基于固体填料床的泵热储能系统热-经济性分析

Thermo-economic analysis on the pumped thermal energy storage system based on the solid packed beds

泵热储能技术因其具有大规模化、成本较低且无地理条件限制的优势,在未来电力系统中扮演着十分重要的角色。针对采用固体填料床且基于可逆焦耳-布雷顿循环的泵热储能系统,开展了不同设计参数对系统热-经济性的影响规律研究,结果表明:系统综合效率随着最大充电温度、做功部件多级效率和填料床孔隙率的增加而升高;当选取氦气为工质,磁铁矿为储热介质,且最大充电温度为850 K时,多级效率为92%,填料床孔隙率为46%时,得到最大综合效率72.45%。系统平准化储能成本随着最大充电温度和做功部件多级效率的增加而降低;当选取氦气为工质,磁铁矿为储热介质,且最大充电温度为850 K时,多级效率为92%,填料床孔隙率为40%时,可获得最小平准化储能成本0.211美元(/kW·h)。

Pumped thermal energy storage technology will play a critical role in the future electric power system due to its large scale,low capital cost and no geographical constraints.A pumped thermal energy storage system based on solid packed beds and the reversible Joule-Brayton cycles and the effects of distinct design parameters on the system's thermo-economic performance were investigated.It can be revealed that the system roundtrip efficiency increase with the gowing of the maximum charging temperature,polytropic efficiency of the machines and porosity of packed beds.Using helium as the working fluid and magnetite as the storage material,the system's maximum roundtrip efficiency can be as high as 72.45%when the maximum charging temperature,polytropic efficiency of the machines and porosity of packed beds are 850 K,92% and 46%,respectively.The levelized energy storage cost of the system reduces with the rising of the maximum charging temperature and polytropic efficiency of the machines.Using helium as the working fluid and magnetite as the storage material,the minimum levelized cost energy storage will bottom at 0.211 dollar(/kW·h)when the maximum charging temperature,polytropic efficiency of the machines and porosity of packed beds are 850 K,92%and 40%,respectively.