一种新型复合压缩空气储能系统的热经济学分析

Thermo-Economic Assessments of a Novel Integrated Compressed Air Energy Storage System

为了避免压缩空气储能系统的蓄热过程中存在的问题,减少压缩热的产生及实现压缩热的高效利用,提出了一种新型复合压缩空气储能系统,建立了系统的热经济学模型,研究了系统在典型工况下的热力学和经济学性能,分析了关键参数对热力学性能的影响规律,并利用遗传算法进行了多目标优化。研究结果表明:系统在典型设计工况下的电-电效率和[火用]效率分别为63.86%和58.18%,膨胀机组和压缩机组分别占总[火用]损的17.3%和15.6%,系统的平准化度电成本为1.036元/(kW·h);参数敏感性分析表明,卡琳娜循环存在最佳蒸发压力使系统的热力学性能最佳,系统效率随着水气罐进气压力、储气罐最高压力和废热水温度的提高而提高,系统的储能密度随着循环压缩次数的增大而线性增大。多目标优化结果表明,系统的最优[火用]效率和平准化度电成本分别为59.1%和0.962元/(kW·h)。研究为压缩空气储能系统的设计提出了一种新的解决方案,系统在工业废热的综合利用方面具有较好的应用前景,分析和优化的结果可为所提系统的工程应用提供理论依据。

To avoid the problems of the heat storage process in the compressed air energy storage system,reduce the generation of compression heat,and realize the efficient utilization of compression heat,a novel integrated compressed air energy storage system is proposed in this paper.The thermo-economic model of the system is established,and the thermodynamic and economic performance of the system under typical working conditions is studied.The influence law of key parameters on thermodynamic performance is analyzed,and the multi-objective optimization is carried out by the genetic algorithm.The results show that,under typical working conditions,the electrical-electrical efficiency and the exergy efficiency of the system are 63.86%and 58.18%,respectively,while air expander and pre-compressors have relatively high exergy destruction,accounting for 17.3%and 15.6%of the total exergy destruction,and the levelized cost of electricity for the system is RMB 1.036/(kW·h).The sensitivity analysis shows that the optimal evaporation pressure exists in the Karina cycle to maximize the thermodynamic performance of the system.The system efficiency increases with the increase of the inlet pressure of the vessel,the maximum pressure of the reservoir,and the temperature of waste water,while the energy storage density of the system increases with the increase of the cyclic compression numbers linearly.The multi-objective optimization results reveal that the optimal exergy efficiency and levelized cost of electricity are 59.1%and RMB 0.962/(kW·h),respectively.This paper presents a new solution for the design of the compressed air energy storage system,the system has a good prospect in the comprehensive utilization of industrial waste heat,and the analysis and optimization results can provide a theoretical basis for the engineering application of the proposed system.