Experimental and numerical results from hybrid retrofitted photovoltaic panels

•The experimental study focuses on the feasibility of hybrid PV/T panels retrofitting.•The critical role of a thin layer of air between PV panel and back plate is evidenced.•The benefit of the addition of a conductive paste layer is analyzed via FEM simulations.•The use of wood ribs to stick the back plate represents a cheap effective solution.

The aim of present study is to investigate different methodologies to achieve a better contact between a photovoltaic panel and a thermal plate, in order to cool the PV panel by means of water in the perspective of coupling it with a heat pump. It is believed that this kind of system allows to obtain a higher energy efficiency. The analysis is developed both experimentally and numerically, testing different kinds of configurations in different operating conditions. Simulations are employed to analyze the effect of the variations of the contact resistance between the panel and the thermal plates, demonstrating that the use of a conductive paste increases the overall performance of the panel. Results show interesting possibilities in terms of retrofitting of existing photovoltaic panels by employing very simple solutions, such as to fix the thermal plate on the rear of the panel by means of wood ribs.