Parametric modeling and simulation of photovoltaic panels with earth water heat exchanger cooling

Abstract

Photovoltaic (PV) systems work efficiently up to a certain cell temperature and exhibit efficiency losses and long-term degradation if the cell temperature exceeds a certain limit. The rise in temperature can be controlled with the help of cooling techniques to maintain cell temperature within limit. In the current research, a novel cooling technique termed earth water heat exchanger (EWHE) is designed and simulated by varying its operating parameters, which includes mass flow rate, length, pipe materials, and diameter of buried pipe. Results showed that peak PV panel temperature goes up to 79.31 °C without any cooling and drops to 47.13 °C with the help of EWHE cooling for optimum flow rate of 0.018 kg/s. At this flow rate, with decrease in panel temperature, the PV power also increased by 23.16 W with EWHE cooling. The comparative study between three different EWHE pipe material shows that the performance of coupled (PV/T + EWHE) system hardly depends on the properties of these materials. It is also observed that there is an inverse correlation between the EWHE pipe length. The variation in pipe diameter shows that the PV temperature decreases with an increase in pipe diameter. The PV/T system along with EWHE may be used for the purpose of PV power plants cooling in the hot and semi-arid regions of western Gujarat and Rajasthan (India), where solar irradiation is ample and ambient temperatures are very high.