Enhanced compression heat recovery of coupling thermochemical conversion to trigenerative compressed air energy storage system: Systematic sensitivity analysis and multi-objective optimization

Abstract

Compressed air energy storage system has been considered as a promising alternative solution for stabilizing the electricity production driven by intermittent renewable energy sources. However, the inefficient utilization of thermal energy within the compressed air energy storage system hinders the efficient operation of system. Therefore, a novel trigenerative system integrated compressed air and chemical energy storage system is introduced in this study. The proposed system transforms the compression heat to the syngas in the form of chemical energy to achieve energy level upgradation during the charging process, and recuperates the thermal energy at the exit of the gas turbine to increase the inlet temperature of the compressed air for electricity enhancement during the discharging process. The residual heat during the operation process is then conducted for producing cooling and heating outputs simultaneously based on the law of energy cascade utilization. A systematic parametric analysis is carried out to investigate the effects of critical parameters on system comprehensive performance. Furthermore, the multi-objective optimization is employed to find the optimal trade-off among the thermodynamic performance, economic attractiveness and environmental friendliness of the proposed system. The parametric analysis indicates that the operating parameters of air compressor and gas turbine affect the performance indicators of thermodynamic and economic significantly. Moreover, at the best trade-off solution selected by the TOPSIS method, the system reaches 42.96 % of exergetic round trip efficiency, 105.28 $/MWh of levelized cost of energy and 206.94 kg/MWh of CO2 emission per unit energy output.