New energy and pneumoelectric coupled low-carbon-based charge source

Abstract

The utility model provides a new energy and gas-electricity coupled low-carbon-based charge source which comprises a new energy power generation field, a fused salt heat storage system, a gas power station and a power generation system. The fused salt heat storage system is of a cold and hot tank circulation structure, and the new energy power plant is connected with the fused salt heat storage system through the first heat exchange unit. The fused salt heat storage system is connected with the power generation system through the second heat exchange unit; the gas power station is connected with the power generation system through the third heat exchange unit. According to the utility model, energy conversion and space-time translation of heat energy are realized through new energy heat exchange coupling and fused salt heat storage technologies, so that a stable base charge power supply is formed; wherein the gas unit is used as a flexible adjusting power supply, and is used for quickly responding when the new energy output is suddenly reduced or the load is suddenly increased so as to make up a power gap; according to the cooperative operation mode, the flexibility advantage of gas power generation is brought into play, the dependence degree on gas resources is reduced through new energy replacement, meanwhile, overall carbon emission reduction of the system is achieved, and the system conforms to the clean, low-carbon, safe and efficient energy development direction.

Description

A low-carbon baseload power source that couples new energy sources with gas electricity Technical Field

[0001] This utility model relates to the field of new energy power supply system technology, specifically to a low-carbon base load power supply that couples new energy with gas electricity. Background Technology

[0002] Against the backdrop of global demand for low-carbon energy, building a new power system dominated by new energy sources has become a key objective. However, with the continuous increase in the penetration rate of renewable energy generation such as wind and solar power, their inherent randomness, volatility, and intermittency pose serious challenges to the frequency stability, active power balance, and flexible regulation capabilities of the power system. Specifically, this manifests as: high-proportion renewable energy integration leading to reduced system inertia, shortage of frequency regulation resources, increased risk of power curtailment, and the inability of traditional power supply structures based on synchronous machines to adapt to the operational requirements of high-proportion renewable energy and high-power electronic equipment systems. How to improve the renewable energy absorption capacity and maintain system safety and stability while ensuring power supply reliability has become a key technical challenge in the current power sector.

[0003] Gas-fired power generation, with its rapid start-up and shutdown, wide load regulation range, and high active power response rate, has become an ideal transitional power source for bridging the high proportion of renewable energy consumption. Its flexible regulation capabilities can effectively smooth out fluctuations in renewable energy output, playing a crucial role in scenarios such as load peak-valley regulation and system black start. Simultaneously, the rapid response characteristics of gas-fired units can match short-term power fluctuations from renewable energy sources, reducing curtailment losses and enhancing the power system's inclusiveness towards renewable energy.

[0004] However, the sustainable development of gas-fired power generation faces significant constraints. On the one hand, the dependence on imported gas resources is relatively high, posing a significant risk to energy supply security. On the other hand, increased volatility in energy market prices has led to high costs for gas-fired power generation, making it uneconomical to use it as a large-scale baseload power source. Furthermore, gas-fired power generation still falls under the category of carbon-based energy, with high carbon emission intensity, falling short of the requirements for deep decarbonization of the power structure under carbon reduction goals. Therefore, traditional gas-fired power generation is unlikely to become the main power source in the new power system, and its development needs to shift towards low-carbon, flexible, and collaborative approaches.

[0005] Against this backdrop, existing technologies have developed various types of energy complementary and integrated models. These models organically couple traditional energy units with new energy sources and energy storage systems to construct a synergistically regulated integrated energy system. However, the current benchmark for energy coupling is generally electrical coupling. While this approach offers fast response and ease of adjustment, it struggles to maintain stable system output over extended periods in scenarios with large fluctuations. Furthermore, the applied electrical energy storage units suffer from high costs and short lifespans, hindering their large-scale application.

[0006] In summary, it is necessary to integrate and improve the existing power supply units to achieve low-carbon coupling, thereby ensuring system stability while effectively controlling operating costs. Summary of the Invention

[0007] This utility model addresses the problems existing in the prior art by providing a new energy and gas-electric coupling low-carbon base load power supply that is simple to build and implement, has low operating costs, and can provide stable power supply.

[0008] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0009] This utility model provides a low-carbon baseload power source that couples new energy with gas and electricity, which mainly includes a new energy power plant, a molten salt thermal storage system, a gas power plant and a power generation system;

[0010] The molten salt thermal storage system has a hot and cold tank circulation structure. The new energy power plant is connected to the molten salt thermal storage system through a first heat exchange unit; the molten salt thermal storage system is connected to the power generation system through a second heat exchange unit.

[0011] The gas-fired power plant is connected to the power generation system via a third heat exchange unit.

[0012] Optionally, the new energy power plant includes at least a wind farm;

[0013] The wind farm is connected to the first heat exchange unit via an electric heating system, which is used to convert wind power into heat energy and input it into the molten salt thermal storage system.

[0014] The wind farm is also connected to the power grid for grid-connected power generation compensation.

[0015] Optionally, the new energy power plant includes a solar thermal power plant;

[0016] The heat output terminal of the solar thermal power plant is connected to the first heat exchange unit to input heat energy into the molten salt thermal storage system.

[0017] Optionally, the molten salt thermal storage system includes a cold molten salt storage tank and a hot molten salt storage tank;

[0018] The cold molten salt storage tank and the hot molten salt storage tank are connected by a circulation loop, and the circulation loop is respectively provided with a heat storage loop and a heat release loop;

[0019] The first heat exchange unit is connected to the heat storage circuit for heat exchange;

[0020] The second heat exchange unit is connected to the heat dissipation circuit for heat exchange.

[0021] Optionally, the cold molten salt storage tank and / or the hot molten salt storage tank adopt a structure of multiple tanks connected in parallel;

[0022] In the molten salt thermal storage system, the molten salt tanks do not all have the same volume.

[0023] Optionally, the power generation system includes a steam turbine, a generator, and a steam turbine circulation pipeline;

[0024] The steam turbine drives the generator to generate electricity, which is then connected to the power grid via a power supply circuit.

[0025] Both the second and third heat exchange units are connected to the steam turbine.

[0026] Optionally, a waste heat boiler is provided on the turbine circulation pipeline; the second and third heat exchange units are provided on the steam pipeline between the waste heat boiler and the turbine.

[0027] Optionally, the second heat exchange unit and the third heat exchange unit are connected in parallel.

[0028] Optionally, the flue gas system of the gas-fired power plant is equipped with a waste heat recovery device, and the waste heat recovery device is connected to the third heat exchange unit to input the recovered flue gas waste heat into the power generation system.

[0029] Optionally, the gas-fired power plant is connected to the power grid via a power supply circuit for direct grid-connected power generation.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This invention utilizes new energy heat exchange coupling and molten salt thermal storage technology to achieve energy conversion and spatiotemporal transfer of thermal energy. It stores excess energy during periods of ample sunlight and releases thermal energy during periods of low output to drive a steam turbine for power generation, forming a stable baseload power source. The gas turbine unit acts as a flexible power source, responding quickly to sudden drops in new energy output or load surges to compensate for power shortfalls. This collaborative operation mode leverages the flexibility of gas-fired power generation while reducing dependence on gas resources through new energy substitution, achieving overall carbon emission reduction and aligning with the clean, low-carbon, safe, and efficient energy development direction. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 is a simplified system diagram in a specific embodiment of this utility model.

[0034] In the diagram: 1. New energy power plant; 2. Molten salt thermal storage system; 3. Power generation system; 4. Gas power plant; 5. First heat exchange unit; 6. Second heat exchange unit; 7. Third heat exchange unit; 101. Solar thermal power plant; 102. Wind farm; 201. Cold molten salt storage tank; 202. Hot molten salt storage tank; 301. Waste heat boiler; 302. Steam turbine; 303. Generator. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0036] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0037] In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0038] It is worth noting that, unless otherwise specified, the methods used in this utility model are all conventional methods; and the raw materials and equipment used are all conventional commercially available products, and their sources are not specifically limited.

[0039] The low-carbon baseload power source coupled with new energy and gas power provided in this embodiment mainly includes a new energy power plant 1, a molten salt thermal storage system 2, a power generation system 3, and a gas power plant 4.

[0040] Among them, the new energy power plant 1 is a wind and solar power plant. Taking the solar thermal power plant 101 and the wind farm 102 as examples, as shown in Figure 1. The solar thermal power plant 101 focuses solar energy onto the vacuum collector tube by adjusting the mirror angle in real time. The heat transfer medium in the collector tube, such as heat transfer oil or molten salt, absorbs the heat energy and is then transported to the first heat exchange unit 5 through pipelines.

[0041] The first heat exchange unit 5 realizes the heat exchange between the solar thermal working fluid and the cold molten salt in the molten salt storage system 2. The control system of the solar thermal power plant 101 integrates a weather forecast module, which can automatically adjust the mirror angle to a safe position before extreme weather arrives and start the anti-freeze cycle, maintaining the fluidity of the working fluid through electric heat tracing.

[0042] The capacity of each wind turbine in wind farm 102 is selected based on site conditions. The wind turbines achieve variable-speed, constant-frequency power generation through a full-power converter. Part of the output power can be directly connected to the grid, while the other part, after being converted to industrial frequency by a high-voltage frequency converter, can drive the electric heating system. This allows wind power to directly connect to the grid and provide clean electricity when electricity demand is high or sunlight intensity is low, thus compensating for the missing power generation. When electricity demand is low or sunlight intensity is high, wind power can be converted into heat energy and stored in the molten salt thermal storage system. The electric heating system uses resistance or induction heating elements to convert electrical energy into heat energy, and the heated working fluid is transported to the first heat exchange unit 5 via a working fluid circulation pump for secondary heat exchange with the cold molten salt. The power distribution of wind farm 102 is dynamically adjusted by an intelligent control system based on grid load, sunlight intensity, and thermal storage status, achieving rapid switching between "grid-connected power generation" and "thermal storage power supply" modes through a power electronic switch matrix.

[0043] The molten salt thermal energy storage system 2 adopts a dual-tank circulation structure. When the power system load is high, the molten salt thermal energy storage system releases heat to drive the steam turbine for power generation; when the load is low, the molten salt thermal energy storage system stores thermal energy. The cold molten salt storage tank 201 and the hot molten salt storage tank 202 are connected by a molten salt circulation pump set. In the thermal energy storage loop, the first heat exchange unit 5 transfers heat generated by solar thermal and wind power to the cold molten salt, raising its temperature before storing it in the hot molten salt storage tank 202. In the heat release loop, the hot molten salt exchanges heat with water through the second heat exchange unit 6, generating high-temperature, high-pressure steam to drive the power generation system 3. The second heat exchange unit 6 achieves counter-current heat exchange between the molten salt and water, improving thermal efficiency. The third heat exchange unit 7 is connected in series with the waste heat recovery device of the gas-fired power plant 4 to further recover waste heat from the flue gas, improving the overall energy efficiency of the system.

[0044] In another embodiment, the cold molten salt storage tank 201 and the hot molten salt storage tank 202 can be configured as multiple tanks connected in parallel according to energy storage requirements, with each tank achieving pressure equalization through a balancing pipe. Each tank is equipped with an independent temperature sensor array and radar level gauge to monitor the molten salt status in real time. For scenarios with large fluctuations, the system adopts a stepped volume ratio design, with the total volume of the cold tanks greater than the total volume of the hot tanks, to cope with the intermittent nature of new energy output.

[0045] Power generation system 3 is a reheat steam turbine generator set, comprising a steam turbine 302, a generator 303, and a turbine circulation pipeline. The steam turbine 302 drives the generator 303 to generate electricity, which is then connected to the power grid via a power supply circuit. The main steam parameters of power generation system 3 are determined according to the system design. The turbine circulation pipeline adopts a three-stage regenerative system, including a high-pressure heater, a deaerator, and a low-pressure heater, improving system efficiency through feedwater reheating. Waste heat boiler 301 serves as an auxiliary heat source, connected in parallel with the main steam pipeline via a four-way reversing valve. When the molten salt thermal storage system 2 supplies power independently, the waste heat boiler 301 is in standby mode; when a rapid load increase is required, the waste heat boiler 301 can also incorporate waste heat from the flue gas of the gas-fired power plant 4 to supplement the steam volume. The steam turbine 302 is equipped with a digital electro-hydraulic control system to achieve precise speed and load regulation, with a load response rate meeting the grid's peak-shaving requirements.

[0046] Gas-fired power plant 4 is also connected to the power grid via a power supply circuit for direct grid-connected power generation. Its compressor adopts an axial-flow multi-stage design, with an inlet filter separator to prevent dust particles from entering the system. The combustion chamber supports the co-firing of natural gas and hydrogen, and the fuel composition is monitored in real time through an online laser spectroscopy analysis system. The flue gas waste heat recovery device adopts a three-pressure reheat system, sequentially recovering heat from high-temperature, medium-temperature, and low-temperature flue gas to generate steam with different parameters. Waste heat boiler 301 is connected to the gas turbine exhaust system via a flue. After multi-stage heat exchange, the flue gas is finally treated through environmental protection to ensure that pollutant emissions meet standards.

[0047] The integrated energy management system adopts a hierarchical distributed control architecture. The field control layer implements device-level control through PLCs, the coordination layer generates scheduling plans based on model predictive control algorithms, and the optimization layer solves for the optimal energy allocation scheme with the minimum system operating cost as the objective function. The multi-source collaborative operation strategy includes a solar thermal priority mode, a thermal energy storage and release mode, and an extreme weather mode. In the solar thermal priority mode, the solar thermal power plant 101 provides full power, the wind farm 102 is connected to the grid only during peak load periods, and surplus electricity is used for thermal energy storage. In the thermal energy storage and release mode, the system relies on the molten salt thermal energy storage system 2 for power supply, and the gas-fired power plant 4 is in a hot standby state. In the extreme weather mode, the system switches to a "gas-electric base load + thermal energy storage peak shaving" mode to ensure power supply reliability.

[0048] Through the aforementioned technological optimizations, the system achieves deep coupling of solar thermal, wind power, gas power, and thermal storage, significantly improving overall energy utilization and low-carbon performance while maintaining flexibility and stability. The system can flexibly switch between baseload generation and peak-shaving modes according to grid demand, providing reliable support for a high proportion of new energy power systems and promoting the transformation of the energy structure towards clean and low-carbon practices.

[0049] In this embodiment of the invention, the novel low-carbon baseload power supply scheme innovatively couples a gas-fired power plant with a solar thermal power plant and a wind farm, enabling multi-energy coupling and comprehensive optimized scheduling of "gas-fired power + new energy" unit combinations. Specifically:

[0050] (1) The wind farm is connected to the solar thermal power plant through a heat exchanger to provide energy to the lava thermal storage system according to the sunlight conditions, or directly connect to the grid to generate electricity according to the power system's electricity demand;

[0051] (2) The gas-fired power plant and the solar thermal power plant share the same power generation system. The waste heat of the internal combustion engine flue gas is recovered and utilized through the heat exchanger, which improves the overall efficiency of the entire energy supply system and realizes multi-level energy utilization. At the same time, it can provide a guaranteed power supply according to the system's power demand to make up for the instability of solar thermal and wind power output.

[0052] Comparative Example 1;

[0053] Consider replacing a 600MW gas-fired power plant in a certain region with the novel low-carbon baseload power scheme described in the aforementioned embodiments. Specifically, replace the pure gas-fired power scheme of 420MW gas turbine and 180MW steam turbine with a "gas-fired power + new energy" configuration combining a 300MW gas turbine, a 200MW steam turbine, 600MW wind power, 200MW solar thermal power, and 1600MWh molten salt thermal storage, all with equivalent output. The comparison results are shown in Table 1 below:

[0054] Table 1

[0055]

[0056] Based on the information in the table above, we can conclude that:

[0057] From an economic perspective, the cost per kilowatt-hour in this embodiment is 0.36 yuan / kWh, which is the same as the cost per kilowatt-hour of the original scheme.

[0058] Regarding fuel costs, the natural gas consumption of this embodiment is 221 million cubic meters, which is about 30% of the natural gas consumption of the original embodiment 1. The new low-carbon baseload power supply scheme of this embodiment significantly reduces fuel costs compared with the pure gas-fired power scheme.

[0059] From the perspective of power supply reliability, the expected energy deficit (EENS) of this embodiment is 4862 MWh / year, and the EENS accounts for about 0.1% of the theoretical output of the system. The system operation stability of the new low-carbon baseload power supply scheme is relatively high.

[0060] Finally, it should be noted that the above content is only used to illustrate the technical solution of this utility model, and is not intended to limit the scope of protection of this utility model. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model do not depart from the essence and scope of the technical solution of this utility model.

Claims

1. A low-carbon baseload power source that couples new energy sources with gas electricity, characterized in that: It includes a new energy power plant, a molten salt thermal storage system, a gas-fired power plant, and a power generation system; the molten salt thermal storage system has a hot and cold tank circulation structure; the new energy power plant is connected to the molten salt thermal storage system through a first heat exchange unit; the molten salt thermal storage system is connected to the power generation system through a second heat exchange unit; and the gas-fired power plant is connected to the power generation system through a third heat exchange unit.

2. The low-carbon baseload power source coupled with new energy and gas power according to claim 1, characterized in that: The new energy power plant includes at least a wind farm; the wind farm is connected to the first heat exchange unit via an electric heating system; the wind farm is also connected to the power grid.

3. The low-carbon baseload power source coupled with new energy and gas power according to claim 1 or 2, characterized in that: The new energy power plant includes a solar thermal power plant; the heat output end of the solar thermal power plant is connected to the first heat exchange unit.

4. The low-carbon baseload power source coupled with new energy and gas-electricity as described in claim 1, characterized in that: The molten salt thermal storage system includes a cold molten salt storage tank and a hot molten salt storage tank; the cold molten salt storage tank and the hot molten salt storage tank are connected through a circulation loop, and the circulation loop is respectively provided with a thermal storage loop and a thermal release loop; the first heat exchange unit is connected to the thermal storage loop for heat exchange; the second heat exchange unit is connected to the thermal release loop for heat exchange.

5. The low-carbon baseload power supply coupled with new energy and gas power according to claim 4, characterized in that: The cold molten salt storage tank and / or the hot molten salt storage tank adopt a multi-tank parallel structure; in the molten salt thermal storage system, the molten salt tanks are not all the same volume.

6. The low-carbon baseload power supply coupled with new energy and gas power according to claim 1, characterized in that: The power generation system includes a steam turbine, a generator, and a steam turbine circulation pipeline; the steam turbine drives the generator to generate electricity and is connected to the power grid through a power supply circuit; the second and third heat exchange units are both connected to the steam turbine.

7. The low-carbon baseload power source coupled with new energy and gas-electricity as described in claim 6, characterized in that: A waste heat boiler is installed on the turbine circulation pipeline; the second and third heat exchange units are installed on the steam pipeline between the waste heat boiler and the turbine.

8. The low-carbon baseload power supply coupled with new energy and gas power according to claim 7, characterized in that: The second heat exchange unit and the third heat exchange unit are connected in parallel.

9. The low-carbon baseload power source coupled with new energy and gas power according to claim 1, characterized in that: The flue gas system of the gas power plant is equipped with a waste heat recovery device, which is connected to the third heat exchange unit.

10. The low-carbon baseload power source coupled with new energy and gas as described in claim 1 or 9, characterized in that: The gas-fired power plant is connected to the power grid via a power supply circuit.

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