Thermo-economic optimization of a high-performance CCHP system integrated with compressed air energy storage (CAES) and carbon dioxide ejector cooling system

Abstract

Abstract A novel compressed air energy storage (CAES) system integrated with combined cooling, heating, and power (CCHP) is proposed and investigated in this study. The system under investigation uses carbon dioxide as the working fluid for the CCHP system to produce cooling from an ejector refrigeration subsystem and heating. The investigation here includes a detailed thermodynamic and thermo-economic analysis while evaluating the system s CO2 emissions in the operating phase. By changing the design parameters, the influence of their variation on system performance was investigated next. Finally, the proposed CAES-CCHP system is optimized for three objective functions, including the exergy efficiency, the normalized carbon dioxide emissions, and the total cost rate using the non-dominated sorting genetic algorithm- II (NSGA-II). The results of the investigation for the base case showed that the system uses 72.02\xa0MW of power during the charging phase for the compression of air and produces 136.56\xa0MW of power during the discharging phase by the gas and CO2 turbines. The CCHP system can produce a cooling load of 1.96\xa0MW and a heating load of 65.8\xa0MW. Optimization results showed that for the optimal Pareto solution, the system has a total cost rate, exergy efficiency, and normalized CO2 emissions of $4817.73/h, 68.19%, and 157.09\xa0kg CO2/MWh, respectively.