SET Proceedings 2978-4387 Caravel Press 10.65582/set.2010.002 2010.002 Numerical Study on the Energy Performance of a Novel Direct Expansion PV/T Heat Pump (DX-PV/THP) System ChenHongbing RiffatS. B. MempouoB. Institute of Sustainable Energy Technology, The University of Nottingham, Nottingham, UK School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, China 24082010 9 978-1-995850-04-7 1 9 24 August 2010 © 2010 Copyright WSSET 2010

A theoretical analysis of novel direct expansion heat pump system incorporating a PV/T solar collector acting as the evaporator is presented in this paper. The collector/evaporator is made of vacuum-tube-PV sandwich and the heat extracted from PV panel provides the heat source for the cooling fluid (R134a) passing through u-shape cooper tube of the collector; resulting in the reduction of the PV cells’ working temperature. This also improves the electrical and thermal efficiencies of the PV cells. Based on energy balance of each parts of the vacuum-tube-PV sandwich and the four main components of the heat pump system, mathematical models are developed to evaluate the energy performance of the heat pump and the electrical and thermal performances of the PV cells, under the climatic conditions of the City of Nottingham, UK. The simulation results indicate that the average monthly thermal and electrical efficiencies are 0.752 and 0.155 respectively, and the average monthly COP reaches 5.35.

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