Investigation on part-load operation characteristics and adaptability of the GT-CO2 composited multi-generation system for distributed applications

The distributed energy system encounters severe challenge on frequent adjustment on cooling and electricity load. In this study, an instructive GT-CO2 composited multi-generation system that composed of GT and bottoming CO2-based cogeneration system is proposed to improve the energy efficiency and adaptability oriented toward diversified electricity and cooling demand in distributed applications. An evaluation framework based on both design and off-design conditions is developed to investigate the operating characteristics, available operating strategies, and flexible regulation range of the composited system under global operation conditions. The proposed system demonstrates satisfactory performance on both energy efficiency and operating flexibility. In the design condition, the primary energy saving ratio is 23.5 %, which is 8.0 % higher than traditional distributed scheme with GT and absorption chiller. Besides, the efficient operation conditions can be enhanced from 30.3 % to 63.6 % and 83.8 % for the composited system with turbine inlet temperature control and inlet air throttling control strategy respectively under full operation conditions. Broader feasible regulation range with higher efficiency for electricity and cooling outputs is also found in the composited system, proving the promising potential in scenarios with diversified energy demands.