Abstract
When evaluating the efficiency of heat pump systems, the most commonly used measure is the energy (or the first law) efficiency, which is modified to a coefficient of performance (COP) for heat pump systems. However, for indicating the possibilities of thermodynamic improvement, exergy analysis (or second law analysis) is needed. This study presents a procedure for exergy analysis of heat pump systems using energy, entropy and exergy balance equations. The proposed method is used to compare a ground-source heat pump system and an air-source heat pump system. Exergy efficiency values for both systems are calculated, and thereby exergy consumption in each of the system components are clarified to demonstrate the potential for improvements.
