Energy performance evaluation of a recycled water heat pump system in cool and dry climate zone

Abstract

This paper presents performance evaluation results for a recycled water heat pump (RWHP) system, which uses the recycled water from a municipal water system as a heat sink and heat source for heat pumps. The temperature of the recycled water, system heat flow, and efficiency were analyzed based on measured data from December 2014 through August 2015. The annual energy consumption of the RWHP system was compared with that of a baseline system-a conventional variable-air-volume system using a water-cooled chiller and a natural gas-fired boiler, both of which meet the minimum energy efficiencies allowed by ASHRAE 90.1-2013. The analysis results indicate that, on an annual basis, the RWHP system has avoided 50% of source energy consumption, reduced CO2 emissions by 41%, and saved 34% in energy costs compared with the baseline system.