Research On Multi-energy Coordinated Operation And Energy Management Strategy For Agricultural Greenhouse Integrated Energy Systems

Agricultural electricity consumption is an important part of the total electricity load in China.The growth of crops needs light,electricity,carbon,heat and other forms of energy.However,the inadequate coordination,extensive energy management,and low energy efficiency of the existing agricultural energy system seriously restrict the intensive and electrical development of modern agriculture.Therefore,researches on the multi-energy collaborative scheduling and energy management strategies of agricultural integrated energy systems,have a certain significance to achieve the carbon peaking and carbon neutrality goals.The research work is as follows:Firstly,the maximum production point tracking method for hybrid energy supply system in agricultural greenhouse is proposed.The state space equation of the agricultural solarboosted biogas energy generation system is formed.Based on the thermodynamic model of biogas fermentation,the effect of solar-heated biogas digester on fermentation biogas production rate is analyzed.The hydrodynamic control characteristics of hot water flow and pipeline pressure drop in solar hot-water circulation system is studied.Based on the model predictive control method,a dynamic maximum production point tracking method for a solarboosted biogas energy generation system is proposed.Taking the agricultural greenhouse micro-grid demonstration project in mountainous area of Hunan as a practical example,the proposed method can effectively solve the problem of low greenhouse crop yield under the cold climates,which improves the sustainable supply capacity of multiple energy sources.Secondly,the orderly energy consumption optimization model and strategy for multienergy load in agricultural greenhouse is proposed.Based on the temperature thermodynamic model,the thermal equilibrium equation between the greenhouse system and the external environment is established.The photosynthetic effective radiation and carbon dioxide requirements of typical greenhouse crops in different growth stages are analyzed,and the energy demand of dry matter accumulation of crops on various energy forms such as light,heat and carbon in different growth stages are derived.On this basis,a quantitative method of energy consumption flexibility with reducible and translational load in greenhouses is formed.The orderly energy utility optimization model and strategy of multi-energy loads in agricultural greenhouses are constructed with the goal of minimizing the energy consumption cost per unit yield of crops.The case study results show that the electricity cost of the proposed strategy can be reduced by 26.56%.Finally,the source-load collaborative dispatching optimization method of agricultural greenhouse integrated energy system is proposed.Based on the multi-port EnergyHub model,a multi-energy complementary greenhouse integrated energy system is established,which reveals the multi-energy conversion and interactive coupling characteristics of solar-biogas to agricultural loads in electric-thermal-carbon multi-energy flows.Based on the solar-biogas complementary characteristics on the energy supply side and the flexibility of multi-energy loads on the demand side,the dispatch of solar collector heat supply,the output of biogas combined heat and power generation units,and the demand response of electric-thermalcarbon energy loads are optimized.The source-load collaborative dispatching optimization method of agricultural greenhouse integrated energy system is proposed with the goal of minimizing the electricity cost under agricultural time-of-use electricity price.The case study results indicate that the proposed method can accelerate the dry matter accumulation of crops and effectively reducing the energy consumption and electricity cost per unit yield of greenhouse crops.In summary,this paper proposes the maximum production point tracking method for a solar-boosted biogas energy generation system on the energy supply side,the modeling and orderly energy utility optimization of agricultural greenhouse multi-energy loads on the demand side,and source-load collaborative optimization model and method of the agricultural greenhouse integrated energy system,which effectively reduce the energy consumption and electricity cost per unit yield of crops.