Two-stage Optimal Design For The Renewable Energy Sources Integrated Combined Cooling,Heating,and Power System

Energy shortage and environmental destruction are double crisis around the world today,to develop solar and biomass-based renewable energy sources and distributed energy supply system is a significant way to solve the problem.The renewable energy sources integrated combined cooling,heating,and power(RES-CCHP)system based on the energy cascade utilization principle can provide users with three forms of energy:cooling,heat and electricity.It not only improves energy efficiency and renewable energy consumption rate,but also effectively reduces greenhouse gas emissions,which has great potential for development.Thence,this paper focuses on the RES-CCHP system,studies the uncertainty of renewable energy and the operating characteristics of the system,and establishes a two-way interaction mechanism between system capacity configuration and operation strategy.Furthermore,a two-stage optimization design method for RES-CCHP system is proposed,which effectively improves the overall performance of the system.Firstly,this paper described the structural composition and design principles of the RES-CCHP system,and analyzed the uncertainty of solar energy and biomass energy,as well as the characteristics of the variable operating conditions of internal combustion generators.Therefore,the model of the RES-CCHP system was established,and the evaluation criteria of the system were put forward to lay the foundation for the research of optimization design.Secondly,based on the proposed structure of RES-CCHP system,this paper explores the impact of renewable energy uncertainty on system capacity configuration and operation strategy.The logical relationship between capacity configuration and operation strategy is analyzed.The idea of nested optimization is used to realize the two-way interactive feedback between the two levels,and the two-stage optimization design architecture of capacity and operation is constructed.Selecting the comprehensive optimization of energy,economic and environmental indicators as the goal,we established a two-stage optimization design model,and used genetic algorithm and nonlinear programming method to solve the optimal equipment capacity configuration and operation strategy.Finally,taking the annual load of a suburban farm in Jinan as an example,the advancements of the two-stage optimal design method are verified,and the optimization design method based on single operation strategy is compared.The results show that the equipment capacity configuration and operation strategy after two-stage optimization design can make the system output match the user load better,further improving the energy,economic and environmental indicators of the system.This proves that the two-stage optimization design method are advanced.