Distributed dynamic modelling with experimental validation on a photovoltaic solar-assisted heat pump

Abstract

The photovoltaic/thermal solar-assisted heat pump is a system that directly integrates a Rankine refrigeration device with a photovoltaic/thermal solar collector. A specially designed direct-expansion PV evaporator is employed in the system to acquire thermal energy and electricity from solar radiation simultaneously. In this paper, a distributed model is presented that describes the dynamic performance of the system. Numerical simulation was performed with instantaneous solar irradiance and ambient temperature based on the model. A testing rig was built in Hefei, China, and experiments were conducted to verify the model. The results show that high photovoltaic and thermal performance can be obtained by the system. The average electrical efficiency is around 13.02 per cent. The output electricity is about 85.5 per cent of the power consumption, which means that the system can offer most of the power consumed by itself. Neglecting the heat loss of the water box, the highest coefficient of performance (COP_c) can reach up to 7.3 and the average value is around 3.41. Comparisons between the simulation results and the experimental measurements show that the model is able to give satisfactory predictions.

Keywords

photovoltaic/thermal solar-assisted heat pump distributed model coefficient of performance electrical efficiency

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