Distributed energy supply system integrating solar assisted chemical looping reforming and fuel cell

Abstract

This invention discloses a distributed energy supply system integrating solar-assisted chemical loop reforming and a fuel cell, comprising a solar-assisted chemical loop reforming subsystem, a proton exchange membrane fuel cell subsystem, a chemical loop combustion subsystem, an absorption refrigeration subsystem, and a thermal energy storage subsystem. The system utilizes a concentrating photovoltaic (PV) thermal collector to capture solar energy, preheat the fuel, and generate electricity. The preheated fuel undergoes chemical loop reforming to produce hydrogen-rich reformed gas, which is then supplied to the fuel cell for efficient power generation. The fuel cell anode exhaust gas enters the fuel reactor of the chemical loop combustion subsystem, where lattice oxygen is provided by an oxygen carrier to achieve nitrogen-free dilution oxidation, generating product gas mainly composed of CO2 and H2O. The product gas is cooled, condensed, and dehydrated before being output with CO2 enrichment, and can optionally enter a buffer tank / compression unit. The system recovers waste heat from the fuel cell and the high-temperature flue gas from chemical loop combustion through a closed-loop heat transfer oil system, storing the waste heat in high- and low-temperature heat transfer oil tanks to provide a stable heat source for absorption refrigeration.

Description

Technical Field

[0001] This invention relates to the field of distributed energy and advanced power cycle technology, and in particular to a distributed energy supply system that integrates solar-assisted chemical chain reforming and fuel cells. Background Technology

[0002] With the advancement of global "dual carbon" goals, the installed capacity of renewable energy sources such as solar power is growing rapidly. However, the intermittency and volatility of solar energy make it difficult for energy supply systems relying solely on solar power to achieve stable and dispatchable output. Fuel cells have the advantages of high efficiency and low pollution, making them suitable for distributed energy supply. However, traditional high-pressure hydrogen production, storage, transportation, and safety costs are high. If hydrogen is produced by reforming carbon-containing fuels, additional combustion heating is usually required, resulting in significant carbon emissions. Furthermore, carbon dioxide capture often relies on energy-intensive back-end separation.

[0003] Existing solutions generally suffer from insufficient coordination in "solar energy conversion, low-carbon hydrogen production, exhaust gas treatment and carbon capture, and waste heat cascade utilization", resulting in low overall energy efficiency, poor adaptability to solar fluctuations, and difficulty in achieving efficient integrated supply of cooling, heating and electricity. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a distributed energy supply system integrating solar-assisted chemical reforming and fuel cells. This system solves the technical problems of large fluctuations in renewable energy, high carbon emissions from traditional hydrogen production, and low overall energy utilization in existing technologies. It achieves cascade complementarity between solar energy and fuel chemical energy, realizes nitrogen-free dilution oxidation of exhaust gas at the reactor level to form enriched carbon dioxide, and achieves stable operation under all operating conditions through heat storage and control strategies.

[0005] The objective of this invention is achieved as follows: a distributed energy supply system integrating solar-assisted chemical loop reforming and fuel cells, comprising a solar-assisted chemical loop reforming subsystem, a proton exchange membrane fuel cell subsystem, a chemical loop combustion subsystem, an absorption refrigeration subsystem, and a thermal energy storage subsystem; The solar-assisted chemical reforming subsystem includes a concentrating photovoltaic thermal collector, a photovoltaic inverter unit, a fuel reforming reactor, and an air oxidation reactor. The first air heat exchanger is included; the electrical output terminal of the concentrating photovoltaic thermal collector is connected to the photovoltaic inverter unit, and its heat working fluid outlet is connected to the fuel inlet of the fuel reforming reactor; the fuel outlet of the fuel reforming reactor is connected to the proton exchange membrane fuel cell subsystem; an oxygen carrier circulation pipeline is provided between the fuel reforming reactor and the air oxidation reactor; external air enters the air oxidation reactor after being preheated by the first air heat exchanger, and the exhaust outlet of the air oxidation reactor is connected to the hot side inlet of the first air heat exchanger. The proton exchange membrane fuel cell subsystem includes a fuel cooler, a proton exchange membrane fuel cell stack, a DC / AC inverter unit, a cathode air preheater, and a thermal oil distributor. The fuel is connected to the fuel outlet of the fuel reforming reactor via the hot-side inlet of the fuel cooler, and to the anode inlet of the proton exchange membrane fuel cell stack via the hot-side outlet of the fuel cooler. The anode outlet of the proton exchange membrane fuel cell stack is connected to the chemical looping combustion subsystem. The cathode exhaust outlet of the proton exchange membrane fuel cell stack is connected to the hot-side inlet of the cathode air preheater, and external air enters the cathode inlet of the proton exchange membrane fuel cell stack after being preheated by the cathode air preheater. The low-temperature thermal oil outlet of the thermal energy storage subsystem is connected to the thermal oil distributor. The first outlet of the thermal oil distributor is connected to the cold-side inlet of the fuel cooler, and the second outlet is connected to the cooling channel inlet of the proton exchange membrane fuel cell stack. The thermal oil outlets of the fuel cooler and the proton exchange membrane fuel cell stack merge and connect to the chemical looping combustion subsystem. The chemical loop combustion subsystem (3) includes a fuel reactor, an air reactor, a heat exchanger, an air mixer, and a second air heat exchanger. The fuel inlet of the fuel reactor is connected to the anode outlet of the proton exchange membrane fuel cell stack. The anode exhaust gas from the proton exchange membrane fuel cell stack enters the fuel reactor and undergoes a reduction reaction with the internal oxygen carrier. The high-temperature exhaust outlet of the fuel reactor is connected to the hot-side inlet of the heat exchanger, and the cold-side outlet of the fuel cooler is connected to the cold-side inlet of the heat exchanger. After absorbing heat and heating up, the fuel flows to the thermal energy storage subsystem. The first inlet of the air mixer is connected to the exhaust outlet of the cathode air preheater of the proton exchange membrane fuel cell subsystem. The external air is preheated by the second air heat exchanger and then connected to the second inlet of the air mixer. The outlet of the air mixer is connected to the air inlet of the air reactor, and the exhaust outlet of the air reactor is connected to the hot-side inlet of the second air heat exchanger. An oxygen carrier circulation pipeline is provided between the fuel reactor and the air reactor.

[0006] Furthermore, the absorption refrigeration subsystem includes a condenser, a first throttling valve, a low-pressure generator, a high-pressure generator, a high-temperature solution heat exchanger, a second throttling valve, a first solution pump, a diverter valve, a low-temperature solution heat exchanger, a third throttling valve, a second solution pump, an absorber, a cooling water pump, a cooling tower, a fourth throttling valve, an evaporator, and a chilled water regulating valve; the heat source inlet of the high-pressure generator is connected to the outlet of the high-temperature heat transfer oil tank of the thermal energy storage subsystem; the heat source outlet of the high-pressure generator is connected to the outlet of the low-temperature heat transfer oil tank of the thermal energy storage subsystem; the vapor phase outlet of the high-pressure generator is connected to the condenser inlet after passing through the low-pressure generator and the first throttling valve; the vapor phase outlet of the condenser is connected to the evaporator inlet after passing through the fourth throttling valve. The evaporator outlet is connected to the absorber inlet. The absorber outlet, after passing through a second solution pump and a low-temperature solution heat exchanger, is connected to the inlet of a diversion valve. The diversion valve then splits the absorber into two paths: one path connects to the low-pressure generator inlet, and the other path, after passing through a first solution pump and a high-temperature solution heat exchanger, connects to the high-pressure generator inlet. The liquid phase outlet of the high-pressure generator, after passing through a high-temperature solution heat exchanger and a second throttle valve, connects to the low-pressure generator inlet. The liquid phase outlet of the low-pressure generator, after passing through a low-temperature solution heat exchanger and a third throttle valve, connects to the absorber inlet. The gas phase outlet of the low-pressure generator connects to the condenser inlet. The cooling tower outlet, after passing through a cooling water pump, absorber, and condenser, connects to the cooling tower inlet. Chilled water return is supplied to users after passing through a chilled water regulating valve.

[0007] Furthermore, the thermal energy storage subsystem includes a low-temperature thermal oil storage tank, an air mixer, a waste heat recovery heat exchanger, a thermal oil mixer, and a high-temperature thermal oil storage tank; the exhaust outlets of the first and second air heat exchangers are respectively connected to the inlet of the air mixer; the outlet of the air mixer is connected to the hot-side inlet of the waste heat recovery heat exchanger; the thermal oil outlet of the heat exchanger is connected to the thermal oil mixer, and the outlet of the thermal oil mixer is connected to the high-temperature thermal oil storage tank; the outlet of the high-temperature thermal oil storage tank is connected to the heat source inlet of the high-pressure generator of the absorption refrigeration subsystem, and the heat source outlet of the high-pressure generator is connected to the low-temperature thermal oil storage tank; the outlet of the low-temperature thermal oil storage tank is connected to the thermal oil splitter of the proton exchange membrane fuel cell subsystem.

[0008] Furthermore, the fuel reforming reactor uses methanol, ethanol, or natural gas as carbon-containing fuel, and the oxygen carrier is one of the CuO / Cu, Fe2O3 / Fe3O4, or NiO / Ni systems or a composite system thereof.

[0009] Furthermore, the thermal energy storage subsystem is a dual-tank sensible heat energy storage structure, and the heat transfer oil is biphenyl-biphenyl ether, silicone oil, or a heat transfer oil product.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) Smoothing fluctuations and stabilizing output: By using the cascade coupling of solar thermal energy and chemical energy of chemical fuels, and the dual regulation mechanism of chemical loop combustion and thermal energy storage subsystems, the random fluctuations of solar energy are effectively smoothed out, and the reliability of the system's energy supply is improved.

[0011] 2) Source emission reduction and low-consumption carbon capture: The chemical loop combustion subsystem replaces the traditional afterburner. While treating the fuel cell exhaust gas, the internal separation characteristics of the oxygen carrier prevent the mixing of nitrogen in the air. High-purity carbon dioxide can be enriched and captured at the source without additional energy consumption and separation equipment.

[0012] 3) Cascaded utilization with significant energy efficiency: A full-temperature energy utilization network has been constructed, from high-temperature chemical looping combustion (800℃+), medium-temperature reforming (200-300℃) to low-temperature battery waste heat (150-120℃). Through the thermal energy storage subsystem, heat can be flexibly allocated to drive cooling or heating, which significantly reduces system losses and greatly improves the utilization rate of primary energy. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0014] Figure 1 This is a system structure diagram of the present invention.

[0015] The system comprises: 1. A solar-assisted chemical loop reforming subsystem, consisting of 101 a concentrating photovoltaic thermal collector, 102 a photovoltaic inverter unit, 103 a fuel reforming reactor, 104 an air oxidation reactor, and 105 a first air heat exchanger; 2. A proton exchange membrane fuel cell subsystem, consisting of 201 a fuel cooler, 202 a proton exchange membrane fuel cell stack, 203 a DC / AC inverter unit, 204 a cathode air preheater, and 205 a thermal oil distributor; 3. A chemical loop combustion subsystem, consisting of 301 a fuel reactor, 302 an air reactor, 303 a heat exchanger, 304 an air mixer, and 305 a second air heat exchanger; and 4. An absorption refrigeration subsystem. 401 Condenser, 402 First throttle valve, 403 Low-pressure generator, 404 High-pressure generator, 405 High-temperature solution heat exchanger, 406 Second throttle valve, 407 First solution pump, 408 Diverter valve, 409 Low-temperature solution heat exchanger, 410 Third throttle valve, 411 Second solution pump, 412 Absorber, 413 Cooling water pump, 414 Cooling tower, 415 Fourth throttle valve, 416 Evaporator, 417 Chilled water regulating valve; 5 Thermal energy storage subsystem, 501 Low-temperature thermal oil storage tank, 502 Air mixer, 503 Waste heat recovery heat exchanger, 504 Thermal oil mixer, 505 High-temperature thermal oil storage tank. Detailed Implementation

[0016] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] like Figure 1 The distributed energy supply system integrating solar-assisted chemical reforming and fuel cells shown includes a solar-assisted chemical reforming subsystem 1, a proton exchange membrane fuel cell subsystem 2, a chemical combustion subsystem 3, an absorption refrigeration subsystem 4, and a thermal energy storage subsystem 5. The solar-assisted chemical loop reforming subsystem 1 includes a concentrating photovoltaic thermal collector 101, a photovoltaic inverter unit 102, a fuel reforming reactor 103, an air oxidation reactor 104, and a first air heat exchanger 105. The electrical output terminal of the concentrating photovoltaic thermal collector 101 is connected to the photovoltaic inverter unit 102, and its heat working fluid outlet is connected to the fuel inlet of the fuel reforming reactor 103. The fuel outlet of the fuel reforming reactor 103 is connected to the proton exchange membrane fuel cell subsystem 2. An oxygen carrier circulation pipeline is provided between the fuel reforming reactor 103 and the air oxidation reactor 104. External air enters the air oxidation reactor 104 after being preheated by the first air heat exchanger 105, and the exhaust outlet of the air oxidation reactor 104 is connected to the hot side inlet of the first air heat exchanger 105. The proton exchange membrane fuel cell subsystem 2 includes a fuel cooler 201, a proton exchange membrane fuel cell stack 202, a DC / AC inverter unit 203, a cathode air preheater 204, and a heat transfer oil distributor 205. Fuel is connected to the fuel outlet of the fuel reforming reactor 103 via the hot-side inlet of the fuel cooler 201, and to the anode inlet of the proton exchange membrane fuel cell stack 202 via the hot-side outlet of the fuel cooler 201. Fuel from the solar-assisted chemical looping reforming subsystem 1 enters the anode inlet of the proton exchange membrane fuel cell stack 202 after passing through the fuel cooler 201. The anode outlet of the proton exchange membrane fuel cell stack 202 is connected to the chemical looping reforming subsystem 1. The proton exchange membrane fuel cell stack 202 has a cathode exhaust outlet connected to the hot side inlet of the cathode air preheater 204. External air is preheated by the cathode air preheater 204 and then enters the cathode inlet of the proton exchange membrane fuel cell stack 202. The thermal energy storage subsystem 5 has a low-temperature heat transfer oil outlet connected to a heat transfer oil distributor 205. The first outlet of the heat transfer oil distributor 205 is connected to the cold side inlet of the fuel cooler 201, and the second outlet is connected to the cooling channel inlet of the proton exchange membrane fuel cell stack 202. The heat transfer oil outlets of the fuel cooler 201 and the proton exchange membrane fuel cell stack 202 merge and are then connected to the chemical looping combustion subsystem 3. The chemical loop combustion subsystem (3) includes a fuel reactor 301, an air reactor 302, a heat exchanger 303, an air mixer 304, and a second air heat exchanger 305. The fuel inlet of the fuel reactor 301 is connected to the anode outlet of the proton exchange membrane fuel cell stack 202. The anode exhaust gas from the proton exchange membrane fuel cell stack 202 enters the fuel reactor 301 and undergoes a reduction reaction with the internal oxygen carrier. The high-temperature exhaust outlet of the fuel reactor 301 is connected to the hot-side inlet of the heat exchanger 303. The combined heat transfer oil outlet of the proton exchange membrane fuel cell subsystem 2 is connected to the cold-side inlet of the heat exchanger 303. The combined heat transfer oil of fuel cell subsystem 2 enters the cold side inlet of heat exchanger 303, absorbs heat and is heated before flowing to thermal energy storage subsystem 5. The first inlet of air mixer 304 is connected to the exhaust outlet of cathode air preheater 204 of proton exchange membrane fuel cell subsystem 2. External air is preheated by second air heat exchanger 305 and then connected to the second inlet of air mixer 304. The outlet of air mixer 304 is connected to the inlet of air reactor 302, and the exhaust outlet of air reactor 302 is connected to the hot side inlet of second air heat exchanger 305. An oxygen carrier circulation pipeline is provided between fuel reactor 301 and air reactor 302. Fuel reforming reactor 103 uses methanol, ethanol or natural gas as carbon-containing fuel, and the oxygen carrier is one of CuO / Cu, Fe2O3 / Fe3O4 or NiO / Ni systems or a composite system.

[0018] The absorption refrigeration subsystem 4 includes a condenser 401, a first throttle valve 402, a low-pressure generator 403, a high-pressure generator 404, a high-temperature solution heat exchanger 405, a second throttle valve 406, a first solution pump 407, a flow divider valve 408, a low-temperature solution heat exchanger 409, a third throttle valve 410, a second solution pump 411, an absorber 412, a cooling water pump 413, a cooling tower 414, a fourth throttle valve 415, an evaporator 416, and a chilled water regulator. Valve 417; the heat source inlet of the high-pressure generator 404 is connected to the outlet of the high-temperature heat transfer oil storage tank 505 of the thermal energy storage subsystem 5; the heat source outlet of the high-pressure generator 404 is connected to the outlet of the low-temperature heat transfer oil storage tank 501 of the thermal energy storage subsystem 5; the gas phase outlet of the high-pressure generator 404 is connected to the inlet of the condenser 401 after passing through the low-pressure generator 403 and the first throttle valve 402; the gas phase outlet of the condenser 401 is connected to the inlet of the evaporator 416 after passing through the fourth throttle valve 415. The outlet of evaporator 416 is connected to the inlet of absorber 412. The outlet of absorber 412 is connected to the inlet of diversion valve 408 after passing through second solution pump 411 and low-temperature solution heat exchanger 409. After passing through diversion valve 408, it is divided into two paths: one path is connected to the inlet of low-pressure generator 403, and the other path is connected to the inlet of high-pressure generator 404 after passing through first solution pump 407 and high-temperature solution heat exchanger 405. The liquid phase outlet of high-pressure generator 404 is connected to the inlet of low-pressure generator 403 after passing through high-temperature solution heat exchanger 405 and second throttle valve 406. The liquid phase outlet of low-pressure generator 403 is connected to the inlet of absorber 412 after passing through low-temperature solution heat exchanger 409 and third throttle valve 410. The gas phase outlet of low-pressure generator 403 is connected to the inlet of condenser 401. The outlet of cooling tower 414 is connected to the inlet of cooling tower 414 after passing through cooling water pump 413, absorber 412, and condenser 401. The chilled water return is supplied to the user after passing through chilled water regulating valve 417.

[0019] The thermal energy storage subsystem 5 includes a low-temperature thermal oil storage tank 501, an air mixer 502, a waste heat recovery heat exchanger 503, a thermal oil mixer 504, and a high-temperature thermal oil storage tank 505. The exhaust outlets of the first air heat exchanger 105 and the second air heat exchanger 305 are respectively connected to the inlet of the air mixer 502. The outlet of the air mixer 502 is connected to the hot-side inlet of the waste heat recovery heat exchanger 503. The thermal oil outlet of the heat exchanger 303 is connected to the thermal oil mixer 504, and the outlet of the thermal oil mixer 504 is connected to the high-temperature thermal oil storage tank 505. The outlet of the high-temperature thermal oil storage tank 505 is connected to the heat source inlet of the high-pressure generator 404 of the absorption refrigeration subsystem 4, and the heat source outlet of the high-pressure generator 404 is connected to the low-temperature thermal oil storage tank 501. The outlet of the low-temperature thermal oil storage tank 501 is connected to the thermal oil splitter 205 of the proton exchange membrane fuel cell subsystem 2. The thermal energy storage subsystem 5 is a dual-tank sensible heat storage structure, and the heat transfer oil is biphenyl-biphenyl ether, silicone oil or heat transfer oil products.

[0020] In operation, the solar-assisted chemical reforming subsystem 1 serves as the core of the fuel conversion system, comprising a concentrating photovoltaic thermal collector 101, a photovoltaic inverter unit 102, a fuel reforming reactor 103, an air oxidation reactor 104, and a first air heat exchanger 105. In this embodiment, methanol is used as the reference fuel. The concentrating photovoltaic thermal collector 101 converts solar energy into electrical energy (output via the photovoltaic inverter unit 102) and thermal energy; the generated heat preheats the methanol fuel and then enters the reactor. Inside the reactor, methanol undergoes a partial oxidation / reformation reaction with the oxygen carrier to generate hydrogen-rich syngas. The reduced oxygen carrier (e.g., Cu) after the reaction enters the air oxidation reactor 104, where it is oxidized by air preheated by the first air heat exchanger 105, releasing heat. The regenerated oxidized oxygen carrier (e.g., CuO) is recycled back to the fuel reforming reactor 103, achieving oxygen carrier recycling.

[0021] The proton exchange membrane fuel cell subsystem 2, serving as the core of power generation, includes a fuel cooler 201, a proton exchange membrane fuel cell stack 202, a DC / AC inverter unit 203, a cathode air preheater 204, and a heat transfer oil distributor 205. Hydrogen-rich fuel from the solar-assisted chemical loop reforming subsystem 1 is cooled by the fuel cooler 201 before entering the anode of the fuel cell stack 202 to generate electricity. The DC power generated by the fuel cell stack is connected to the grid via the inverter unit 203. Thermal management of the proton exchange membrane fuel cell subsystem 2 utilizes low-temperature heat transfer oil from the thermal energy storage subsystem 5 to pre-cool the fuel and cool the fuel cell stack, recovering waste heat generated by the electrochemical reaction.

[0022] The chemical looping combustion subsystem 3, serving as the system's "exhaust gas treatment and reheating center," includes a fuel reactor 301, an air reactor 302, a heat exchanger 303, an air mixer 304, and a second air heat exchanger 305. The unreacted exhaust gas (containing H2 and CO) from the anode of the proton exchange membrane fuel cell stack 202 enters the fuel reactor 301, where it undergoes a complete oxidation reaction with the oxygen carrier (such as CuO), releasing chemical energy. The high-temperature oxygen carrier after the reaction enters the air reactor (302) for regeneration. Crucially, the exhaust gas discharged from the fuel reactor (301) mainly consists of CO2 and H2O, naturally isolated from N2 in the air. High-purity CO2 can be obtained through condensation, achieving low-cost carbon capture. Simultaneously, the high-temperature heat generated by the reaction is transferred to the heat transfer oil through the heat exchanger 303, upgrading the medium-temperature heat transfer oil to a high-temperature heat transfer oil.

[0023] The absorption refrigeration subsystem 4 utilizes waste heat for cooling. Its core components include a high-pressure generator 404, a low-pressure generator 403, a condenser 401, an evaporator 416, an absorber 412, and various solution heat exchangers and pumps. The high-pressure generator 404 is directly driven by high-temperature heat transfer oil from the thermal energy storage subsystem 5 and employs a double-effect lithium bromide refrigeration cycle. It efficiently produces cooling capacity through a two-stage generation process for use in summer or transitional seasons.

[0024] The thermal energy storage subsystem 5, serving as the system's energy buffer and distribution hub, includes a low-temperature thermal oil storage tank 501, a high-temperature thermal oil storage tank 505, an air mixer 502, a waste heat recovery heat exchanger 503, and a thermal oil mixer 504. The thermal energy storage subsystem 5 establishes a closed-loop circulation of the thermal oil: the low-temperature oil starts from storage tank 501, absorbs waste heat from the battery stack, and its temperature rises. It is then further heated to a high temperature by the chemical looping combustion subsystem 3, stored in storage tank 505, and finally drives the absorption refrigeration subsystem 4 to perform work before cooling and returning to the source. Furthermore, the air mixer 502 collects exhaust gas from all air reactors and tail gas from heat exchanger 303, which together are used to produce domestic hot water through the waste heat recovery heat exchanger 503, effectively utilizing the last bit of heat in the system.

[0025] This system is modular and scalable, and is widely applicable to green building energy supply, distributed energy stations in zero-carbon industrial parks, and independent power and heating systems in isolated / remote areas.

[0026] This invention provides a distributed energy supply system integrating solar-assisted chemical loop reforming and a fuel cell, comprising solar-assisted chemical loop reforming 1, proton exchange membrane fuel power generation 2, chemical loop combustion 3, an absorption refrigeration subsystem 4, and a thermal energy storage subsystem 5. A concentrated photovoltaic (PV) solar thermal collector captures solar energy to preheat the fuel and generate electricity. The preheated fuel undergoes chemical loop reforming to produce hydrogen-rich reformed gas, which is then supplied to the fuel cell for efficient power generation. The fuel cell anode exhaust gas enters the fuel reactor of the chemical loop combustion subsystem, where lattice oxygen is provided by an oxygen carrier to achieve nitrogen-free dilution oxidation, generating product gas mainly composed of CO2 and H2O. The product gas is cooled, condensed, and dehydrated before being output with CO2 enrichment, and can optionally enter a buffer tank / compression unit. The system recovers waste heat from the fuel cell and high-temperature flue gas from chemical loop combustion through a closed-loop heat transfer oil system, storing the waste heat in high- and low-temperature heat transfer oil tanks to provide a stable heat source for absorption refrigeration. The control unit adjusts the distribution of heat transfer oil, the circulation of oxygen carrier, and the air / fuel flow rate based on solar irradiance, load demand, and the state of charge of thermal storage, so as to achieve the smoothing of solar energy fluctuations and flexible response to cold, heat, and electrical loads, while having both high energy efficiency and low carbon emissions.

[0027] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A distributed energy supply system integrating solar-assisted chemical reforming and fuel cells, characterized in that, It includes a solar-assisted chemical loop reforming subsystem (1), a proton exchange membrane fuel cell subsystem (2), a chemical loop combustion subsystem (3), an absorption refrigeration subsystem (4), and a thermal energy storage subsystem (5); The solar-assisted chemical loop reforming subsystem (1) includes a concentrating photovoltaic thermal collector (101), a photovoltaic inverter unit (102), a fuel reforming reactor (103), an air oxidation reactor (104), and a first air heat exchanger (105); the electrical output terminal of the concentrating photovoltaic thermal collector (101) is connected to the photovoltaic inverter unit (102), and its heat working fluid outlet is connected to the fuel inlet of the fuel reforming reactor (103); the fuel outlet of the fuel reforming reactor (103) is connected to the proton exchange membrane fuel cell subsystem (2); an oxygen carrier circulation pipeline is provided between the fuel reforming reactor (103) and the air oxidation reactor (104); external air enters the air oxidation reactor (104) after being preheated by the first air heat exchanger (105), and the exhaust outlet of the air oxidation reactor (104) is connected to the hot side inlet of the first air heat exchanger (105); The proton exchange membrane fuel cell subsystem (2) includes a fuel cooler (201), a proton exchange membrane fuel cell stack (202), a DC / AC inverter unit (203), a cathode air preheater (204), and a heat transfer oil distributor (205); the fuel is connected to the fuel outlet of the fuel reforming reactor (103) via the hot-side inlet of the fuel cooler (201), and the fuel is connected to the anode inlet of the proton exchange membrane fuel cell stack (202) via the hot-side outlet of the fuel cooler (201); the anode outlet of the proton exchange membrane fuel cell stack (202) is connected to the chemical looping combustion subsystem (3); the cathode air preheater (204) of the proton exchange membrane fuel cell stack (202) is connected to the anode outlet of the proton exchange membrane fuel cell stack (205). The exhaust outlet is connected to the hot-side inlet of the cathode air preheater (204). After being preheated by the cathode air preheater (204), the external air enters the cathode inlet of the proton exchange membrane fuel cell stack (202). The low-temperature heat transfer oil outlet of the thermal energy storage subsystem (5) is connected to the heat transfer oil splitter (205). The first outlet of the heat transfer oil splitter (205) is connected to the cold-side inlet of the fuel cooler (201), and the second outlet is connected to the cooling channel inlet of the proton exchange membrane fuel cell stack (202). The heat transfer oil outlet of the fuel cooler (201) and the heat transfer oil outlet of the proton exchange membrane fuel cell stack (202) merge and are then connected to the chemical looping combustion subsystem (3). The chemical loop combustion subsystem (3) includes a fuel reactor (301), an air reactor (302), a heat exchanger (303), an air mixer (304), and a second air heat exchanger (305). The fuel inlet of the fuel reactor (301) is connected to the anode outlet of the proton exchange membrane fuel cell stack (202). The anode exhaust gas from the proton exchange membrane fuel cell stack (202) enters the fuel reactor (301) and undergoes a reduction reaction with the internal oxygen carrier. The high-temperature exhaust outlet of the fuel reactor (301) is connected to the hot-side inlet of the heat exchanger (303), and the cold-side outlet of the fuel cooler (201) is connected to the heat exchanger (303). The cold side inlet of the fuel reactor (301) is heated by heat absorption and flows to the thermal energy storage subsystem (5); the first inlet of the air mixer (304) is connected to the exhaust outlet of the cathode air preheater (204) of the proton exchange membrane fuel cell subsystem (2), and the external air is preheated by the second air heat exchanger (305) and then connected to the second inlet of the air mixer (304); the outlet of the air mixer (304) is connected to the air inlet of the air reactor (302), and the exhaust outlet of the air reactor (302) is connected to the hot side inlet of the second air heat exchanger (305); an oxygen carrier circulation pipeline is provided between the fuel reactor (301) and the air reactor (302).

2. The distributed energy supply system integrating solar-assisted chemical loop reforming and fuel cells according to claim 1, characterized in that, The absorption refrigeration subsystem (4) includes: a condenser (401), a first throttle valve (402), a low-pressure generator (403), a high-pressure generator (404), a high-temperature solution heat exchanger (405), a second throttle valve (406), a first solution pump (407), a flow divider valve (408), a low-temperature solution heat exchanger (409), a third throttle valve (410), a second solution pump (411), an absorber (412), a cooling water pump (413), a cooling tower (414), a fourth throttle valve (415), an evaporator (416), and chilled water. The regulating valve (417); the heat source inlet of the high-pressure generator (404) is connected to the outlet of the high-temperature heat transfer oil storage tank (505) of the thermal energy storage subsystem (5); the heat source outlet of the high-pressure generator (404) is connected to the outlet of the low-temperature heat transfer oil storage tank (501) of the thermal energy storage subsystem (5); the gas phase outlet of the high-pressure generator (404) is connected to the inlet of the condenser (401) after passing through the low-pressure generator (403) and the first throttle valve (402); the gas phase outlet of the condenser (401) is connected to the inlet of the evaporator (416) after passing through the fourth throttle valve (415). The outlet of the evaporator (416) is connected to the inlet of the absorber (412). The outlet of the absorber (412) is connected to the inlet of the diversion valve (408) after passing through the second solution pump (411) and the low-temperature solution heat exchanger (409). After passing through the diversion valve (408), it is divided into two paths: one path is connected to the inlet of the low-pressure generator (403), and the other path is connected to the inlet of the high-pressure generator (404) after passing through the first solution pump (407) and the high-temperature solution heat exchanger (405). The liquid phase outlet of the high-pressure generator (404) is connected to the high-temperature solution heat exchanger (405). The second throttle valve (406) is connected to the inlet of the low-pressure generator (403); the liquid phase outlet of the low-pressure generator (403) is connected to the inlet of the absorber (412) via the low-temperature solution heat exchanger (409) and the third throttle valve (410); the gas phase outlet of the low-pressure generator (403) is connected to the inlet of the condenser (401); the outlet of the cooling tower (414) is connected to the inlet of the cooling tower (414) via the cooling water pump (413), the absorber (412), and the condenser (401); the chilled water return is supplied to the user via the chilled water regulating valve (417).

3. The distributed energy supply system integrating solar-assisted chemical reforming and fuel cells according to claim 1, characterized in that, The thermal energy storage subsystem (5) includes a low-temperature thermal oil storage tank (501), an air mixer (502), a waste heat recovery heat exchanger (503), a thermal oil mixer (504), and a high-temperature thermal oil storage tank (505); the exhaust outlet of the first air heat exchanger (105) and the exhaust outlet of the second air heat exchanger (305) are respectively connected to the inlet of the air mixer (502); the outlet of the air mixer (502) is connected to the hot side inlet of the waste heat recovery heat exchanger (503); the heat exchanger (303) The outlet of the heat transfer oil is connected to the heat transfer oil mixer (504), and the outlet of the heat transfer oil mixer (504) is connected to the high-temperature heat transfer oil storage tank (505); the outlet of the high-temperature heat transfer oil storage tank (505) is connected to the heat source inlet of the high-pressure generator (404) of the absorption refrigeration subsystem (4), and the heat source outlet of the high-pressure generator (404) is connected to the low-temperature heat transfer oil storage tank (501); the outlet of the low-temperature heat transfer oil storage tank (501) is connected to the heat transfer oil splitter (205) of the proton exchange membrane fuel cell subsystem (2).

4. The distributed energy supply system integrating solar-assisted chemical loop reforming and fuel cells according to claim 1, characterized in that, The fuel reforming reactor (103) uses methanol, ethanol or natural gas as carbon-containing fuel, and the oxygen carrier is one of CuO / Cu, Fe2O3 / Fe3O4 or NiO / Ni system or a composite system thereof.

5. The distributed energy supply system integrating solar-assisted chemical loop reforming and fuel cells according to claim 1, characterized in that, The thermal energy storage subsystem (5) is a dual-tank sensible heat storage structure, and the heat transfer oil is biphenyl-biphenyl ether, silicone oil or heat transfer oil product.

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