Performance analysis of a solar-assisted heat pump water heater
Journal
Solar Energy
Journal Volume
74
Journal Issue
1
Pages
33-44
Date Issued
2003
Author(s)
Abstract
A modeling and system simulation of an integral-type solar assisted heat pump water heater (ISAHP) was carried out in the present study. The modeling and simulation assumes a quasi-steady process for all the components in the ISAHP except the storage tank. The simulation results for instantaneous performance agreed very well with experiment. The simulation technique was used to analyze the daily performance of an ISAHP for 1 year. It is shown that the daily total COP (COPo) is around 1.7 to 2.5 year around for the ISAHP, depending on seasons and weather conditions. COPo is higher than 2.0 for most of the time in a year and the daily operating time varies from 4 to 8 h. The online adjustment requirement of the expansion valve was also investigated using the present simulation technique. The analysis shows that the expansion device does not need to be controlled online. Using the 1-year simulation results, a universal daily performance correlation of the ISAHP was derived and shown experimentally to be applicable to another design of ISAHP. © 2003 Elsevier Science Ltd. All rights reserved.
Publisher
Elsevier Ltd
Type
journal article