Abstract
To reduce energy consumption utilizing heat recovery systems is increasingly important in industrial applications. The screening of refrigerants is discussed with a case study for high-temperature heat pumps in this study. The overall coefficients of performance of four different cycle configurations to increase water temperature up to 160℃ using waste heat of 80℃ are thermodynamically compared for three refrigerants. This case study suggests that the multiple stage cycle reduces throttling loss and exergy loss in condensers and achieves the highest overall COP with a refrigerant having the critical temperature about the target outlet water temperature. Cascade cycles bring relatively high COP and also advantages in practical situations.
