Modeling And Optimization Of Distributed Energy System With Complementation Of Multiple Energy

In response to the problems of energy shortage and carbon emissions caused by the acceleration of industrialization and urbanization in recent years,Chinese government has put forward the action plan taking Energy Internet as an important strategy to promote energy revolution,which aims to raise the proportion of renewable energy,promote the clean and efficient use of fossil energy,as well as improve the comprehensive energy efficiency.Against this background,distributed energy system(DES)with complementation of multiple energy has become the focus of energy engineering,in which the optimization of installation capacity and operation strategy for DES is the most important technical problem.Whether the designed capacity is reasonable and the operation strategy is scientific,greatly affects the actual efficiency and economic benefits of the system.By analyzing the definition and basic structure of the Energy Internet,this paper expounds that DES with complementation of multiple energy is an advanced energy system consisting of energy production equipment,energy conversion equipment and energy storage equipment,which is based on primary energy of natural gas and integrates renewable energy locally to satisfy various terminal energy demand.By decomposition modeling,the multi-objective optimization model for DES with constraint of hourly energy balance is established,considering annual total cost,primary energy consumption and carbon dioxide emissions.The model can optimize installation capacity and hourly operation strategy,which is applied for design and planning of DES with complementation of multiple energy.An illustrative case study of one park is given to present effectiveness of the proposed model.According to terminal energy demand,energy price and energy resource condition of the park,the optimal installation capacity and operation strategy are obtained by optimization model.Compared to traditional energy system,both economic and environmental benefits in the optimized DES have been significantly improved.The result shows that annual total cost,primary energy consumption and carbon dioxide emissions can be respectively reduced 8.2%,19.6% and 43.7%.Meanwhile the primary energy ratio increases from 0.638 to 0.793.On the basis of case study,the paper makes further study on the DES with complementation of multiple energy from the aspects of energy price,renewable energy fluctuation,key equipment,and power grid connection mode,which further confirms the practicability of the optimization model,and provides theoretical basis and technical guidance for the implementation of relevant projects.