A cold-heat-power optimization scheduling method for an agricultural park integrated energy system based on biomass-solar coupling

Abstract

A method for optimizing the cooling, heating, and power (CHP) scheduling of an integrated energy system for agricultural parks based on biomass-solar coupling includes the following steps: constructing an integrated energy system for agricultural parks based on biomass-solar coupling; constructing a flexible load model for agricultural parks based on their load characteristics; constructing an optimized CHP scheduling model for the integrated energy system for agricultural parks based on biomass-solar coupling, and introducing a tiered carbon trading mechanism to limit carbon emissions. This invention provides a method for optimizing the CHP scheduling of an integrated energy system for agricultural parks based on biomass-solar coupling, which can solve the problems of insufficient energy supply, high carbon emissions, and high costs in some integrated energy systems for agricultural parks.

Description

Technical Field

[0001] This invention relates to the field of integrated energy system optimization scheduling, and in particular to a method for optimizing the scheduling of cooling, heating and power in an integrated energy system for agricultural parks based on biomass-solar coupling. Background Technology

[0002] Socioeconomic development has led to a surge in energy demand and a decline in fossil fuel reserves. The consumption of fossil fuels has caused environmental problems, with massive carbon emissions exacerbating the greenhouse effect and contributing to global warming. Increasing the use of non-fossil energy and reducing carbon emissions are critical issues that urgently need to be addressed.

[0003] IES (Environmentally Integrated Systems) integrates multiple energy sources for joint supply, meeting the demands of multi-energy loads at the end-user level and serving as a crucial support for promoting the utilization of non-fossil energy and reducing carbon emissions. Currently, most literature focuses on the low-carbon economic operation of IES, such as Reference 1: "Optimization of Thermal Power in Integrated Energy Systems Considering Tiered Carbon Trading Mechanism and Electric Hydrogen Production [J]. Electric Power Automation Equipment, 2021, 41(09): 48-55." and Reference 2: "Multi-Time-Scale Optimization Scheduling of Integrated Energy Systems Including Electricity-to-Gas Conversion and Carbon Capture Coupling [J]. China Electric Power, 1-13." While the low-carbon economic scheduling models established in these references can effectively reduce carbon emissions and improve economic efficiency, the specific applicable scenarios for IES are somewhat vague. Therefore, References 3: "Research on Low-Carbon Economic Scheduling Methods of Integrated Energy Systems in Agricultural Parks [D]. Hebei Agricultural University, 2023." and Reference 4: "Research on Optimization Scheduling Methods of Integrated Energy Systems in Facility Agricultural Industrial Parks [D]. Lanzhou University of Technology, 2021." emphasize the low-carbon economic operation of IES in agricultural parks and utilize biomass energy. However, the established AIES model structure is relatively simple, neglecting the absorption of wind and solar energy and the mutual conversion between various energy sources, which prevents AIES performance from being further improved.

[0004] Demand response is a way for users to participate in system scheduling. By guiding users to adjust their energy demand through energy market prices and incentive response mechanisms, it can effectively reduce load fluctuations and achieve economical system operation. References 5: "Optimal Scheduling of Integrated Energy Systems Considering Tiered Carbon Trading Mechanism [J]. China Electric Power, 1-12." and 6: "Low-Carbon Optimization Operation of Integrated Energy Systems in Industrial Parks Considering CCPP-P2G-CHP Synergy [J / OL]. Journal of North China Electric Power University (Natural Science Edition), 1-12.", although the above references have established relatively complete demand response models, it is still necessary to analyze the load type specifically for different IES loads and select an appropriate demand response mechanism according to the load type.

[0005] Biomass is a renewable organic matter produced by green plants through photosynthesis, and can be categorized into multiple sectors including agriculture, forestry, aquaculture, and waste management. Biomass energy has a shorter carbon emission cycle than fossil fuels, allowing emitted CO2 to complete its carbon cycle naturally, resulting in near-zero net CO2 emissions; therefore, biomass is called a carbon-neutral fuel. Biomass resources are characterized by their widespread availability, short regeneration cycle, low pollution, and high energy potential. Utilizing biomass through advanced energy processing methods can help solve the IES (Environmentally, Environmentally, and Biomass) energy supply problems in agricultural parks or remote rural areas, improve agricultural production and lifestyles, and promote the construction of modern agricultural parks.

[0006] Agricultural parks can generate a large amount of biomass, and how to utilize it efficiently is of great significance to the development of agricultural parks. References 7: "Research on the Integration of Biomass with Solar and Geothermal Energy in Building CCHP System [D]. Hunan University, 2018." and 8: "Optimization of Biomass Energy Integrated Energy System Considering Tiered Carbon-Green Certificate Joint Trading and Demand Response [J]. Electric Power Science and Engineering, 2024, 40(07):10-25." These references studied the utilization scenarios of biomass energy in IES, but did not consider the source of biomass. Reference 9: "Planning Method of Integrated Energy System for Agricultural Industrial Park Considering Biomass Energy and Flexible Agricultural Load [J]. Power Grid Technology, 2024, 48(05):1836-1845." This paper uses a pyrolysis gasifier to produce biomass gas and biochar, and establishes an AIES that considers biomass energy and flexible agricultural load through high-level anaerobic fermentation of manure to produce biogas. However, the system structure is relatively simple and the absorption capacity is poor. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a method for optimizing the scheduling of cooling, heating and power in an integrated energy system for agricultural parks based on biomass-solar coupling, which can solve the problems of insufficient energy supply, high carbon emissions and high costs in some integrated energy systems for agricultural parks.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0009] A method for optimizing the scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling includes the following steps:

[0010] Step 1: Construct an integrated energy system for agricultural parks based on biomass-solar energy coupling;

[0011] Step 2: Based on the load characteristics of the agricultural park, construct a flexible load model for the agricultural park;

[0012] Step 3: Construct an optimized scheduling model for the integrated energy system of agricultural parks based on biomass-solar coupling, including cooling, heating, and power, and introduce a tiered carbon trading mechanism model to limit carbon emissions.

[0013] Step 1 involves constructing an integrated energy system for the agricultural park based on biomass-solar coupling, specifically including:

[0014] (1) Construct a biomass-solar energy coupling device model;

[0015] (2) Construct a coupled device model of P2G and CCS for electro-gas conversion;

[0016] (3) Construct a model of the energy conversion device;

[0017] (4) Construct an energy storage device model.

[0018] (1) Constructing a biomass-solar energy coupling device model, specifically including:

[0019] 1) Constructing a biomass gasification model

[0020] After being heated in a preheater, biomass enters the gasification tank. Its gas production rate is related to temperature. The biomass gas production rate and biomass output model are as follows:

[0021]

[0022] In the formula: η b,t and T t T represents the biomass gasification rate and temperature at time t, respectively; T0 is the optimal temperature for the biomass gasification tank, typically taken as 35℃; P BSC,b,t and m bio,t , respectively, represent the biomass input power and biomass mass flow rate at time t; LHV is the lower heating value of biomass;

[0023] 2) Construct a biomass gasification pond model

[0024] The energy to maintain a suitable temperature in the biomass gasification tank is provided by a combination of solar collectors and heat exchangers; the heat balance formula and heat dissipation model within the biomass gasification tank are as follows:

[0025]

[0026] In the formula: ρ and C p V represents the density and specific heat capacity of biomass materials. d The volume of the gasification tank is T; HRT is the time the material spends in the gasification tank; T amb,t U represents the ambient temperature at time t. h and S d P represents the total heat transfer coefficient and total heat dissipation area of ​​the gasification pool. GT,h,t and P GT,loss,t These represent the energy required by the gasification pool at time t and the heat dissipation, respectively.

[0027] 3) Construct a solar collector model

[0028] The solar collector prioritizes supplying heat to the biomass gasification pond, and any excess heat energy can be directly supplied to the heat load. The solar collector model is as follows:

[0029] P TC,t =n TC η TC,t G TC,t Q TC (3);

[0030] In the formula: P TC,t η TC,t and G TC,t Let n be the output power, conversion efficiency, and solar radiation intensity of the solar collector at time t; TC Q represents the number of solar collectors. TC The area of ​​a single solar collector;

[0031] 4) Construct a biomass-solar coupled BSC system model

[0032] Part of the biomass gas is used to generate electricity through combustion in an internal combustion engine, and part is used to generate heat through a heat exchanger. The generated heat energy is used partly to meet the heat load, partly to supply the biomass gasification cell, and partly to supply the absorption chiller for refrigeration. The biomass-solar coupled BSC system model is as follows:

[0033]

[0034] In the formula: P BSC,e,t P BSC,h,t and P BSC,c,t Let P represent the electrical power, thermal power, and cooling power output by the BSC at time t; BSC,b,t P is the total power input to the BSC at time t; HRB,h,t P is the heat energy supplied to the chiller at time t; HRB,tc,t To supply heat energy to the gasification pool; P TC,h,t The heat energy supplied to the solar collector at time t is the heat load; η BSC,e η BSC,h and η BSC,c These represent the electrical, thermal, and cooling efficiencies of the BSC output, respectively; P GT,h,t Let be the energy required by the biomass gasification cell at time t;

[0035] The operational constraints and ramping constraints of the BSC system are as follows:

[0036]

[0037] In the formula: and These are the upper and lower limits of the input power of the BSC system, respectively. and The upper and lower limits of ramp power for BSC system; and The upper and lower limits of the input absorption chiller power; and The upper and lower limits of the ramp power of the input absorption chiller; and These are the upper and lower limits of the heat energy supplied to the gasification pool, respectively. and These represent the upper and lower limits of the ramp power for the gasification tank.

[0038] (2) Constructing a coupled device model of P2G and CCS for electro-gas conversion, specifically including:

[0039] The coupled power-to-gas (P2G) and carbon capture system (CCS) can absorb excess wind and solar energy and reduce CO2 emissions. The coupling model of P2G and CCS is as follows:

[0040] 1) Electrolytic cell EL

[0041]

[0042] In the formula: P EL,e,t Let t be the electrical energy input to EL; Let η be the hydrogen energy input to EL at time t; EL The energy conversion efficiency of EL; These are the upper and lower limits of the input EL power, respectively; These are the upper and lower limits of EL ramp power, respectively.

[0043] 2) Methane reactor MR

[0044]

[0045] In the formula: P represents the hydrogen energy input to MR at time t. MR,g,t η is the gas power output of MR at time t; MR The energy conversion efficiency of MR; These are the upper and lower limits of the hydrogen power input to MR, respectively; These are the upper and lower limits of MR ramp power, respectively;

[0046] 3) Hydrogen fuel cells (HFC)

[0047]

[0048] In the formula: P represents the hydrogen power input to the HFC at time t. HFC,e,t η is the output electrical power of the HFC at time t; HFC The efficiency of HFC energy conversion; These are the upper and lower limits of the input HFC hydrogen power, respectively; These are the upper and lower limits of HFC ramp power, respectively;

[0049] 4) Carbon Capture System (CCS)

[0050] Considering the coupling failure issue between P2G and CCS due to insufficient wind and solar energy output, a CO2 storage tank is introduced into the carbon capture CCS to strengthen the coupling between P2G and CCS. CO2 mainly comes from gas-fired boilers and BSC systems. The CCS model is as follows:

[0051]

[0052] In the formula: P CCS,t P CCS,f,t and P CCS,o,t These represent the total energy consumption, fixed energy consumption, and operating energy consumption of the CCS at time t; ε represents the mass of CO2 captured by the CCS at time t; CCS The energy consumption coefficient of CCS; and The CO2 masses produced by GB and BSC at time t are respectively; ω CCS The efficiency of CO2 capture by CCS; and The amount of CO2 supplied by CCS and the amount of CO2 sealed for MR at time t are respectively the amount of CO2 required by MR at time t.

[0053] The operating power constraints and ramp power constraints for CCS are as follows:

[0054]

[0055] In the formula: These are the upper and lower limits of CCS energy consumption, respectively. These represent the upper and lower limits of CCS ramp energy consumption, respectively.

[0056] (3) Constructing an energy conversion device model specifically includes:

[0057] Energy conversion equipment includes an electric boiler (EB), an electric chiller (ERU), and a gas boiler (GB); the electric boiler (EB) converts electrical energy into heat energy, the electric chiller (ERU) converts electrical energy into cold energy, and the gas boiler (GB) burns natural gas to generate heat energy; the models are as follows:

[0058] 1) Electric Boiler EB

[0059]

[0060] In the formula: P EB,e,t P represents the electrical power consumed by EB at time t. EB,h,tη is the thermal power generated by EB at time t; EB The heating efficiency of EB; These are the upper and lower limits of the power consumption of EB, respectively. These are the upper and lower limits of EB's ramp power;

[0061] 2) Electric Refrigeration Unit (ERU)

[0062]

[0063] In the formula: P ERU,e,t P represents the electrical energy consumed by the ERU at time t. ERU,c,t η represents the cold energy generated by ERU at time t; ERU For ERU cooling efficiency; The upper and lower limits of the input ERU electrical power; These are the upper and lower limits of ERU ramp power, respectively.

[0064] 3) Gas-fired boilers GB

[0065]

[0066] In the formula: P GB,g,t P GB,h,t η represents the input gas power and output thermal power of GB at time t, respectively; GB GB energy conversion efficiency; GB input power upper and lower limits; These are the upper and lower limits of the ramp power for GB.

[0067] (4) Constructing an energy storage device model, specifically including:

[0068] Multi-element energy storage includes electrical energy storage, thermal energy storage, cold energy storage, and hydrogen energy storage. A general model is as follows:

[0069] 1) Charge / discharge power and state constraints:

[0070]

[0071] In the formula: x represents the type of energy storage device, represented by e, h, c, and H2 for electrical, thermal, cold, and hydrogen energy storage, respectively; P x,cha,t P x,dis,t Let I represent the charging and discharging power of energy storage device x at time t; x,cha,t I x,dis,t Let represent the charging and discharging states of energy storage device x at time t; and These represent the upper and lower limits of the charging power of energy storage device x, respectively. and These represent the upper and lower limits of the energy release power of the energy storage device x, respectively.

[0072] 2) Energy storage state continuity constraints:

[0073]

[0074] In the formula: S x,t Let δ be the storage capacity of energy storage device x at time t; x η is the self-loss coefficient of energy storage device x; x,cha η x,dis are the charging and discharging efficiencies of energy storage device x, respectively; The upper and lower limits of energy storage capacity; S x,1 S represents the storage capacity of energy storage device x at time 1; x,24 Let x be the storage capacity of the energy storage device at 24 hours.

[0075] Step 2 involves constructing a flexible load model for the agricultural park, specifically including:

[0076] (1) Construct a flexible load model for agricultural parks;

[0077] 1) The electrical load of a greenhouse includes electric irrigation machines, ventilators, rolling shutters, plant grow lights, and crop dryers. The greenhouse electrical load model is as follows:

[0078]

[0079] In the formula: P gh,e,t P represents the power consumption of the greenhouse at time t. pump,t P fan,t P driver,t P light,t and P ldryer,t These are the rated power of a single electric irrigation machine, ventilator, roller shutter machine, plant grow light, and crop dryer, respectively; d pump,t d fan,t d driver,t d light,t and d dryer,t These are 0-1 variables, corresponding to the working status of electric irrigation machines, ventilators, roller shutter machines, plant grow lights, and crop dryers; N1 is the number of electric irrigation machines; N2 is the number of ventilators; N3 is the number of roller shutter machines; N4 is the number of plant grow lights; and N5 is the number of crop dryers.

[0080] 2) The greenhouse heat load model is as follows:

[0081]

[0082] In the formula: T gh,t Let T be the temperature of the greenhouse at time t; gh,t+1 P represents the greenhouse temperature at time t+1. gh,su,t P gh,in,t and Pgh,loss,t These represent the heat supply, heat production, and heat dissipation of the greenhouse at time t; ρ air c air and ν gh These represent the air density, specific heat capacity, and greenhouse volume of the greenhouse, respectively. The greenhouse heat loss P... gh,loss,t This includes heat loss from walls, floors, and airflow;

[0083] 3) The electrical load of a livestock farm includes the ventilation system, feed feeding system, and waste treatment system. The heating model for the livestock farm is as follows:

[0084]

[0085] In the formula: P farm,e,t P represents the power consumption of the aquaculture farm at time t. t air P t feed and P t waste These represent the power consumption of the ventilation system, feed feeding system, and waste treatment system at time t, respectively; β t air β t feed and β t waste These are 0-1 variables, representing whether the ventilation system, feed feeding system, and waste treatment system are in operation at time t, respectively; M1 is the number of ventilation systems; M2 is the number of feed feeding systems; and M3 is the number of waste treatment systems.

[0086] The feed feeding system integrates a feed crusher, a feed mixer, and an automatic feeder. The electrical load model of the feed feeding system is as follows:

[0087]

[0088] In the formula: P t feed Let t be the output of the feeding system. and These are the rated power of the feed crusher, feed mixer, and automatic feeder, respectively; α cut α mix and α rel These are 0-1 variables, representing the operating status of each device; η i mix and The working efficiency of each piece of equipment in the feed feeding system;

[0089] The waste treatment system includes wastewater treatment equipment and waste shredding equipment. The electrical load model of the waste treatment system is as follows:

[0090] P t waste =P t sewage +P t duc (20);

[0091] In the formula: g and eP t duc These represent the power used to process sewage and park waste at time t, respectively. The power consumption of the waste treatment system;

[0092] (2) Conduct flexible load characteristics analysis of agricultural parks;

[0093] 1) Loads that can be moved

[0094] The power consumption time of the shiftable load is continuous. The shiftable load model is as follows:

[0095]

[0096] In the formula: and L shift The loads before and after the translation are respectively; S shift A set of starting time periods; They are respectively at t before translation S t S+1 t D Load at any moment; P τ shift , These are the translations at τ, τ+1, and τ+t, respectively. D Load at time -1; [t sh- ,t sh+ ] represents the translational interval; t s The starting time period; t D For a duration of time;

[0097] Compensation for the park's expenses after relocation F shift for:

[0098]

[0099] In the formula: Price compensation for unit load shifting; For L shift The sum of translational loads; t sh- t is the starting time of the load shift; sh+ -t D +1 represents the starting time after the load shift;

[0100] 2) The transferable load model is as follows:

[0101]

[0102] In the formula: These represent the upper and lower limits of transferable load, respectively; β t It is a 0-1 variable, indicating whether the transition occurs at time t; P t tran The loads at time t before and after the transfer are respectively; [t] tr- ,t tr+ [ ] represents the transition interval;

[0103] Compensation for park fees F after relocation tran for:

[0104]

[0105] In the formula: The compensation price for load transfer;

[0106] 3) The load reduction model is as follows:

[0107]

[0108] In the formula: P t cut* P t cut These represent the load at time t before and after the reduction; γ t It is a 0-1 variable, indicating whether it is reduced at time t; N represents the maximum continuous reduction time. max This represents the maximum number of cuts.

[0109] The cost of the park needs to be compensated after the reduction. cut for:

[0110]

[0111] In the formula: The compensation price for load reduction.

[0112] Step three involves establishing an optimized scheduling model for the integrated energy system (cooling, heating, and power) of the agricultural park based on biomass-solar coupling, specifically including:

[0113] Step 3.1: Construct the objective function

[0114] Energy purchase cost C based on the AIES integrated energy system of agricultural parks buy Cost of curtailing wind and solar power (C) cut Carbon trading costs Operation and maintenance cost Com and park compensation costs C fill , construct with total cost C total The minimum low-carbon economy targets are as follows:

[0115]

[0116] 1) Energy purchase cost

[0117]

[0118] In the formula: α e and α g These are the unit prices for electricity and gas purchases, respectively; P e,buy,t P g,buy,t These represent the electricity and gas purchased at time t, respectively; T is the time period.

[0119] 2) Costs of curtailing wind and solar power

[0120]

[0121] Where: δ wt δ pv These are the wind curtailment and solar curtailment penalty factors, respectively; P wt,cut,t P pv,cut,t These represent the power of wind and solar power curtailed at time t, respectively.

[0122] 3) Carbon trading costs

[0123] A tiered carbon trading mechanism model is constructed, as follows:

[0124]

[0125] In the formula: E IES E e,buy E BSC and E GB These are the total AIES quota, external power purchase quota, BSC system quota, and GB quota, respectively; χ e , χ g and χ b These are the carbon emission allowance coefficients per unit of electricity, natural gas, and biomass gas consumption, respectively; E IES,a E e,buy,a P BSC,b,a and P GB,h,a These are the actual carbon emissions from IES, upstream power purchase, BSC system, and GB, respectively; E MR,a E represents the actual amount of CO2 absorbed by the MR. IES,t represents the carbon emissions trading amount; H is the coefficient corresponding to different carbon emission ranges.

[0126] 4) Operation and maintenance costs

[0127]

[0128] Where: β j P represents the unit operation and maintenance cost of the j-th type of equipment; j,t Let be the output power of the j-th device at time t; j is the type of device.

[0129] 5) Park compensation costs

[0130] C fill =F shift +F tran +F cut (32);

[0131] Step 3.2, Constraints

[0132] The constraints include wind and solar power output constraints, energy purchase constraints, power balance constraints, equipment energy constraints, and energy storage constraints; specifically as follows:

[0133] 1) Wind and solar power output constraints

[0134]

[0135] In the formula: and These are the upper limits of output for photovoltaic units and wind turbine units, respectively.

[0136] P pv,t P represents the photovoltaic power at time t. wt,t Let t be the power of the wind turbine;

[0137] 2) Constraints on electricity and gas purchases

[0138]

[0139] In the formula: and These are the upper and lower limits for the amount of electricity that can be purchased; and These represent the upper and lower limits of gas purchase capacity, respectively; P e,buy,t P represents the power purchased from the upstream power grid at time t. g,buy,t The gas purchase power from the superior gas network at time t;

[0140] 3) Power balance constraints

[0141]

[0142] In the formula: and These represent the electrical loads that can be shifted, transferred, and reduced at time t, respectively.

[0143] 4) Thermal power balance constraint

[0144]

[0145] In the formula: P farm,h,t The heating power of the aquaculture farm at time t; and These represent the heat load that can be shifted and reduced at time t, respectively.

[0146] 5) Cold power balance constraint

[0147] P BSC,c,t +P ERU,c,t +P c,dis,t =P load,c,t +P c,cha,t (37);

[0148] 6) Natural gas power balance constraints

[0149] P g,buy,t +P MR,g,t =P GB,g,t (38);

[0150] 7) Hydrogen power balance constraint

[0151]

[0152] This invention provides a method for optimizing the scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar energy coupling, which has the following technical advantages:

[0153] 1) Due to insufficient electricity, heat, and cooling energy supply in some agricultural parks' integrated energy systems, carbon emissions and operating costs remain high, and wind and solar power curtailment is severe. This significantly hinders the development of planting and animal husbandry in agricultural parks and greatly impacts the stability of their integrated energy systems. Therefore, step 1 of this invention combines biomass waste generated in agricultural parks with solar collectors to construct a biomass-solar coupled system. It also introduces a power-to-gas (P2G) device and a carbon capture system (CCS). The P2G device produces hydrogen through water electrolysis, effectively absorbing new energy sources such as wind and solar power. The CCS captures carbon dioxide, which is then fed into a methane reactor to produce methane, effectively reducing carbon emissions in agricultural parks. Finally, an integrated energy system for agricultural parks considering biomass-solar coupling is constructed. This system not only effectively alleviates the energy supply shortage problem in agricultural parks' integrated energy systems but also significantly improves the low-carbon economic benefits of agricultural parks.

[0154] 2) Because the load in agricultural parks is an adjustable load, it is not being utilized. To address this, step 2 of this invention analyzes the electrical and thermal loads of greenhouses and livestock farms in agricultural parks to establish a flexible load model for agricultural parks. This model allows the load in agricultural parks to participate in grid regulation, effectively alleviating the peak-valley difference in the power grid and improving the low-carbon economic benefits of the comprehensive energy system in agricultural parks.

[0155] 3) To seek a low-carbon economic operation scheme for the integrated energy system of agricultural parks. To this end, step 3 of this invention establishes an optimized scheduling model for the cooling, heating, and power of the integrated energy system of agricultural parks that considers biomass-solar coupling, and introduces a tiered carbon trading mechanism to further limit the carbon emissions of agricultural parks. This model can effectively seek the optimal operation scheme for the integrated energy system of agricultural parks.

[0156] 4) Regarding the shortcomings mentioned in the background technology: the AIES model structure of the agricultural park integrated energy system is relatively simple, ignoring the absorption of wind and solar energy and the mutual conversion between multiple energy sources, which leads to the failure to further improve the performance of AIES;

[0157] This invention introduces an electricity-to-gas (P2G) device, a carbon capture system (CCS) device, an electric boiler (EB) device, an electric chiller (ERU) device, and a gas-fired boiler (GB) device into an integrated energy system for agricultural parks. The P2G device produces hydrogen through water electrolysis, effectively utilizing renewable energy sources such as wind and solar power. The CCS device captures carbon dioxide and feeds it into a methane reactor to produce methane, effectively reducing carbon emissions in agricultural parks. The EB device converts electrical energy into heat, the ERU converts electrical energy into cooling energy, and the gas-fired boiler converts natural gas into heat, achieving mutual energy conversion and improving the low-carbon economic benefits of agricultural parks.

[0158] 5) Regarding the shortcomings mentioned in the background technology: Although the above literature has established a relatively complete demand response model, it is still necessary to analyze the load type specifically for different IES loads and select an appropriate demand response mechanism according to the load type.

[0159] This invention takes into account the different load characteristics of agricultural parks compared to conventional loads, making conventional price-based and substitution-based demand responses less applicable. Therefore, this invention conducts an in-depth analysis of the electrical and thermal loads of greenhouses and livestock farms in agricultural parks, establishing a flexible load model for agricultural parks. Without affecting the normal operation of agricultural park production, the agricultural park load participates in grid regulation, reducing the peak-to-valley difference in the grid and effectively lowering the operating costs of the agricultural park's integrated energy system.

[0160] 6) Regarding the shortcomings mentioned in the background: The above literature studied the utilization scenarios of biomass energy in IES, but did not consider the source of biomass.

[0161] This invention combines waste biomass generated in agricultural parks with solar collectors to construct a biomass-solar coupled system, which can effectively reuse waste and reduce system operating costs.

[0162] 7) Regarding the shortcomings mentioned in the background technology: An AIES considering biomass energy and agricultural flexible loads has been established, but the system structure is relatively simple and the absorption capacity is poor.

[0163] This invention introduces an electricity-to-gas (P2G) device, a carbon capture system (CCS) device, an electric boiler (EB) device, an electric chiller (ERU) device, a gas boiler (GB) device, and an electric thermal energy storage device into an integrated energy system for agricultural parks. The P2G device produces hydrogen through water electrolysis, effectively utilizing new energy sources such as wind and solar power. The CCS device captures carbon dioxide and feeds it into a methane reactor to produce methane, effectively reducing carbon emissions in agricultural parks. The EB device converts electrical energy into heat, the ERU converts electrical energy into cold energy, and the gas boiler converts natural gas into heat, achieving mutual energy conversion. The electric thermal energy storage device effectively realizes energy time-shifting, which is beneficial to improving the low-carbon economic benefits of agricultural parks. Attached Figure Description

[0164] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0165] Figure 1 This is a diagram of the AIES framework for BSC.

[0166] Figure 2 This is a diagram of the BSC system.

[0167] Figure 3 The diagram shows the power output of wind and solar power, as well as the electricity, heat, and cooling loads.

[0168] Figure 4 To optimize the distribution map of flexible electrical load in the agricultural park.

[0169] Figure 5 To optimize the flexible heat load distribution map of the agricultural park.

[0170] Figure 6 To optimize the distribution map of flexible electrical load in the agricultural park.

[0171] Figure 7 To optimize the flexible heat load distribution map of the agricultural park.

[0172] Figure 8 A comparison chart of flexible electrical loads in the agricultural park before and after optimization.

[0173] Figure 9 A comparison diagram of the flexible heat load of the agricultural park before and after optimization.

[0174] Figure 10 This is the power balance diagram for scenario 1.

[0175] Figure 11 This is the thermal power balance diagram for scenario 1.

[0176] Figure 12 This is the cooling power balance diagram for scenario 1. Detailed Implementation

[0177] A method for optimizing the scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling includes the following steps:

[0178] Step 1: Construct an integrated energy system for agricultural parks based on biomass-solar coupling, introducing electricity-to-gas and carbon capture coupling equipment, multi-energy conversion equipment and energy storage equipment, and establishing models for each equipment.

[0179] (1) Biomass-solar coupled device model

[0180] 1) Biomass gasification model

[0181] Biomass is heated in a preheater before entering the gasification tank. Its gas production rate is related to temperature. The biomass gas production rate and biomass output model are as follows:

[0182]

[0183] In the formula: η b,t and T t Tt represents the biomass gasification rate and temperature of the biomass gasification cell at time t; T0 is the optimal temperature of the biomass gasification cell, typically taken as 35℃; Pt BSC,b,t and m bio,t , respectively, represent the input power and biomass mass flow rate at time t; LHV is the lower heating value of biomass.

[0184] 2) Biomass gasification pond model

[0185] The gasification efficiency of a biomass gasification tank is closely related to both the tank's internal temperature and the ambient temperature. This invention considers using a combination of solar collectors and heat exchangers to provide the energy needed to maintain a suitable temperature within the biomass gasification tank. The heat balance formula and heat dissipation model within the biomass gasification tank are as follows:

[0186]

[0187] In the formula: ρ and C p V represents the density and specific heat capacity of biomass materials. d The volume of the biomass gasification tank is T; HRT is the time the material spends in the biomass gasification tank; T amb,t U represents the ambient temperature at time t. h and S dP represents the total heat transfer coefficient and total heat dissipation area of ​​the biomass gasification tank. GT,h,t and P GT,loss,t These represent the energy required and heat dissipation of the biomass gasification pool at time t, respectively.

[0188] 3) Solar collectors

[0189] The solar collector's output is highest at midday, but the outside temperature is high at this time, and the biomass gasification cell requires less energy, resulting in wasted heat energy. Therefore, this invention considers that the solar collector prioritizes supplying heat to the biomass gasification cell, and the excess heat energy can be directly supplied to the heat load. The solar collector model is as follows:

[0190] P TC,t =n TC η TC,t G TC,t Q TC (3);

[0191] In the formula: P TC,t η TC,t and G TC,t Let n be the output power, conversion efficiency, and solar radiation intensity of the solar collector at time t; TC Q represents the number of solar collectors. TC This refers to the area of ​​a single solar collector.

[0192] 4) Biomass-Solar Coupled BSC System Model

[0193] Part of the biomass gas is used to generate electricity through internal combustion engines, and another part is used to generate heat through heat exchangers. The generated heat energy is used partly to meet the heat load, partly to supply the gasification pond, and partly to supply the absorption chiller for refrigeration. The BSC system model is as follows:

[0194]

[0195] In the formula: P BSC,e,t P BSC,h,t and P BSC,c,t Let P represent the electrical power, thermal power, and cooling power output by the BSC at time t; BSC,b,t P is the total power input to the BSC at time t; HRB,h,t P is the heat energy supplied to the chiller at time t; HRB,tc,t To supply heat energy to the gasification pool; P TC,h,t The heat energy supplied to the solar collector at time t is the heat load; η BSC,e η BSC,h and η BSC,c These represent the electrical efficiency, thermal efficiency, and cooling efficiency output by the BSC, respectively; P GT,h,t Let t be the energy required for the biomass gasification cell at time t.

[0196] The operational constraints and ramping constraints of the BSC system are as follows:

[0197]

[0198] In the formula: and These are the upper and lower limits of the input power of the BSC system, respectively. and The upper and lower limits of ramp power for BSC system; and The upper and lower limits of the input absorption chiller power; and The upper and lower limits of the ramp power of the input absorption chiller; and These are the upper and lower limits of the heat energy supplied to the gasification pool, respectively. and These represent the upper and lower limits of the ramp power for the gasification tank.

[0199] (2) Model of a coupled electro-gas (P2G) and carbon capture system (CCS)

[0200] P2G coupled with CCS can absorb excess wind and solar energy and reduce CO2 emissions. The P2G and CCS coupling model is as follows:

[0201] 1) Electrolytic cell EL

[0202]

[0203] In the formula: P EL,e,t Let t be the electrical energy input to EL; η is the hydrogen energy input to EL at time t; EL The energy conversion efficiency of EL; These are the upper and lower limits of the input EL power, respectively; These are the upper and lower limits of EL ramp power, respectively.

[0204] 2) Methane reactor MR

[0205]

[0206] In the formula: P represents the hydrogen energy input to MR at time t. MR,g,t η is the gas power output of MR at time t; MR The energy conversion efficiency of MR; These are the upper and lower limits of the hydrogen power input to MR, respectively; These are the upper and lower limits of MR ramp power, respectively.

[0207] 3) Hydrogen fuel cell (HFC)

[0208]

[0209] In the formula: P represents the hydrogen power input to the HFC at time t. HFC,e,t η is the electrical power output by the HFC at time t; HFC The efficiency of energy conversion in HFC; These are the upper and lower limits of the input HFC hydrogen power, respectively; These represent the upper and lower limits of HFC ramp power, respectively.

[0210] 4) Carbon capture system (CCS)

[0211] Considering the coupling failure issue between P2G and CCS due to insufficient wind and solar energy output, a CO2 storage tank is introduced into the CCS to strengthen the coupling between P2G and CCS. CO2 mainly comes from gas-fired boilers and BSC systems. The CCS model is as follows:

[0212]

[0213] In the formula: P CCS,t P CCS,f,t and P CCS,o,t These represent the total energy consumption, fixed energy consumption, and operating energy consumption of the CCS at time t; ε represents the mass of CO2 captured by the CCS at time t; CCS The energy consumption coefficient of CCS; and The CO2 produced by GB and BSC at time t are respectively; ω CCS The efficiency of CO2 capture by CCS; and The amounts of CO2 supplied by CCS and the amount of CO2 sealed are respectively the amount required by MR at time t.

[0214] The operating power constraints and ramp power constraints of CCS are as follows:

[0215]

[0216] In the formula: These are the upper and lower limits of CCS energy consumption, respectively. These represent the upper and lower limits of CCS ramp energy consumption, respectively.

[0217] (3) Energy conversion equipment model

[0218] Energy conversion devices mainly include EB, ERU, and GB. EB is used to convert electrical energy into heat energy, ERU converts electrical energy into cold energy, and GB burns natural gas to generate heat energy. Their models are as follows:

[0219] 1) Electric boiler EB

[0220]

[0221] In the formula: P EB,e,t P represents the electrical power consumed by EB at time t. EB,h,t η is the thermal power generated by EB at time t; EB The heating efficiency of EB; These are the upper and lower limits of the electrical power consumed by EB, respectively; These are the upper and lower limits of EB's ramp power.

[0222] 2) Electric Refrigeration Unit (ERU)

[0223]

[0224] In the formula: P ERU,e,t P represents the electrical energy consumed by the ERU at time t. ERU,c,t η represents the cold energy generated by ERU at time t; ERU For ERU cooling efficiency; The upper and lower limits of the input ERU electrical power; These are the upper and lower limits of ERU ramp power, respectively.

[0225] 3) Gas-fired boilers GB

[0226]

[0227] In the formula: P GB,g,t P GB,h,t η represents the input gas power and output thermal power of GB at time t, respectively; GB GB energy conversion efficiency; These are the upper and lower limits of the GB input power; These are the upper and lower limits of the ramp power for GB.

[0228] (4) Energy storage device model

[0229] Multi-element energy storage mainly consists of electrical energy storage, thermal energy storage, cold energy storage, and hydrogen energy storage. Its general model is as follows:

[0230] 1) Charge / discharge power and state constraints:

[0231]

[0232] In the formula: x represents the type of energy storage device, represented by e, h, c, and H2 for electrical, thermal, cold, and hydrogen energy storage, respectively; P x,cha,t P x,dis,t Let I represent the charging and discharging power of energy storage device x at time t, respectively; x,cha,t I x,dis,t Let represent the charging and discharging states of energy storage device x at time t, respectively; and These represent the upper and lower limits of the charging power of energy storage device x, respectively. and These represent the upper and lower limits of the energy release power of the energy storage device x, respectively.

[0233] 2) Energy storage state continuity constraints:

[0234]

[0235] In the formula: S x,t Let δ be the storage capacity of energy storage device x at time t; x η is the self-loss coefficient of energy storage device x; x,cha η x,dis are the charging and discharging efficiencies of energy storage device x, respectively; The upper and lower limits of energy storage capacity; S x,1 S represents the storage capacity of energy storage device x at time 1; x,24 Let x be the storage capacity of the energy storage device at 24 hours.

[0236] Step 2: Based on the load characteristics of the agricultural park, establish a flexible load model for the agricultural park.

[0237] Considering that the load characteristics of agricultural parks differ from those of conventional loads, this invention analyzes in detail the load characteristics of greenhouses and livestock farms to further consider the impact of agricultural park loads on AIES. The specific model is established as follows:

[0238] (1) Load model of agricultural park

[0239] 1) Greenhouse electrical load

[0240] The electrical load of a greenhouse mainly includes electric irrigation machines, ventilators, rolling shutters, plant grow lights, and crop dryers, as shown in the model below:

[0241]

[0242] In the formula: P gh,e,t P represents the power consumption of the greenhouse at time t. pump,t P fan,t P driver,t P light,t and P ldryer,t These are the rated power of a single electric irrigation machine, ventilator, roller shutter machine, plant grow light, and crop dryer, respectively; d pump,t d fan,t d driver,t d light,t and d dryer,tThe variables are 0-1, corresponding to the working status of electric irrigation machines, ventilators, roller shutter machines, plant grow lights, and crop dryers; N1 is the number of electric irrigation machines; N2 is the number of ventilators; N3 is the number of roller shutter machines; N4 is the number of plant grow lights; and N5 is the number of crop dryers.

[0243] 2) Heat load of greenhouse

[0244]

[0245] In the formula: T gh,t Let T be the temperature of the greenhouse at time t; gh,t+1 P represents the greenhouse temperature at time t+1. gh,su,t P gh,in,t and P gh,loss,t These represent the heat supply, heat production, and heat dissipation of the greenhouse at time t; ρ air c air and ν gh These represent the air density, specific heat capacity, and greenhouse volume of the greenhouse, respectively. The greenhouse heat loss P... gh,loss,t This includes heat loss from walls, floors, and airflow.

[0246] 3) Electricity load of the aquaculture farm

[0247] The heating model for a livestock farm is similar to that of a greenhouse. The electrical load of a livestock farm mainly consists of the ventilation system, feed feeding system, and waste treatment system. The heating model for a livestock farm is as follows:

[0248]

[0249] In the formula: P farm,e,t P represents the power consumption of the aquaculture farm at time t. t air P t feed and P t waste These represent the power consumption of the ventilation system, feed feeding system, and waste treatment system at time t, respectively; β t air β t feed and β t waste The variables are 0-1, representing whether the ventilation system, feed feeding system, and waste treatment system are in operation at time t, respectively; M1 is the number of ventilation systems; M2 is the number of feed feeding systems; and M3 is the number of waste treatment systems.

[0250] The feed feeding system is a farm feeding system integrating a feed crusher, a feed mixer, and an automatic feeder. The electrical load model of the feed feeding system is as follows:

[0251]

[0252] In the formula: P t feed Let t be the output of the feeding system. and These are the rated power of the feed crusher, feed mixer, and automatic feeder, respectively; α cut α mix and α rel These are 0-1 variables, representing the working status of the feed crusher, feed mixer, and automatic feeder; η i mix and These represent the working efficiency of the feed crusher, feed mixer, and automatic feeder, respectively.

[0253] The waste treatment system mainly consists of wastewater treatment equipment and waste shredding equipment. The electrical load model of the waste treatment system is as follows:

[0254]

[0255] In the formula: g and eP t duc Let be the power used to process sewage and park waste at time t, respectively. The power consumption of the waste treatment system;

[0256] (2) Analysis of Flexible Load Characteristics in Agricultural Parks

[0257] Based on the load characteristics of agricultural parks, the electrical load can be categorized into reduceable load, shiftable load, and transferable load. Considering users' sensitivity to heat load, only reduceable and shiftable heat loads are considered for greenhouses. Additionally, load adjustment compensation can be provided to the parks to enhance their incentives.

[0258] 1) Loads that can be moved

[0259] In this invention, the shiftable load model, the transferable load model, and the load reduction model are all combinations of electrical load and thermal load, and are general models. For example, a shiftable load refers to a combination of shiftable electrical load and shiftable thermal load.

[0260] The simulation in this invention takes into account the translation, transfer and reduction of electrical load; the thermal load only takes into account the translation and reduction, and the transfer of thermal load is not considered because agricultural parks are sensitive to thermal load.

[0261] The movable loads in agricultural parks mainly include movable electrical loads and movable thermal loads. Movable loads have continuous energy consumption and must be moved in one continuous section, such as electric irrigation machines and automatic feeders. The model is as follows:

[0262]

[0263] In the formula: and L shift The loads before and after the translation are respectively; S shift This is the set of times at which the load can be transferred. They are respectively at t before translation S t S+1 t D The workload of the moment; These are the translations at τ, τ+1, and τ+t, respectively. D Load at time -1; [t sh- ,t sh+ ] represents the translational interval; t s The starting time period; t D For a duration of time.

[0264] Compensation for the park's expenses after relocation F shift for:

[0265]

[0266] In the formula: Price compensation for unit load shifting; For L shift The sum of translational loads; t sh- t is the starting time of the load shift; sh+ -t D +1 represents the starting time after the load shift.

[0267] 2) Transferable load

[0268] Transferable electrical loads are relatively flexible and do not require continuous power, but the total load must remain unchanged before and after the transfer, such as roller blinds and plant grow lights. The model is as follows:

[0269]

[0270] In the formula: These represent the upper and lower limits of transferable load, respectively; β t P is a 0-1 variable, representing whether a transition occurs at time t; t tran* P t tran The loads at time t before and after the transfer are respectively; [t] tr- ,t tr+ ] represents the transition interval.

[0271] Compensation for park fees F after relocation tran for:

[0272]

[0273] In the formula: The compensation price for load transfer.

[0274] 3) Load can be reduced

[0275] Reduceable loads refer to the reduction of a portion of the load without affecting the normal operation of the park, such as crop dryers and feed crushers. The model is as follows:

[0276]

[0277] In the formula: P t cut* P t cut These represent the load at time t before and after the reduction; γ t It is a 0-1 variable, indicating whether it is reduced at time t; N represents the maximum continuous reduction time. max This represents the maximum number of reductions.

[0278] The cost of the park needs to be compensated after the reduction. cut for:

[0279]

[0280] In the formula: The compensation price for load reduction.

[0281] Step 3: Establish an optimized scheduling model for the integrated energy system of agricultural parks based on biomass-solar coupling, including cooling, heating, and power, and introduce a tiered carbon trading mechanism to limit carbon emissions.

[0282] (1) Objective function

[0283] This invention comprehensively considers the energy purchase cost C of the Agricultural Integrated Energy System (AIES) for agricultural parks. buy Cost of curtailing wind and solar power (C) cut Carbon trading costs Operation and maintenance cost C om and park compensation costs C fill , construct with total cost C total The minimum low-carbon economy targets are as follows:

[0284]

[0285] 1) Energy purchase cost

[0286] Energy purchase costs mainly consist of electricity and gas purchase costs, as shown in the model below:

[0287]

[0288] In the formula: α e and α g These are the unit prices for electricity and gas, respectively; P e,buy,t P g,buy,t t represents the power purchased for electricity and gas at time t, respectively; T is the time period.

[0289] 2) Costs of curtailing wind and solar power

[0290]

[0291] Where: δ wt δ pv These are the wind curtailment and solar curtailment penalty factors, respectively; P wt,cut,t P pv,cut,t These represent the power of wind and solar power curtailment at time t, respectively.

[0292] 3) Carbon trading costs

[0293] This invention establishes a tiered carbon trading mechanism model, as follows:

[0294]

[0295] In the formula: E IES E e,buy E BSC and E GB These are the total AIES quota, external power purchase quota, BSC system quota, and GB quota, respectively; χ e , χ g and χ b These are the carbon emission allowance coefficients for units of electricity, natural gas, and biomass gas consumption, respectively. IES,a E e,buy,a P BSC,b,a and P GB,h,a These are the actual carbon emissions from IES, upstream power purchase, BSC system, and GB, respectively; E MR,a E represents the actual amount of CO2 absorbed by the MR. IES,t denoted as carbon emissions trading amount; H represents the coefficient corresponding to different carbon emission ranges.

[0296] 4) Operation and maintenance costs

[0297]

[0298] Where: β j P represents the unit operation and maintenance cost of the j-th type of equipment; j,t Let be the output power of the j-th device at time t; j represents the type of device.

[0299] 5) Park compensation costs

[0300] C fill =F shift +F tran +F cut (32);

[0301] (2) Constraints

[0302] The model constraints in this invention mainly include wind and solar power output constraints, energy purchase constraints, power balance constraints, equipment energy constraints, and energy storage constraints. Specifically:

[0303] 1) Wind and solar power output constraints

[0304]

[0305] In the formula: and These are the upper limits of output for photovoltaic units and wind turbine units, respectively, P pv,t Let P be the photovoltaic power at time t; wt,t Fan power at time t;

[0306] 2) Constraints on electricity and gas purchases

[0307]

[0308] In the formula: and These are the upper and lower limits for the amount of electricity that can be purchased; and These are the upper and lower limits of gas purchase capacity, respectively, P e,buy,t Let P be the power purchased from the upstream power grid at time t. g,buy,t The gas purchase power from the superior gas network at time t;

[0309] 3) Power balance constraints

[0310]

[0311] In the formula: and These represent the electrical load that can be shifted, the electrical load that can be transferred, and the electrical load that can be reduced at time t, respectively.

[0312] 4) Thermal power balance constraint

[0313]

[0314] In the formula: P farm,h,t The heating power of the aquaculture farm at time t; and These represent the heat load that can be shifted and the heat load that can be reduced at time t, respectively.

[0315] 5) Cold power balance constraint

[0316] PBSC,c,t +P ERU,c,t +P c,dis,t =P load,c,t +P c,cha,t (37);

[0317] 6) Natural gas power balance constraints

[0318] P g,buy,t +P MR,g,t =P GB,g,t (38);

[0319] 7) Hydrogen power balance constraint

[0320]

[0321] This invention selects an agricultural park in Gansu, China as an example for calculation analysis, performing optimized scheduling on a 24-hour cycle with a 1-hour time interval. BSC coupling equipment parameters are shown in Table 1; biomass gasification pool parameters are shown in Table 2; flexible load parameters of the agricultural park are shown in Table 3; wind power, photovoltaic power output, and electricity, heat, and cooling load data are shown below. Figure 3 This example uses the CPLEX solver for optimized solution.

[0322] Table 1 BSC Coupling Device Parameters

[0323]

[0324] Table 2 Parameters of Biomass Gasification Tank

[0325]

[0326] Table 3 Classification of Equipment Characteristics in Agricultural Parks

[0327]

[0328]

[0329] To verify the rationality of considering the flexible load of agricultural parks and the CCS-P2G coupling model in this invention, and the superiority of the BSC coupling system compared with the cogeneration system using natural gas as feedstock, the scheduling results of the following four scenarios are compared and analyzed:

[0330] Scenario 1: Considering the participation of the BSC system in AIES, flexible load in agricultural parks, and coupling of CCS and P2G;

[0331] Scenario 2: Considering the participation of the BSC system in AIES, the coupling of CCS and P2G, and not considering the flexible load of agricultural parks;

[0332] Scenario 3: Considering the participation of the BSC coupled system in AIES, flexible load in agricultural parks, without considering P2G and CCS;

[0333] Scenario 4: Considering the participation of traditional combined cooling, heating and power systems in AIES, flexible loads in agricultural parks, and coupling of CCS and P2G.

[0334] (1) Economic and carbon emission analysis

[0335] The optimization scheduling results for each scenario are shown in Table 3.

[0336] As shown in Table 3, compared with Scenario 1, the energy purchase cost of Scenario 2 increased by RMB 342.3, an increase of 245.9%; the carbon trading cost increased by RMB 76, an increase of 5.5%; and the carbon emissions increased by 189 kg; the total cost increased by RMB 148.2. This is because Scenario 1 optimized the flexible load of the agricultural park by reducing, shifting, and transferring some of the load. While ensuring the normal operation of all parts of the agricultural park, it reduced some of the load and reduced the peak-valley difference of the load, which is conducive to the stable economic operation of AIES.

[0337] As shown in Table 3, compared to Scenario 1, Scenario 3 has an increased carbon trading cost of 40.8 yuan and an increased carbon emission of 131.9 kg. This is because Scenario 1 introduces P2G and CCS equipment in AIES, which can absorb excess wind and solar energy and reduce CO2 emissions.

[0338] As shown in Table 3, compared with Scenario 1, Scenario 4 has an increased gas purchase cost of 80.5 yuan, an increased carbon trading cost of 240.8 yuan, an increased carbon emission of 678 kg, and a total cost increase of 369.3 yuan, representing an increase of 16.9%. This is because, compared with the traditional combined cooling, heating and power system in Scenario 4 which uses natural gas as raw material, the BSC system in Scenario 1 uses biomass as the main energy source, which can make full use of waste, reduce energy consumption and CO2 emissions, and reduce system costs.

[0339] (2) Flexible load analysis of agricultural parks

[0340] Comparing scenario 1 and scenario 2, we analyze the impact of optimizing the flexible electrical and thermal loads of the agricultural park on the results.

[0341] Depend on Figure 6 and Figure 8 It can be seen that after optimization, the amount of electricity load that can be reduced during the period (12:00-20:00) is reduced. The load that can be shifted 1 and the load that can be shifted 2 are shifted from the peak load period (12:00 and 20:00) to the off-peak period (5:00-8:00), respectively. The load that can be transferred is shifted from the peak load period (1:00-4:00) to the off-peak period (4:00-8:00), which helps to alleviate the peak-valley difference of the electricity load.

[0342] Depend on Figure 7 and Figure 9 It can be seen that the heat load that can be reduced decreases during the period (11:00-13:00), while the heat load that can be transferred is shifted from the peak load period (18:00-20:00) to the period (11:00-13:00), which effectively alleviates the difference between peak and valley heat loads and improves the economic efficiency of the system.

[0343] Depend on Figure 10 , Figure 11 and Figure 12 It can be seen that when the AIES solar power output is insufficient, the BSC system, as a supplementary energy source, can not only effectively alleviate the system's energy shortage, but also make full use of waste and reduce the system's operating costs.

[0344] (3) Comprehensive evaluation considering BSC system access to AIES

[0345] To analyze in detail the differences between the BSC system in Scenario 1 and the traditional combined cooling, heating, and power (CCHP) system in Scenario 4, this invention introduces primary energy saving rate (PESR), CO2 emission saving rate (CEER), and total cost saving rate (TCSR) as system evaluation indicators from economic, energy, and environmental perspectives. Detailed model reference: "Research on Two-Stage Robust Capacity Configuration of Biomass Gas-Solar-Wind Integrated Energy System [D]. Shandong University, 2022." Where P... PEC1 P PEC4 E CDE1 E CDE4 C COST1 C COST4 These represent the total primary energy consumption (PEC), CO2 emissions (CDE), and total cost per day for scenarios 1 and 4, respectively.

[0346] Table 5 Evaluation Indicators

[0347]

[0348]

[0349] As shown in Table 5, although the primary energy consumption of Scenario 1 is 16.2% greater than that of Scenario 4, its CO2 emissions are reduced by 13.3% and the total cost is reduced by 14.5%. By utilizing biomass waste, the system operating cost and CO2 emissions can be effectively reduced. Therefore, the BSC system has better characteristics than the traditional cogeneration system participating in AIES.

Claims

1. A method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, characterized in that, Includes the following steps: Step 1: Construct an integrated energy system for agricultural parks based on biomass-solar energy coupling; Step 2: Based on the load characteristics of the agricultural park, construct a flexible load model for the agricultural park; Step 3: Construct an optimized scheduling model for the integrated energy system of agricultural parks based on biomass-solar coupling, including cooling, heating, and power, and introduce a tiered carbon trading mechanism model to limit carbon emissions; Step 1 involves constructing an integrated energy system for the agricultural park based on biomass-solar coupling, specifically including: (1) Construct a biomass-solar energy coupling device model; (2) Construct a coupled device model of P2G and CCS for electro-gas conversion; (3) Construct a model of the energy conversion device; (4) Construct an energy storage device model; (1) Constructing a biomass-solar energy coupling device model, specifically including: 1) Construct a biomass gasification model; 2) Construct a biomass gasification pond model; 3) Construct a solar collector model; 4) Construct a biomass-solar coupled BSC system model. Part of the biomass gas is used to generate electricity through internal combustion engine combustion, and part of it is used to generate heat through heat exchanger. Part of the generated heat energy meets the heat load, part is supplied to the biomass gasification pool, and the other part is supplied to the absorption chiller for refrigeration. Step 3 involves establishing an optimized scheduling model for the integrated energy system (cooling, heating, and power) of the agricultural park based on biomass-solar coupling, specifically including: Step 3.1: Construct the objective function Energy purchase cost C based on the AIES integrated energy system of agricultural parks buy Cost of curtailing wind and solar power (C) cut Carbon trading costs Operation and maintenance cost C om and park compensation costs C fill , construct with total cost C total The minimum low-carbon economy targets are as follows: 1) Energy purchase cost In the formula: α e and α g These are the unit prices for electricity and gas purchases, respectively; P e,buy,t P g,buy,t These represent the electricity and gas purchased at time t, respectively; T is the time period. 2) Costs of curtailing wind and solar power Where: δ wt δ pv These are the wind curtailment and solar curtailment penalty factors, respectively; P wt,cut,t P pv,cut,t These represent the power of wind and solar power curtailed at time t, respectively. 3) Carbon trading costs A tiered carbon trading mechanism model is constructed, as follows: In the formula: E IES E e,buy E BSC and E GB These are the total AIES quota, external power purchase quota, BSC system quota, and GB quota, respectively; χ e , χ g and χ b These are the carbon emission allowance coefficients per unit of electricity, natural gas, and biomass gas consumption, respectively; E IES,a E e,buy,a P BSC,b,a and P GB,h,a These are the actual carbon emissions from IES, upstream power purchase, BSC system, and GB, respectively; E MR,a E represents the actual amount of CO2 absorbed by the MR. IES,t H represents the carbon emissions trading amount; H is the coefficient corresponding to different carbon emission ranges; P BSC,b,t P is the total power input to the BSC at time t; GB,h,t P represents the output thermal power of GB at time t; e,buy,t The power purchased from the upper-level power grid at time t; 4) Operation and maintenance costs Where: β j P represents the unit operation and maintenance cost of the j-th type of equipment; j,t Let be the output power of the j-th device at time t; j is the type of device. 5) Park compensation costs C fill =F shift +F tran +F cut (32); In the formula: F shift To compensate the park for the costs incurred after the relocation; F tran To compensate the park for the costs incurred after the relocation; F cut The cost of reducing the park's operations needs to be compensated. Step 3.2, Constraints The constraints include wind and solar power output constraints, energy purchase constraints, power balance constraints, equipment energy constraints, and energy storage constraints; specifically as follows: 1) Wind and solar power output constraints In the formula: and These are the upper limits of output for photovoltaic units and wind turbine units, respectively. P pv,t P represents the photovoltaic power at time t. wt,t Let t be the power of the wind turbine; 2) Constraints on electricity and gas purchases In the formula: and These are the upper and lower limits for the amount of electricity that can be purchased; and These represent the upper and lower limits of gas purchase capacity, respectively; P e,buy,t P represents the power purchased from the upstream power grid at time t. g,buy,t The gas purchase power from the superior gas network at time t; 3) Power balance constraints In the formula: and These represent the electrical loads that can be shifted, transferred, and reduced at time t, respectively. P e,buy,t P represents the power purchased from the upstream power grid at time t. wt,t P is the power of the wind turbine at time t; pv,t P represents the photovoltaic power at time t. BSC,e,t P represents the electrical power output by the BSC at time t. HFC,e,t P is the output power of the HFC at time t. e,dis,t P is the discharge power of the stored energy at time t. EL,e,t P is the electrical energy input to EL at time t; CCS,t P represents the total energy consumption of the CCS at time t. ERU,e,t P represents the electrical energy consumed by the ERU at time t. EB,e,t P represents the electrical power consumed by EB at time t. e,cha,t The charging power of the electrical energy storage at time t; P gh,e,t P represents the power consumption of the greenhouse at time t. farm,e,t Let t be the power consumption of the aquaculture farm at time t; 4) Thermal power balance constraint In the formula: P GB,h,t P represents the output thermal power of GB at time t; BSC,h,t P represents the thermal power output by the BSC at time t. TC,h,t P represents the thermal energy supplied by the solar collector to the total heat load at time t. EB,h,t P represents the thermal power generated by the electric heating device at time t. h,dis,t P represents the heat release power at time t of thermal energy storage. h,cha,t P is the power of thermal energy storage at time t. gh,su,t P represents the heat supplied to the greenhouse at time t. farm,h,t The heating power of the aquaculture farm at time t; and These represent the heat load that can be shifted and reduced at time t, respectively. 5) Cold power balance constraint P BSC,c,t +P ERU,c,t +P c,dis,t =P load,c,t +P c,cha,t (37); In the formula: P BSC,c,t P represents the cooling power output of the BSC at time t. ERU,c,t P represents the cooling power generated by the ERU at time t. c,dis,t P represents the power released during cold energy storage at time t. load,c,t P is the cooling power required at time t; c,cha,t The power required for cold energy storage at time t; 6) Natural gas power balance constraints P g,buy,t +P MR,g,t =P GB,g,t (38); In the formula: P g,buy,t P is the power of purchasing gas from the upstream gas network at time t; MR,g,t P represents the power of the natural gas generated by the methane generator at time t. GB,g,t Let t be the power consumption of the gas-fired boiler using natural gas. 7) Hydrogen power balance constraint In the formula: The hydrogen gas produced by the electrolyzer at time t; The hydrogen release capacity of the hydrogen storage tank at all times; Let t be the hydrogen power consumed by the hydrogen fuel cell; The hydrogen power consumed by the methane generator at any given time; The hydrogen filling power of the hydrogen storage tank at all times.

2. The method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, as described in claim 1, is characterized in that: (1) Constructing a biomass-solar energy coupling device model, specifically including: Biomass is heated in a preheater before entering the gasification tank. Its gas production rate is related to temperature. The biomass gas production rate and biomass output model are as follows: In the formula: η b,t and T t T represents the biomass gasification rate and temperature at time t, respectively; T0 is the optimal temperature for the biomass gasification tank, typically taken as 35℃; P BSC,b,t and m bio,t , respectively, represent the biomass input power and biomass mass flow rate at time t; LHV is the lower heating value of biomass; The energy to maintain a suitable temperature in the biomass gasification tank is provided by a combination of solar collectors and heat exchangers; the heat balance formula and heat dissipation model within the biomass gasification tank are as follows: In the formula: ρ and C p V represents the density and specific heat capacity of biomass materials. d The volume of the gasification tank is T; HRT is the time the material spends in the gasification tank; T amb,t U represents the ambient temperature at time t. h and S d P represents the total heat transfer coefficient and total heat dissipation area of ​​the gasification pool. GT,h,t and P GT,loss,t These represent the energy required by the gasification pool at time t and the heat dissipation, respectively. The solar collector prioritizes supplying heat to the biomass gasification pond, and any excess heat energy can be directly supplied to the heat load. The solar collector model is as follows: P TC,t =n TC or TC,t G TC,t Q TC (3); In the formula: P TC,t η TC,t and G TC,t Let n be the output power, conversion efficiency, and solar radiation intensity of the solar collector at time t; TC Q represents the number of solar collectors. TC The area of ​​a single solar collector; The biomass-solar coupled BSC system model is as follows: In the formula: P BSC,e,t P BSC,h,t and P BSC,c,t Let P represent the electrical power, thermal power, and cooling power output by the BSC at time t; BSC,b,t P is the total power input to the BSC at time t; HRB,h,t P is the heat energy supplied to the chiller at time t; HRB,tc,t To supply heat energy to the gasification pool; P TC,h,t The heat energy supplied to the solar collector at time t is the heat load; η BSC,e η BSC,h and η BSC,c These represent the electrical, thermal, and cooling efficiencies of the BSC output, respectively; P GT,h,t Let be the energy required by the biomass gasification cell at time t; The operational constraints and ramping constraints of the BSC system are as follows: In the formula: and These are the upper and lower limits of the input power of the BSC system, respectively. and The upper and lower limits of ramp power for BSC system; and The upper and lower limits of the input absorption chiller power; and The upper and lower limits of the ramp power of the input absorption chiller; and These are the upper and lower limits of the heat energy supplied to the gasification pool, respectively. and These represent the upper and lower limits of the ramp power for the gasification tank.

3. The method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, as described in claim 1, is characterized in that: (2) Constructing a coupled device model of P2G and CCS for electro-gas conversion, specifically including: The coupled power-to-gas (P2G) and carbon capture system (CCS) can absorb excess wind and solar energy and reduce CO2 emissions. The coupling model of P2G and CCS is as follows: 1) Electrolytic cell EL In the formula: P EL,e,t Let t be the electrical energy input to EL; Let η be the hydrogen energy input to EL at time t; EL The energy conversion efficiency of EL; These are the upper and lower limits of the input EL power, respectively; These are the upper and lower limits of EL ramp power, respectively. 2) Methane reactor MR In the formula: P represents the hydrogen energy input to MR at time t. MR,g,t η is the gas power output of MR at time t; MR The energy conversion efficiency of MR; These are the upper and lower limits of the hydrogen power input to MR, respectively; These are the upper and lower limits of MR ramp power, respectively; 3) Hydrogen fuel cells (HFC) In the formula: P represents the hydrogen power input to the HFC at time t. HFC,e,t η is the output electrical power of the HFC at time t; HFC The efficiency of HFC energy conversion; These are the upper and lower limits of the input HFC hydrogen power, respectively; These are the upper and lower limits of HFC ramp power, respectively; 4) Carbon Capture System (CCS) Considering the coupling failure issue between P2G and CCS due to insufficient wind and solar energy output, a CO2 storage tank is introduced into the carbon capture CCS to strengthen the coupling between P2G and CCS. CO2 mainly comes from gas-fired boilers and BSC systems. The CCS model is as follows: In the formula: P CCS,t P CCS,f,t and P CCS,o,t These represent the total energy consumption, fixed energy consumption, and operating energy consumption of the CCS at time t; ε represents the mass of CO2 captured by the CCS at time t; CCS The energy consumption coefficient of CCS; and The CO2 masses produced by GB and BSC at time t are respectively; ω CCS The efficiency of CO2 capture by CCS; and The amount of CO2 supplied by CCS and the amount of CO2 sealed for MR at time t are respectively the amount of CO2 required by MR at time t. The operating power constraints and ramp power constraints for CCS are as follows: In the formula: These are the upper and lower limits of CCS energy consumption, respectively. These represent the upper and lower limits of CCS ramp energy consumption, respectively.

4. The method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, as described in claim 1, is characterized in that: (3) Constructing an energy conversion device model specifically includes: Energy conversion equipment includes an electric boiler (EB), an electric chiller (ERU), and a gas boiler (GB); the electric boiler (EB) converts electrical energy into heat energy, the electric chiller (ERU) converts electrical energy into cold energy, and the gas boiler (GB) burns natural gas to generate heat energy; the models are as follows: 1) Electric Boiler EB In the formula: P EB,e,t P represents the electrical power consumed by EB at time t. EB,h,t η is the thermal power generated by EB at time t; EB The heating efficiency of EB; These are the upper and lower limits of the power consumption of EB, respectively. These are the upper and lower limits of EB's ramp power; 2) Electric Refrigeration Unit (ERU) In the formula: P ERU,e,t P represents the electrical energy consumed by the ERU at time t. ERU,c,t η represents the cold energy generated by ERU at time t; ERU For ERU cooling efficiency; The upper and lower limits of the input ERU electrical power; These are the upper and lower limits of ERU ramp power, respectively. 3) Gas-fired boilers GB In the formula: P GB,g,t P GB,h,t η represents the input gas power and output thermal power of GB at time t, respectively; GB GB energy conversion efficiency; GB input power upper and lower limits; These are the upper and lower limits of the ramp power for GB.

5. The method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, as described in claim 1, is characterized in that: (4) Constructing an energy storage device model, specifically including: Multi-element energy storage includes electrical energy storage, thermal energy storage, cold energy storage, and hydrogen energy storage. A general model is as follows: 1) Charge / discharge power and state constraints: In the formula: x represents the type of energy storage device, represented by e, h, c, and H2 for electrical, thermal, cold, and hydrogen energy storage, respectively; P x,cha,t P x,dis,t Let I represent the charging and discharging power of energy storage device x at time t; x,cha,t I x,dis,t Let represent the charging and discharging states of energy storage device x at time t; and These represent the upper and lower limits of the charging power of energy storage device x, respectively. and These represent the upper and lower limits of the energy release power of the energy storage device x, respectively. 2) Energy storage state continuity constraints: In the formula: S x,t Let δ be the storage capacity of energy storage device x at time t; x η is the self-loss coefficient of energy storage device x; x,cha η x,dis are the charging and discharging efficiencies of energy storage device x, respectively; The upper and lower limits of energy storage capacity; S x,1 S represents the storage capacity of energy storage device x at time 1; x,24 Let x be the storage capacity of the energy storage device at 24 hours.

6. The method for optimized scheduling of cooling, heating, and power in an integrated energy system for agricultural parks based on biomass-solar coupling, as described in claim 1, is characterized in that: Step 2 involves constructing a flexible load model for the agricultural park, specifically including: (1) Construct a flexible load model for agricultural parks; 1) The electrical load of a greenhouse includes electric irrigation machines, ventilators, rolling shutters, plant grow lights, and crop dryers. The greenhouse electrical load model is as follows: In the formula: P gh,e,t P represents the power consumption of the greenhouse at time t. pump,t P fan,t P driver,t P light,t and P ldryer,t These are the rated power of a single electric irrigation machine, ventilator, roller shutter machine, plant grow light, and crop dryer, respectively; d pump,t d fan,t d driver,t d light,t and d dryer,t These are 0-1 variables, corresponding to the working status of electric irrigation machines, ventilators, roller shutter machines, plant grow lights, and crop dryers; N1 is the number of electric irrigation machines; N2 is the number of ventilators; N3 is the number of roller shutter machines; N4 is the number of plant grow lights; and N5 is the number of crop dryers. 2) The greenhouse heat load model is as follows: In the formula: T gh,t Let T be the temperature of the greenhouse at time t; gh,t+1 P represents the greenhouse temperature at time t+1. gh,su,t P gh,in,t and P gh,loss,t These represent the heat supply, heat production, and heat dissipation of the greenhouse at time t; ρ air c air and ν gh These represent the air density, specific heat capacity, and greenhouse volume of the greenhouse, respectively; and the greenhouse heat loss P. gh,loss,t This includes heat loss from walls, floors, and airflow; 3) The electrical load of a livestock farm includes the ventilation system, feed feeding system, and waste treatment system. The heating model for the livestock farm is as follows: In the formula: P farm,e,t P represents the power consumption of the aquaculture farm at time t. t air P t feed and P t waste These represent the power consumption of the ventilation system, feed feeding system, and waste treatment system at time t, respectively. and These are 0-1 variables, representing whether the ventilation system, feed feeding system, and waste treatment system are in operation at time t, respectively; M1 is the number of ventilation systems; M2 is the number of feed feeding systems; and M3 is the number of waste treatment systems. The feed feeding system integrates a feed crusher, a feed mixer, and an automatic feeder. The electrical load model of the feed feeding system is as follows: In the formula: P t feed Let t be the output of the feeding system. and These are the rated power of the feed crusher, feed mixer, and automatic feeder, respectively; α cut α mix and α rel These are 0-1 variables, representing the operating status of each device; and The working efficiency of each piece of equipment in the feed feeding system; The waste treatment system includes wastewater treatment equipment and waste shredding equipment. The electrical load model of the waste treatment system is as follows: P t waste =P t sewage +P t duc (20); In the formula: P t sewa and P t duc These represent the power used to process sewage and park waste at time t, respectively. The power consumption of the waste treatment system; (2) Conduct flexible load characteristics analysis of agricultural parks; 1) Loads that can be moved The power consumption time of the shiftable load is continuous. The shiftable load model is as follows: In the formula: and L shift The loads before and after the translation are respectively; S shift A set of starting time periods; They are respectively at t before translation S t S+1 t D The workload of the moment; These are the translations at τ, τ+1, and τ+t, respectively. D Load at time -1; [t sh- ,t sh+ ] represents the translational interval; t s The starting time period; t D For a duration of time; Compensation for the park's expenses after relocation F shift for: In the formula: Price compensation for unit load shifting; For L shift The sum of translational loads; t sh- t is the starting time of load translation; sh+ -t D +1 represents the starting time after the load shift; 2) The transferable load model is as follows: In the formula: These represent the upper and lower limits of transferable load, respectively; β t P is a 0-1 variable, representing whether a transition occurs at time t; t tran* P t tran The loads at time t before and after the transfer are respectively; [t] tr- ,t tr+ [ ] represents the transition interval; Compensation for park fees F after relocation tran for: In the formula: The compensation price for load transfer; 3) The load reduction model is as follows: In the formula: P t cut* P t cut These represent the load at time t before and after the reduction; γ t It is a 0-1 variable, indicating whether it is reduced at time t; N represents the maximum continuous reduction time. max This represents the maximum number of cuts. The cost of the park needs to be compensated after the reduction. cut for: In the formula: The compensation price for load reduction.

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