Photo-thermal power generation system and power generation method

Abstract

The invention provides a photo-thermal power generation system and method, and relates to the technical field of power generation systems, and the system comprises three hot molten salt pipelines, a preheater, an evaporator, a superheater, a high-pressure reheater, a low-pressure reheater and two turbines. The hot molten salt pipelines feed molten salt into the superheater, the high-pressure reheater and the low-pressure reheater correspondingly. Feed water sequentially enters the preheater, the evaporator and the superheater to be heated to preset temperature steam. And the steam firstly expands to do work in the first turbine, then enters the high-pressure reheater to exchange heat with the fused salt to obtain reheated steam, and expands to do work again in the second turbine. And finally, the steam enters a low-pressure reheater to exchange heat with the fused salt to obtain low-pressure reheated steam, and the low-pressure reheated steam enters a steam condensing system of the power generation system after acting in a second turbine, so that complete circulation of power generation is realized. According to the system, on the basis that an original photo-thermal power generation thermodynamic system is reserved, fused salt and water / water vapor heat exchange is reconstructed, so that super (super) critical and subcritical parameters can be generated, and the power generation efficiency of the system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of power generation systems, and in particular to a solar thermal power generation system and a power generation method. Background Art

[0002] With the proposal of my country's "3060" dual carbon target, my country's new energy installed capacity has developed rapidly. Relevant calculations show that my country's new energy installed capacity will exceed coal-fired power to become the country's largest power source by 2035, and the proportion of coal-fired power and new energy power generation will reverse in 2050. It is estimated that by 2035, the scale of wind and solar installed capacity will reach 700 million and 650 million kilowatts respectively, and the maximum daily power fluctuations of wind power and solar energy in the country are expected to reach 200 million and 400 million kilowatts respectively. Among the many types of clean energy, solar thermal power generation has the conditions to gradually serve as a new energy source for basic power load. As the only long-term clean energy form that is currently expected to replace thermal power as basic power, it converts solar energy into thermal energy and uses thermal energy to generate superheated steam to drive the unit to generate electricity. And compared with other forms of new energy power generation, the circulating medium in the solar thermal power generation system is mainly molten salt in addition to water. The characteristics of molten salt itself determine that the solar thermal power generation system has the function of energy storage and can play a role in peak regulation. Therefore, solar thermal power generation has more advantages than other forms of renewable energy power generation, but the steam pressure generally used in the currently operating solar thermal power generation systems is ultra-high pressure (about 14MPa), resulting in low efficiency of the entire solar thermal power generation system.

[0003] In order to improve the efficiency of the CSP system, the supercritical parameter medium used in the prior art is CO2. However, the equipment used to use supercritical CO2 as the power generation cycle medium is very different from the equipment used in the current CSP power plants, and it is impossible to carry out partial transformation and upgrading of the currently operating CSP power plants. In addition, the current structure of the steam turbine is not suitable for power generation using supercritical pressure steam. Summary of the invention

[0004] In view of the above problems, the present application provides a solar thermal power generation system and a power generation method, including the following contents:

[0005] In a first aspect, the present application provides a solar thermal power generation system, characterized in that the system comprises: a water supply pipeline, a first hot molten salt pipeline, a second hot molten salt pipeline, a third hot molten salt pipeline, a preheater, an evaporator, a superheater, a high-pressure reheater, a low-pressure reheater, a first turbine, and a second turbine;

[0006] The first hot molten salt pipeline is used to pass the molten salt into the superheater; the second hot molten salt pipeline is used to pass the molten salt into the high-pressure reheater; the third hot molten salt pipeline is used to pass the molten salt into the low-pressure reheater;

[0007] The water supply pipeline is used to sequentially input the water supply into the preheater, the evaporator and the superheater for heating to obtain steam meeting a preset temperature;

[0008] The first turbine is used to provide an expansion and work-making environment for the steam meeting the preset temperature;

[0009] The high-pressure reheater is used to exchange heat between the steam input into the high-pressure reheater from the first turbine and the molten salt entering from the second hot molten salt pipeline to obtain reheated steam;

[0010] The second turbine is used to provide an expansion and work-performing environment for the reheated steam;

[0011] The low-pressure reheater is used to exchange heat between the steam input into the low-pressure reheater from the second turbine and the molten salt entering from the third hot molten salt pipeline to obtain low-pressure reheated steam;

[0012] The second turbine is further used to provide an expansion and work-performing environment for the low-pressure reheat steam.

[0013] Optionally, the first turbine is a centripetal turbine, and the second turbine is an axial turbine.

[0014] Optionally, the molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:4.

[0015] Optionally, the axial flow turbine includes a high-pressure cylinder and medium- and low-pressure cylinders; after the reheated steam enters the high-pressure cylinder to expand, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders to expand and do work.

[0016] Optionally, the temperature of the steam meeting the preset temperature is 550° C., and the steam pressure is subcritical, supercritical, or ultra-supercritical.

[0017] In a second aspect, the present application provides a method for generating electricity through a solar thermal power generation system, the method comprising:

[0018] The molten salt is passed into the superheater through the first hot molten salt pipeline; the molten salt is passed into the high-pressure reheater through the second hot molten salt pipeline; the molten salt is passed into the low-pressure reheater through the third hot molten salt pipeline;

[0019] Feed water is sequentially fed into the preheater, the evaporator and the superheater through a feed water pipeline for heating to obtain steam meeting a preset temperature; the steam meeting the preset temperature is fed into the first turbine for expansion and work;

[0020] The steam that has completed expansion and work in the first turbine is input into a high-pressure reheater to exchange heat with the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; the reheated steam is passed into the second turbine to expand and do work;

[0021] The steam input into the low-pressure reheater from the second turbine is heat-exchanged with the molten salt entering from the third hot molten salt pipeline in the low-pressure reheater to obtain low-pressure reheated steam; the low-pressure reheated steam is expanded and does work in the second turbine, and the expanded steam enters the condensing system of the power generation system, completing the complete cycle of power generation.

[0022] Optionally, the first turbine is a centripetal turbine, and the second turbine is an axial turbine.

[0023] Optionally, the molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:4.

[0024] Optionally, the axial flow turbine includes a high-pressure cylinder and medium- and low-pressure cylinders, and the method includes: after the reheated steam enters the high-pressure cylinder to expand, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders to expand and do work.

[0025] Optionally, the temperature of the steam meeting the preset temperature is 550° C., and the steam pressure is subcritical, supercritical, or ultra-supercritical.

[0026] The present application provides a solar thermal power generation system, in which, after the structure of the solar thermal power generation system is modified, high-temperature steam with ultra-supercritical pressure can be generated, and finally the ultra-high pressure steam turbine generator set of the solar thermal system can be transformed into a supercritical generator set. The solar thermal power generation system in the present application includes: a water supply pipeline, a first hot molten salt pipeline, a second hot molten salt pipeline, a third hot molten salt pipeline, a preheater, an evaporator, a superheater, a high-pressure reheater, a low-pressure reheater, a first turbine and a second turbine; the first hot molten salt pipeline is used to pass the molten salt into the superheater; the second hot molten salt pipeline is used to pass the molten salt into the high-pressure reheater; the third hot molten salt pipeline is used to pass the molten salt into the low-pressure reheater; the water supply pipeline is used to feed the water into the preheater, the evaporator and the superheater in sequence for heating to obtain steam that meets the preset temperature; The first turbine is used to provide an expansion working environment for the steam that meets the preset temperature; the high-pressure reheater is used to exchange heat between the steam input from the first turbine to the high-pressure reheater and the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; the second turbine is used to provide an expansion working environment for the reheated steam; the low-pressure reheater is used to exchange heat between the steam input from the second turbine to the low-pressure reheater and the molten salt entering from the third hot molten salt pipeline to obtain low-pressure reheated steam; the second turbine is also used to provide an expansion working environment for the low-pressure reheated steam. Through the distribution of heat energy between the superheater, high-pressure reheater, and low-pressure reheater set in the system, the solar thermal power generation system in the present application can generate supercritical and subcritical parameters when using water vapor as a supercritical power generation working medium, so as to improve the efficiency of the solar thermal power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in this embodiment 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 only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A schematic diagram of the structure of a solar thermal power generation system provided in an embodiment of the present application;

[0029] Figure 2 A flow chart of a method for generating electricity in a solar thermal power generation system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] As described in the background technology of this application, the steam pressure commonly used in the CSP system is ultra-high pressure (about 14MPa), which leads to low efficiency of the entire CSP system. In order to improve the efficiency of the CSP system, the prior art uses supercritical CO2 as a power generation circulation medium instead of water vapor to improve the efficiency of the power generation system. Since the equipment used for using supercritical CO2 as a power generation circulation medium is very different from the equipment used in the CSP power station, supercritical CO2 cannot be directly used as a power generation circulation medium for the CSP power generation equipment. Therefore, the prior art still has the problem of low efficiency of the entire CSP system when using water vapor as a power generation medium.

[0031] In order to solve the above technical problems, an embodiment of the present application provides a solar thermal power generation system, characterized in that the system includes: a water supply pipeline, a first molten salt pipeline, a second molten salt pipeline, a third molten salt pipeline, a preheater, an evaporator, a superheater, a high-pressure reheater, a low-pressure reheater, a first turbine and a second turbine; the first molten salt pipeline is used to pass the molten salt into the superheater; the second molten salt pipeline is used to pass the molten salt into the high-pressure reheater; the third molten salt pipeline is used to pass the molten salt into the low-pressure reheater; the water supply pipeline is used to feed water into the preheater, the evaporator and the superheater in sequence for heating , to obtain steam that meets the preset temperature; the first turbine is used to provide an expansion working environment for the steam that meets the preset temperature; the high-pressure reheater is used to exchange heat between the steam input from the first turbine to the high-pressure reheater and the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; the second turbine is used to provide an expansion working environment for the reheated steam; the low-pressure reheater is used to exchange heat between the steam input from the second turbine to the low-pressure reheater and the molten salt entering from the third hot molten salt pipeline to obtain low-pressure reheated steam; the second turbine is also used to provide an expansion working environment for the low-pressure reheated steam. On the basis of retaining the original solar thermal power generation thermal system, the system reconstructs the heat exchange between molten salt and water / steam, so that supercritical and subcritical parameters can be generated to improve the power generation efficiency of the system.

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0033] Figure 1 A schematic diagram of a solar thermal power generation system provided in an embodiment of the present application, combined with Figure 1As shown, the solar thermal power generation system provided in the embodiment of the present application may include:

[0034] Pipelines 1-1, 1-2, 1-3, 1-4, 1-5, 1-6, 1-7, 1-8, 1-9, 3-2, 3-3, 3-4, 3-5, 3-6, 4-2, 5-2; preheater 2-1, evaporator 2-2 and superheater 2-3; first molten salt pipeline 3-1, second molten salt pipeline 4-1, third molten salt pipeline 5-1; first turbine 6-1; high-pressure cylinder 6-2 of the second turbine; medium and low-pressure cylinders 6-3 of the second turbine; high-pressure reheater 7-1 and low-pressure reheater 7-2.

[0035] The first hot molten salt pipeline 3-1 is used to pass the molten salt into the superheater 2-3; the second hot molten salt pipeline 4-1 is used to pass the molten salt into the high-pressure reheater 7-1; the third hot molten salt pipeline 5-1 is used to pass the molten salt into the low-pressure reheater 7-2; the pipeline 1-1 is used as a water supply pipeline to sequentially input the feed water into the preheater 2-1, the evaporator 2-2 and the superheater 2-3 for heating to obtain steam that meets the preset temperature; the first turbine 6-1 is used to provide an expansion work cycle for the steam that meets the preset temperature environment; the high-pressure reheater 7-1 is used to exchange heat between the steam input from the first turbine 6-1 to the high-pressure reheater 7-1 and the molten salt entering from the second hot molten salt pipeline 4-1 to obtain reheated steam; the second turbine is used to provide an expansion and working environment for the reheated steam; the low-pressure reheater is used to exchange heat between the steam input from the second turbine to the low-pressure reheater and the molten salt entering from the third hot molten salt pipeline to obtain low-pressure reheated steam; the second turbine is also used to provide an expansion and working environment for the low-pressure reheated steam.

[0036] The first turbine is a centripetal turbine, and the second turbine is an axial turbine. The centripetal turbine can avoid the partial steam inlet structure of the high-parameter small-capacity axial turbine, thereby improving operating efficiency and safety.

[0037] The molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:4. It has fluidity, economy and stability. It is a commonly used high-temperature heat transfer and heat storage fluid with an operating temperature of 565°C and has been widely used in solar thermal power generation systems around the world.

[0038] The axial flow turbine includes a high-pressure cylinder and a medium- and low-pressure cylinder; after the reheated steam enters the high-pressure cylinder for expansion, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders for expansion and work. The temperature of the steam that meets the preset temperature is 550°C, and the steam pressure is subcritical, supercritical, or ultra-supercritical.

[0039] The following is an introduction to the overall working process of the CSP system:

[0040] The molten salt in the hot molten salt storage tank in the solar thermal power generation system is pumped into the first hot molten salt pipeline 3-1, the second hot molten salt pipeline 4-1, and the third hot molten salt pipeline 5-1 through the hot molten salt pump. The hot molten salt in the three pipelines enters the superheater 2-3, the high-pressure reheater 7-1 and the low-pressure reheater 7-2 respectively. The feed water in the power generation system enters the preheater 2-1, the evaporator 2-2 and the superheater 2-3 in turn through the pipeline 1-1, and finally enters the turbine 6-1 after being heated by the hot molten salt to become qualified steam. The turbine 6-1 adopts a centripetal structure to avoid the reduced efficiency and increased difficulty of equipment processing caused by the partial steam inlet structure of the high-parameter steam axial flow turbine. After the steam in the turbine 6-1 expands, it enters the high-pressure reheater 7-1 through the pipeline 1-5 and exchanges heat with the high-temperature molten salt entering the heat exchanger 7-1 through the molten salt pipeline 4-1. The steam pressure in pipeline 1-4 is subcritical, supercritical or ultra-supercritical, and the temperature is 550℃. After expansion through turbine 6-1, the parameters are ultra-high pressure 14MPa, about 450℃, and then heated through high-pressure reheater 7-1 to 550℃, and the pressure is about 14MPa before entering reheat steam pipeline 1-6. The reheated steam with ultra-high pressure parameters (14MPa, about 550℃) enters the high-pressure cylinder 6-2 of the axial flow turbine through pipeline 1-6, and after expansion in the high-pressure cylinder, enters the low-pressure reheater 7-2 to exchange heat with the molten salt from the hot molten salt storage tank to produce qualified low-pressure reheated steam, which enters the medium and low pressure cylinders 6-3 of the axial flow turbine to expand and do work. The expanded steam enters the condensing system of the power generation system through pipeline 1-9, and finally realizes the complete cycle of power generation.

[0041] The solar thermal power generation system provided in this application uses water vapor as a supercritical power generation medium, and retains the main thermal system of a conventional solar thermal power station, but redistributes heat energy of different grades to produce high-parameter steam. In the system, turbine 6-1 adopts a centripetal turbine with mature structure and high operating efficiency, rather than an integrated axial flow turbine, but combines a supercritical centripetal turbine and an ultra-high pressure axial flow turbine for power generation. This design not only avoids the partial steam inlet structure of a high-parameter small-capacity axial flow turbine, improves operating efficiency and safety, but also reconstructs the heat exchange system for heating steam with molten salt, which can produce supercritical and subcritical parameters, and these steam parameters do not exceed 565°C, which is different from conventional thermal power generation units. At the same time, the reconstruction of the heat exchange system also improves the power generation efficiency. On the basis of keeping the ultra-high pressure steam power generation power of a conventional solar thermal power station unchanged, a high-parameter centripetal turbine arrangement is added. Although the overall heat storage capacity needs to be increased, the increase is less than the increase in power generation efficiency. Therefore, compared with conventional solar thermal power generation systems with the same power generation capacity, the overall heat storage capacity of this system is reduced, the project investment is reduced, and the investment in the mirror field can also be reduced.

[0042] Figure 2 A flow chart of a method for generating electricity using a solar thermal power generation system provided in an embodiment of the present application. Figure 2 As shown, the power generation method of the solar thermal power generation system provided in the embodiment of the present application may include:

[0043] S201, passing molten salt into a superheater through a first hot molten salt pipeline; passing molten salt into a high-pressure reheater through a second hot molten salt pipeline; passing molten salt into a low-pressure reheater through a third hot molten salt pipeline;

[0044] S202, feeding water into the preheater, the evaporator and the superheater in sequence through the water feed pipe for heating to obtain steam meeting a preset temperature; passing the steam meeting the preset temperature into the first turbine for expansion and work;

[0045] S203, inputting the steam that has completed expansion and work in the first turbine into a high-pressure reheater, exchanging heat with the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; the reheated steam is passed into the second turbine to expand and do work;

[0046] S204. The steam input into the low-pressure reheater from the second turbine is heat-exchanged with the molten salt input from the third hot molten salt pipeline in the low-pressure reheater to obtain low-pressure reheated steam; the low-pressure reheated steam is expanded and does work in the second turbine, and the expanded steam enters the condensing system of the power generation system, completing a complete cycle of power generation.

[0047] In an implementation method of an embodiment of the present application, the first turbine is a centripetal turbine, and the second turbine is an axial turbine.

[0048] In one implementation method of an embodiment of the present application, the molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:4.

[0049] In an implementation method of an embodiment of the present application, the axial flow turbine includes a high-pressure cylinder and medium- and low-pressure cylinders, and the method includes: after the reheated steam enters the high-pressure cylinder for expansion, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders for expansion and work.

[0050] In an implementation method of an embodiment of the present application, the temperature of the steam that meets the preset temperature is 550° C., and the steam pressure is subcritical, supercritical, or ultra-supercritical.

[0051] The implementation process of the power generation method of the above-mentioned solar thermal power generation system can refer to the introduction of the solar thermal power generation system, which will not be repeated here.

[0052] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0053] It should also be noted that the various embodiments in this specification are described in a progressive manner, and the same and similar parts between the various embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiments. The device and system embodiments described above are merely schematic, in which the units described as separate components may or may not be physically separated, and the components indicated as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0054] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A solar thermal power generation system, characterized in that: The system comprises: a feed water pipeline, a first hot molten salt pipeline, a second hot molten salt pipeline, a third hot molten salt pipeline, a preheater, an evaporator, a superheater, a high-pressure reheater, a low-pressure reheater, a first turbine and a second turbine; The first hot molten salt pipeline is used to pass the molten salt into the superheater; the second hot molten salt pipeline is used to pass the molten salt into the high-pressure reheater; the third hot molten salt pipeline is used to pass the molten salt into the low-pressure reheater; The water supply pipeline is used to sequentially input the water supply into the preheater, the evaporator and the superheater for heating to obtain steam meeting a preset temperature; The first turbine is used to provide an expansion and work-making environment for the steam meeting the preset temperature; The high-pressure reheater is used to exchange heat between the steam input into the high-pressure reheater from the first turbine and the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; The second turbine is used to provide an expansion and work-performing environment for the reheated steam; The low-pressure reheater is used to exchange heat between the steam input into the low-pressure reheater from the second turbine and the molten salt entering from the third hot molten salt pipeline to obtain low-pressure reheated steam; The second turbine is further used to provide an expansion and work-performing environment for the low-pressure reheat steam.

2. The solar thermal power generation system according to claim 1, characterized in that: The first turbine is a centripetal turbine, and the second turbine is an axial turbine.

3. The solar thermal power generation system according to claim 1, characterized in that: The molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:

4.

4. The solar thermal power generation system according to claim 2, characterized in that: The axial flow turbine includes a high-pressure cylinder and medium- and low-pressure cylinders; after the reheated steam enters the high-pressure cylinder and expands, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders for expansion and work.

5. The solar thermal power generation system according to claim 1, characterized in that: The temperature of the steam meeting the preset temperature is 550° C., and the steam pressure is subcritical, supercritical, or ultra-supercritical.

6. A method for generating electricity using a solar thermal power generation system, characterized in that: Based on the solar thermal power generation system described in any one of claims 1 to 5 above, the method comprises: The molten salt is passed into the superheater through the first hot molten salt pipeline; the molten salt is passed into the high-pressure reheater through the second hot molten salt pipeline; the molten salt is passed into the low-pressure reheater through the third hot molten salt pipeline; Feed water is sequentially fed into the preheater, the evaporator and the superheater through a feed water pipeline for heating to obtain steam meeting a preset temperature; the steam meeting the preset temperature is fed into the first turbine for expansion and work; The steam that has completed expansion and work in the first turbine is input into a high-pressure reheater to exchange heat with the molten salt entering from the second hot molten salt pipeline to obtain reheated steam; the reheated steam is passed into the second turbine to expand and do work; The steam input into the low-pressure reheater from the second turbine is heat-exchanged with the molten salt entering from the third hot molten salt pipeline in the low-pressure reheater to obtain low-pressure reheated steam; the low-pressure reheated steam is expanded and does work in the second turbine, and the expanded steam enters the condensing system of the power generation system, completing the complete cycle of power generation.

7. The method for generating electricity using a solar thermal power generation system according to claim 6, characterized in that: The first turbine is a centripetal turbine, and the second turbine is an axial turbine.

8. The method for generating electricity using a solar thermal power generation system according to claim 6, characterized in that: The molten salt is a binary salt Solar Salt, which is composed of NaNO3 and KNO3 in a mass ratio of 6:

4.

9. The method for generating electricity using a solar thermal power generation system according to claim 7, characterized in that: The axial flow turbine comprises a high-pressure cylinder and medium- and low-pressure cylinders, and the method comprises: after the reheated steam enters the high-pressure cylinder for expansion, it enters the low-pressure reheater for heat exchange, and after generating low-pressure reheated steam, it enters the medium- and low-pressure cylinders for expansion and work.

10. The method for generating electricity through a solar thermal power generation system according to claim 6, characterized in that: The temperature of the steam meeting the preset temperature is 550° C., and the steam pressure is subcritical, supercritical, or ultra-supercritical.

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