Techno-economic and environmental performance of a novel poly-generation system under different energy-supply scenarios and temperature and humidity independent control

Abstract

The stand-alone energy production for power generation, heating or cooling is an usual method for low-medium grade energy utilization. To enhance the energy utilization efficiency, a combined cooling, heating, and power (CCHP) system, which is based on two-stage vapor compression cycle (TSVCC) and organic Rankine cycle (ORC), is proposed with temperature and humidity independent control (THIC). The essential parameters are changed to enhance the CCHP performances based on the thermodynamic model constructed. Moreover, the cooling performance are evaluated under different energy-supply scenarios, and the coupling effects of the CCHP are demonstrated through the THIC strategies. The results display that when the return air and fresh air are treated with energy of corresponding grade respectively, the higher outdoor relative humidity and the lower fresh air ratios are beneficial for enhancing refrigeration performance. The adverse effects of condensation temperature on both the economic and environmental performance far surpasses that of sub-cooling degree. With a rise of 10 °C in condensation temperature and sub-cooling degree, the economic performance decreases by 27.89% and 3.7% respectively, while the environmental performance decreases by 24.33% and 0.35% respectively. Furthermore, the proposed system can be switched to variant models according to different strategies in seasons to improve efficiency of energy utilization, which could be used in engineering applications.