Cooling of Photovoltaic Panel Equipped with Single Circular Heat Pipe: an Experimental Study

The cooling process of photovoltaic (PV) panel is one the main issue in in the field of solar systems. The temperature of solar cells increases when solar radiation and also ambient temperature increase. Increasing the cell temperature reduces the electrical output power of the panels as well as their lifetime. To solve this problem, various methods have been provided for cooling the panels. One of these methods is the application of heat pipes. In this research, a PV panel equipped with thermosyphon heat pipe is introduced. The thermosyphon was connected to the back sheet of the panel to enhance the cooling effect of the PV system. Instead of using polyvinyl fluoride polymer, unlike conventional panels, an aluminum plate was used to connect the heat pipe to the back of the panel to have better cooling. In addition, to increase the heat transfer area between heat pipe and back surface of the panel, a special groove was drilled on the aluminum plate. Three different filling ratios (۲۵, ۴۵ and ۶۵%) of distilled water as the working fluid were used in thermosyphon. The best performance of the systems was obtained at ۴۵% of filling ratio, in which, the electrical power of the PV panel equipped with heat pipe was around ۳.۲% better than the conventional PV panel. In this case, ۶.۸ °C temperature difference was observed in the water tank connected to the condenser section of heat pipe which means that ۵۴ kJ heat was transferred to the water in the tank.

Keywords:

photovoltaic panel , Cooling , heat pipe , Thermal analysis , Electrical performance