Performance analysis and optimization of a combined cooling, heating and power system based on active regulation of thermal energy storage

The energy storage unit can significantly address the issue of mismatch between the energy supply and demand of the combined cooling, heating and power (CCHP) system. Therefore, this article proposes a micro-gas turbine coupled with low-concentrating photovoltaic/thermal CCHP system with thermal energy storage active regulation, which can change the thermoelectric output ratio of the micro-gas turbine. The impact of the volume of the heat storage tank and the changes in ambient temperature on the system's performance is analyzed. This system is optimized with the objective functions of primary energy consumption saving rate, carbon dioxide emission reduction rate, total annual cost saving rate and exergy efficiency maximization. The results indicate that increasing the volume of the thermal energy storage tank enhances the exergy efficiency. Furthermore, an increase in ambient temperature can improve the objective functions. The optimum comprehensive performance of this system is achieved when the thermal energy storage tank volume is 40 m3 and the gas boiler capacity is 241.16 kW. With the thermal energy storage active regulation, the primary energy consumption, carbon dioxide emissions and annual total cost of the system decline by 2.24 %, 2.12 % and 1.48 %, and the system exergy efficiency improves by 1.72 %.