temperature, high-pressure air. High-temperature and high-pressure air is stored in heat absorption tower 3. The heat energy of the high-temperature and high-pressure air drives the compressed air turbine 4 to rotate. The compressed air turbine 4 is linked to the generator 5 to generate electricity. The generator 5 generates electricity and outputs electrical energy and discharges low-temperature and low-pressure air from the compressed air turbine 4. The low-temperature, low-pressure air is compressed into low-temperature, high-pressure air by a multi-stage compressor driven by motor 10, and then delivered to the heat absorber 2. The cold water pump 13 delivers the cold water drawn from the cold water tank 11 to the multi-stage water-air heat exchanger. The heat released during the compression process of the low-temperature, low-pressure air into low-temperature, high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is stored in the hot water tank 12. The hot water is drawn from the hot water tank 12 and pressurized by the heat pump 14 to generate high-temperature, high-pressure hot water. The high-temperature, high-pressure hot water flows into the multi-stage air-water heater, and the heat energy of the high-temperature, high-pressure hot water is incorporated into the high-temperature, high-pressure air that has passed through the multi-stage air-water heater, forming a closed loop of air flow.

[0046] There are several preferred technical solutions that can be implemented based on the above-described technical solutions of the present invention, as detailed below.

[0047] For heat absorption towers using magnesia bricks 41 as the heat storage material, some optimized technical solutions include: Heat absorption tower 3 uses magnesia bricks 41 as the heat storage material, and the magnesia bricks 41 are stacked in an orthogonal staggered manner, providing structural support for the heat absorption tower and reserving air circulation channels. Specific results are as follows: Figure 4 As shown.

Claims

1. A novel solar thermal compressed air power generation system, characterized in that, It includes: The concentrating module is used to track the sun through a heliostat (1) and reflect and focus sunlight to a heat absorber (2), which converts solar energy into thermal energy and heats low-temperature high-pressure air to obtain high-temperature high-pressure air; The thermal storage and structural integration module is used to store high-temperature and high-pressure air into the heat absorption tower (3). Based on the thermal energy of the high-temperature and high-pressure air, the compressed air turbine (4) is driven to rotate. The compressed air turbine (4) is linked to the generator (5) to generate electricity. The generator (5) generates electricity and discharges low-temperature and low-pressure air from the compressed air turbine (4). The heat recovery cycle module is used to drive the multi-stage compressor via motor (10) to compress the low-temperature low-pressure air into low-temperature high-pressure air, and the low-temperature high-pressure air is delivered to the heat absorber (2); the cold water pump (13) delivers the cold water drawn from the cold water tank (11) to the multi-stage water-air heat exchanger. The heat released during the compression process of compressing the low-temperature low-pressure air into low-temperature high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water and storing it in the hot water tank (12). The hot water is drawn from the hot water tank (12) to the heat pump (14) for pressurization, generating high-temperature high-pressure hot water. The high-temperature high-pressure hot water flows into the multi-stage air-water heater, and the heat energy of the high-temperature high-pressure hot water is incorporated into the high-temperature high-pressure air that has passed through the multi-stage air-water heater, forming a closed loop of air flow.

2. The novel solar thermal compressed air power generation system according to claim 1, characterized in that, It includes: The heat absorption tower (3) uses magnesium oxide bricks (41) as the heat storage material.

3. A novel solar thermal compressed air power generation system according to claim 2, characterized in that, It includes: The magnesium oxide bricks (41) are stacked into a multi-layered orthogonal staggered structure, and air circulation channels (42) are provided between adjacent magnesium oxide bricks (41).

4. A novel solar thermal compressed air power generation system according to claim 1, characterized in that, It includes: The specific method by which the generator (5) generates electricity and discharges low-temperature, low-pressure air from the compressed air turbine (4) is as follows: Based on the thermal energy and pressure potential energy of high temperature and high pressure air, the high temperature and high pressure air expands and does work in the compressed air turbine (4), which drives the blades of the compressed air turbine (4) to rotate, converting the thermal energy and pressure potential energy of the high temperature and high pressure air into mechanical energy, and obtaining low temperature and low pressure air. The compressed air turbine (4) transmits mechanical energy through the main shaft based on the rotation of the blades, and the generator (5) uses the rotor to cut magnetic field lines and convert mechanical energy into electrical energy through electromagnetic induction.

5. A novel solar thermal compressed air power generation system according to claim 1, characterized in that, It includes: the low-temperature, low-pressure air discharged from the compressed air turbine (4) is transmitted to a multi-stage compressor.

6. A novel solar thermal compressed air power generation system according to claim 1 or 5, characterized in that, It includes: The low-temperature high-pressure air output by the multi-stage compressor is heated by the heat absorber (2) and transformed into high-temperature high-pressure air, which is stored in the heat absorber tower (3). The high-temperature high-pressure air drives the compressed air turbine (4) to expand and do work, and discharges the low-temperature low-pressure air. The low-temperature low-pressure air is transmitted to the multi-stage compressor, compressed into low-temperature high-pressure air by the multi-stage compressor and transmitted to the heat absorber, forming a closed loop of air flow.

7. A novel solar thermal compressed air power generation system according to claim 1, characterized in that, It includes: Based on the solar energy focused onto the absorber (2), the light energy is converted into heat energy to heat the low-temperature high-pressure air, resulting in high-temperature high-pressure air which is stored in the heat absorption tower (3). In the compressed air turbine (4), the high-temperature high-pressure air expands and does work, driving the blades to rotate, converting the heat energy and pressure potential energy of the high-temperature high-pressure air into mechanical energy, resulting in low-temperature low-pressure air. The mechanical energy is transmitted to the generator (5) through the main shaft, and the rotor cuts the magnetic field lines, converting the mechanical energy into electrical energy output through electromagnetic induction. The electrical energy drives the multi-stage compressor to compress the low-temperature low-pressure air, resulting in low-temperature high-pressure air. The heat energy released during the compression of the low-temperature low-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is stored in the hot water tank (12). The hot water is drawn from the hot water tank (12), pressurized by the heat pump (14), and flows into the multi-stage air-water heater. The heat energy of the high-temperature high-pressure hot water is transferred to the high-temperature high-pressure air, forming a closed loop of heat energy.

8. A novel solar thermal compressed air power generation system according to claim 1, characterized in that, It includes: The cold water in the cold water tank (11) is transported to the multi-stage water-air heat exchanger by the cold water pump (13), which absorbs the heat energy released during the compression of low-temperature and low-pressure air by the multi-stage compressor. After absorbing the heat energy, the cold water is heated to generate hot water, which is stored in the hot water tank (12). The hot water drawn from the hot water tank (12) is pressurized to a high temperature and high pressure state by the heat pump (14) and flows into the multi-stage air-water heater, where it releases heat energy to cool down and generate cold water. The water flows back to the cold water tank (11) for recycling, forming a closed-loop water cycle.

9. A novel method for generating electricity using solar thermal compressed air, characterized in that, It includes: The sun is tracked by a heliostat (1) and the sunlight is reflected and focused to a heat absorber (2). The heat absorber (2) converts solar energy into thermal energy and heats low-temperature high-pressure air to obtain high-temperature high-pressure air. High-temperature and high-pressure air is stored in the heat absorption tower (3). Based on the heat energy of the high-temperature and high-pressure air, the compressed air turbine (4) is driven to rotate. The compressed air turbine (4) is linked to the generator (5) to generate electricity. The generator (5) generates electricity and outputs electrical energy and discharges low-temperature and low-pressure air from the compressed air turbine (4). The low-temperature, low-pressure air is compressed into low-temperature, high-pressure air by a multi-stage compressor driven by a motor (10). The low-temperature, high-pressure air is then transported to the heat absorber (2). The cold water pump (13) pumps the cold water drawn from the cold water tank (11) to the multi-stage water-air heat exchanger. The heat released during the compression process of the low-temperature, low-pressure air into low-temperature, high-pressure air is absorbed by the cold water in the multi-stage water-air heat exchanger, generating hot water which is then stored in the hot water tank (12). The hot water is drawn from the hot water tank (12) and pressurized by the heat pump (14) to generate high-temperature, high-pressure hot water. The high-temperature, high-pressure hot water flows into the multi-stage air-water heater, and the heat energy of the high-temperature, high-pressure hot water is incorporated into the high-temperature, high-pressure air that has passed through the multi-stage air-water heater, forming a closed loop of air flow.

10. A novel method for generating electricity using solar thermal compressed air according to claim 9, characterized in that, It includes: The heat absorption tower (3) uses magnesium oxide bricks (41) as heat storage material. The magnesium oxide bricks (41) are stacked into a multi-layer orthogonal staggered structure, and air circulation channels (42) are set between adjacent magnesium oxide bricks (41).

Images