Analysis of compressed air energy storage system coupled with thermal storage and photothermal

Abstract With the increasingly prominent issues of environmental pollution and resource depletion, vigorously developing renewable energy has become an important consensus among countries. Addressing the inherent intermittency of renewable energy sources, vigorously developing energy storage has become a top priority. The AA - CAES system coupled with photothermal energy storage can expand the application scenarios of AA - CAES power plants and improve system cycle efficiency. This article conducts research on AA - CAES technology coupled with high-temperature thermal storage and photothermal energy storage (CAES - HTPT) for large-scale CAES power plants above 100 MW. A thermodynamic model for a coupled tower solar collector system is established. The thermodynamic model analyzes the temperature, pressure, and other related thermodynamic parameters of major equipment such as compressors and expanders. By analyzing the operational characteristics and thermodynamic performance of CAES - HTPT, the CAES - HTPT system achieves an energy efficiency of 53.7 %, and the conversion factor of electricity storage is 1.008. Exergy analysis of CAES - HTPT is performed, revealing that the cooling unit experiences the greatest exergy loss, totalling 24234 kW, which represents 53.9 % of the overall exergy loss of the system.