Using Exergy Analysis Methodology to Assess the Heating Efficiency of an Electric Heat Pump

Abstract

The authors, using exergy analysis methodology, propose that it should consider not only the COP (coefficient of Performance) value of the electric power heat pump set (EPHPS/or HP set), but also the exergy loss at the heating exchanger of the HP set to assess the heating efficiency of the HP set and reduce the anergy at the heating exchanger of the HP set. Considering the quantity and quality transmission efficiency for the HP set, the authors defined three parameters to show the heating exergy loss and heating exergy efficiency for the HP set, presented an average heating temperature ranges for the heating exchanger with four different refrigerants, in which the HP set runs efficiently. Compared to the COP assessment standard, the authors attained a suitable average heating temperature range for the HP set more accurately. The authors concluded the following: 1) to assess the heating efficiency of a HP set or to define a better temperature range for the heating exchanger of a HP set, people should not only consider the COP value of the set, the characteristics of the refrigerants, but also the exergy loss and exergy efficiency at the heating exchanger; 2) it is not perfect to assess an HP set performance with only one parameter, COP, and 3) we would better improve the room structure and floor shape in order to heat the room well in a low temperature heating system.