Energy, environmental and economic evaluations of a CCHP system driven by Stirling engine with helium and hydrogen as working gases

Abstract

Abstract In this study, with a comprehensive approach, energy, economic, and environmental evaluations of a combined cooling, heating and power (CCHP) generation system driven by Stirling engine with working gases of hydrogen and helium were performed. This system can be used for residential applications. The engine was analyzed using the non-ideal adiabatic model, and two beta type Stirling engines were suggested in the CCHP system. Also, the energy analysis of the absorption chiller was presented with utilizing the waste heat of the engine. Then, the impacts of important specifications of the Stirling engine including: temperature of heater, length of regenerator, engine rotational speed, and type of working gases on the COP of absorption chiller, CCHP efficiency, Trigeneration Primary Energy Saving (TPES), Operational Cost Reduction (CR), and Trigeneration CO2 Emission Reduction ( TCO 2 ER ) relative to conventional energy supply systems were studied. Finally, at the appropriate conditions, the values for parameters of electrical power: 15.24 kW, 22.52 kW, heating capacity: 19.65 kW, 21.65 kW, cooling capacity: 12.65 kW, 14.43 kW, COP: 0.644, 0.667, CCHP efficiency: 70%, 72.29%, TPES: 24.05%, 31.3%, TCO 2 ER : 31.06%, 38% and CR: 75.53%, 78.8% were obtained for helium and hydrogen, respectively.