Carnot cell system driven by ocean temperature difference energy

Abstract

The invention relates to the technical field of energy storage and conversion, and discloses a Carnot cell system driven by ocean temperature difference energy, comprising: an energy charging circulation system, which drives a first organic working medium to circularly flow through excess electric power and exchanges heat with deep seawater to form a cold working medium; the energy storage device exchanges heat with a cold-state working medium generated by the energy charging circulating system to form a cold medium and stores the cold medium; and a second organic working medium flows in the energy release circulating system in a Rankine cycle mode, the second organic working medium can exchange heat with surface seawater to form superheated steam, a generator is driven to generate electricity, a low-temperature and low-pressure working medium is formed, and the low-temperature and low-pressure working medium exchanges heat with the cooling capacity medium in the energy storage device and is condensed to form the liquid second organic working medium. In the electricity consumption trough period, the excess power of the power grid is stored in the form of a cold medium by utilizing the low temperature of deep seawater; in the peak period of electricity utilization, the high temperature of surface seawater is utilized, power is generated in a Rankine cycle mode, and the cooling capacity medium stored in the valley period of electricity utilization is utilized to condense a Rankine cycle working medium.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage and conversion, and in particular to a Carnot battery system driven by ocean temperature difference energy. Background Art

[0002] Energy storage technology is a key enabler for achieving efficient utilization and a stable supply of renewable energy. It can store electricity generated by renewable energy in the form of kinetic energy, thermal energy, and other forms, releasing it when needed, effectively resolving the mismatch between electricity supply and demand.

[0003] The Carnot Battery is an emerging energy storage technology. When renewable energy generates excess electricity, it converts the excess energy into the internal energy of the working fluid through a compressor and other structures, which is stored in a high-temperature heat source and a low-temperature heat source respectively. During peak electricity consumption periods, it generates electricity through a forward heat engine cycle to disperse the burden on the power grid during peak electricity consumption periods.

[0004] Ocean thermal energy is a highly promising marine renewable energy source. Its energy source is based on the temperature difference between the ocean's surface and deep waters. Surface waters are typically warmer due to factors like solar radiation, while the deep sea (below 800 meters) is cooler, typically maintaining a temperature between 4 and 6 degrees Celsius. Combining the Carnot battery with ocean thermal energy could not only enable the storage and release of excess electricity, but also expand the battery's application scenarios, fully leveraging the advantages of low-grade renewable energy.

[0005] In view of this, how to provide an energy storage system that combines Carnot batteries with ocean temperature difference energy is an urgent problem that needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of the present invention is to provide a Carnot battery system driven by ocean temperature difference energy to solve the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides a Carnot battery system driven by ocean temperature difference energy, comprising:

[0008] an energy-charging circulation system disposed near the deep seawater, wherein a first organic working medium circulates within the system, the energy-charging circulation system being electrically connected to the power grid, and utilizing excess electricity to drive the first organic working medium to circulate and exchange heat with the deep seawater to form a cold working medium;

[0009] An energy storage device, which exchanges heat with the cold working fluid generated by the charging circulation system to form a cold medium and stores it;

[0010] The energy release circulation system is arranged close to the surface seawater, and a second organic working fluid flows inside it in a Rankine cycle. The second organic working fluid can exchange heat with the surface seawater to form superheated steam. The superheated steam drives the generator to generate electricity and form a low-temperature, low-pressure working fluid. The low-temperature, low-pressure working fluid exchanges heat with the cold medium in the energy storage device and condenses to form a liquid second organic working fluid.

[0011] Furthermore, the charging cycle system includes: a compressor, a charging cycle condenser, a throttle valve and a charging cycle evaporator connected in sequence, the outlet of the charging cycle evaporator is connected to the compressor; the compressor is electrically connected to the power grid, the charging cycle evaporator exchanges heat with the heat storage medium in the energy storage device through a first heat storage medium loop, the heat storage medium is heat exchanged to form a cold medium and stored, the cold working fluid is heat exchanged with the heat storage medium to form a first organic working fluid and reflux to the charging cycle evaporator.

[0012] Furthermore, the deep seawater is provided with a deep seawater pump, and the deep seawater pump is used to pump the deep seawater to the charging cycle condenser.

[0013] Furthermore, the energy release cycle system includes: an energy release cycle condenser, a working fluid pump, an energy release cycle evaporator and a turbine connected in sequence, and the outlet of the turbine is connected to the energy release cycle condenser; the turbine is connected to the generator, and the energy release cycle condenser exchanges heat with the cold medium in the energy storage device through a second heat storage medium loop, and the cold medium exchanges heat to form a heat storage medium, and the low-temperature and low-pressure working fluid forms a liquid second organic working fluid after heat exchange with the cold medium and flows back to the energy release cycle condenser.

[0014] Furthermore, the surface seawater is provided with a surface seawater pump, and the surface seawater pump is used to pump the surface seawater to the charging cycle evaporator.

[0015] Furthermore, the heat storage medium is water or lava.

[0016] The present invention discloses the following technical effects:

[0017] The present invention provides an energy storage system that combines a Carnot battery with ocean thermal energy. During periods of low electricity consumption, the low temperature of deep seawater is used to store excess power from the power grid in the form of a cold medium. During periods of peak electricity consumption, the high temperature of surface seawater is used to generate electricity using a Rankine cycle, and the cold medium stored during the low electricity consumption period is used to condense the Rankine cycle working fluid. This not only fully utilizes the renewable energy advantage of low-grade ocean thermal energy, but also expands the application scenarios of the Carnot battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a schematic diagram of the structure of the present invention;

[0020] Among them, 1. Compressor; 2. Deep seawater pump; 3. Charging cycle condenser; 4. Throttle valve; 5. Charging cycle evaporator; 6. Energy storage device; 7. Energy release cycle condenser; 8. Working fluid pump; 9. Surface seawater pump; 10. Energy release cycle evaporator; 11. Turbine; 12. Generator; 13. Surface seawater; 14. Deep seawater. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] An embodiment of the present invention provides a Carnot battery system driven by ocean temperature difference energy, comprising:

[0024] An energy-charging circulation system is arranged near the deep seawater 14, and a first organic working medium circulates within the system. The energy-charging circulation system is electrically connected to the power grid, and uses excess electricity to drive the first organic working medium to circulate and exchange heat with the deep seawater 14 to form a cold working medium.

[0025] Energy storage device 6, which exchanges heat with the cold working fluid generated by the charging cycle system to form a cold medium and store it;

[0026] The energy release circulation system is arranged close to the surface seawater 13, and the second organic working fluid flows inside it in a Rankine cycle. The second organic working fluid can exchange heat with the surface seawater 13 to form superheated steam. The superheated steam drives the generator 12 to generate electricity and form a low-temperature, low-pressure working fluid. The low-temperature, low-pressure working fluid exchanges heat with the cold medium in the energy storage device 6 and condenses to form a liquid second organic working fluid.

[0027] In this embodiment, the charging cycle system includes: a compressor 1, a charging cycle condenser 3, a throttle valve 4 and a charging cycle evaporator 5, which are connected in sequence. The outlet of the charging cycle evaporator 5 is connected to the compressor 1; the compressor 1 is electrically connected to the power grid, and the charging cycle evaporator 5 exchanges heat with the heat storage medium in the energy storage device 6 through a first heat storage medium loop. The heat storage medium exchanges heat to form a cold medium and stores it. After the cold working fluid exchanges heat with the heat storage medium, it forms a first organic working fluid and flows back to the charging cycle evaporator 5.

[0028] In this embodiment, the deep seawater 14 is provided with a deep seawater pump 2 , and the deep seawater pump 2 is used to pump the deep seawater 14 to the charging cycle condenser 3 .

[0029] In this embodiment, the energy release cycle system includes: an energy release cycle condenser 7, a working fluid pump 8, an energy release cycle evaporator 10 and a turbine 11, which are connected in sequence. The outlet of the turbine 11 is connected to the energy release cycle condenser 7; the turbine 11 is connected to the generator 12, and the energy release cycle condenser 7 exchanges heat with the cold medium in the energy storage device 6 through the second heat storage medium loop. The cold medium exchanges heat to form a heat storage medium. The low-temperature and low-pressure working fluid exchanges heat with the cold medium to form a liquid second organic working fluid and flows back to the energy release cycle condenser 7.

[0030] In this embodiment, a surface seawater pump 9 is arranged for the surface seawater 13 , and the surface seawater pump 9 is used to pump the surface seawater 13 to the charging cycle evaporator 5 .

[0031] In this embodiment, the heat storage medium is water or lava.

[0032] The specific working process is as follows:

[0033] During periods of low electricity demand, the charging cycle system operates in "cooling mode." Renewable energy generation equipment, such as solar and wind power, generates excess electricity. This excess electricity drives compressor 1, compressing the first organic refrigerant at the outlet of the charging cycle evaporator 5, raising its temperature and pressure. This refrigerant then enters the charging cycle condenser 3, where it undergoes heat exchange with deep seawater 14, generating a cold refrigerant. This refrigerant then enters the throttle valve 4 for expansion, then enters the charging cycle evaporator 5 and exchanges heat with the heat storage medium in the heat storage device through the first heat storage medium circuit. The heat storage medium then exchanges heat to form a cold medium, which is then stored. The cold refrigerant then exchanges heat with the heat storage medium to form the first organic refrigerant, which then flows back to the charging cycle evaporator 5, repeating the cycle. At this point, the charging process is complete. Based on the low temperature of deep seawater 14, the system converts excess electricity from the grid into a cold medium, which is then stored in the heat storage device.

[0034] During peak electricity demand periods, the energy release cycle system operates in a Rankine cycle. In the energy release cycle evaporator 10, the second organic working fluid absorbs heat from the surface seawater 13 to form superheated steam. The superheated steam enters the turbine 11, expands, and performs work, driving the generator 12 to generate electricity. After the superheated steam performs work, it forms a low-temperature, low-pressure working fluid. This low-temperature, low-pressure working fluid then enters the energy release cycle condenser 7 to exchange heat with the refrigerant. The refrigerant then forms a heat storage medium. The low-temperature, low-pressure working fluid then forms a liquid second organic working fluid and flows back to the energy release cycle condenser 7, repeating the cycle. At this point, the energy release process is complete, and the system generates electricity based on the high temperature of the surface seawater 13 and the stored refrigerant. This helps to smooth out the peak loads of the power grid.

[0035] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0036] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. Carnot battery system driven by ocean temperature difference, characterized by: include: An energy charging circulation system is arranged near the deep seawater (14), and a first organic working medium circulates in the system. The energy charging circulation system is electrically connected to the power grid, and uses excess electricity to drive the first organic working medium to circulate and exchange heat with the deep seawater (14) to form a cold working medium. An energy storage device (6) exchanges heat with the cold working fluid generated by the charging circulation system to form a cold medium and store it; An energy release circulation system is arranged close to the surface seawater (13), and a second organic working medium flows in the Rankine cycle inside the system. The second organic working medium can exchange heat with the surface seawater (13) to form superheated steam. The superheated steam drives the generator (12) to generate electricity and form a low-temperature, low-pressure working medium. The low-temperature, low-pressure working medium exchanges heat with the cold medium in the energy storage device (6) and condenses to form a liquid second organic working medium.

2. The Carnot battery system driven by ocean temperature difference energy according to claim 1, characterized in that: The charging cycle system comprises: a compressor (1), a charging cycle condenser (3), a throttle valve (4) and a charging cycle evaporator (5) which are connected in sequence, wherein the outlet of the charging cycle evaporator (5) is connected to the compressor (1); the compressor (1) is electrically connected to the power grid; the charging cycle evaporator (5) exchanges heat with the heat storage medium in the energy storage device (6) through a first heat storage medium loop; the heat storage medium forms a cold medium through heat exchange and is stored; the cold working medium forms a first organic working medium after heat exchange with the heat storage medium and flows back to the charging cycle evaporator (5).

3. The Carnot battery system driven by ocean temperature difference energy according to claim 2, characterized in that: The deep seawater (14) is provided with a deep seawater pump (2), and the deep seawater pump (2) is used to pump the deep seawater (14) to the charging cycle condenser (3).

4. The Carnot battery system driven by ocean temperature difference energy according to claim 2 or 3, characterized in that: The energy release circulation system includes: an energy release circulation condenser (7), a working fluid pump (8), an energy release circulation evaporator (10) and a turbine (11) which are connected in sequence. The outlet of the turbine (11) is connected to the energy release circulation condenser (7); the turbine (11) is connected to the generator (12); the energy release circulation condenser (7) exchanges heat with the cold medium in the energy storage device (6) through a second heat storage medium loop, the cold medium forms a heat storage medium through heat exchange, and the low-temperature and low-pressure working fluid forms a liquid second organic working fluid after heat exchange with the cold medium and flows back to the energy release circulation condenser (7).

5. The Carnot battery system driven by ocean temperature difference energy according to claim 4, characterized in that: The surface seawater (13) is provided with a surface seawater pump (9), and the surface seawater pump (9) is used to pump the surface seawater (13) to the charging circulation evaporator (5).

6. The Carnot battery system driven by ocean temperature difference energy according to claim 4, characterized in that: The heat storage medium is water or lava.

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