Research On Comprehensive Evaluation And Capacity Of User-side Energy Storage System

Recent years,the programmatic documents of energy storage field in our country have successively issued.It clarifies the independence status of energy storage in the electricity market,encouraging the development of user-side energy storage,which marks that the user-side energy storage will enter the large-scale commercial stage.However,the user-side energy storage system still exists the problems of high cost and low efficiency.In order to promote the commercialization process of energy storage system and improve the benefits by user-side energy storage under the premise of reducing investment costs,it is necessary to analyze the benefits of userside energy storage and propose an effective comprehensive evaluation method of user-side energy storage.First,the annual cost per unit power of the energy storage system is modeled based on the whole life cycle model,and the residual value is introduced to improve the model.Then,analyzing the annual income for the energy storage system installation of large industrial users based on the two-part tariff,and establishing a government subsidy model according to the government subsidy policy for user-side energy storage in recent years.A complete user-side energy storage cost-benefit analysis system is established,and comparing the annual cost per unit power of four kinds of battery energy storage.Analyzing the sensitivity and proposing the measures to reduce costs.Finally,according to the return of investmentof users,analyzing the energy storage income,initially proposing the energy storage scheme suitable for users.Secondly,establishing the comprehensive evaluation system for the selection of user-side electrochemical energy storage.Based on the grounded theory and fuzzy Delphi method,the index system including economy,technology and environment was constructed and screened successively.The CRITIC-AHP was adopted to improve index weight calculation.The utility values of lead-acid battery,sodiumsulfur battery,lithium-ion battery and liquid flow battery were obtained from MARCOS method,and then verified by TOPSIS method.Finally,a decision optimization model is proposed for the configuration of lithium-ion battery energy storage of typical large users,which improving the economy.The configuration results were obtained through the double-layer optimal configuration model,and then the results were optimized by the decision optimization model to obtain the energy storage power and capacity configured when the user profit reach the highest.Verifing the rationality and effectiveness by examples.