Photovoltaic cogeneration: theoretical and experimental analysis of an innovative module

Commercial photovoltaic modules have nowadays an efficiency around 12%-15%. It means that the most relevant part of solar radiation is lost. Such a remark gets more importance if the active surface is located in an urban environment, where the availability of surfaces exposed to the sun is scarce if compared to the buildings thermal loads. PhotoVoltaic / Thermal cogeneration (PV/T) aims to utilize the same area both for producing electricity and heat. Different kinds of PV/T modules have been theoretically and experimentally investigated by the authors in recent years, but all were made of a Photovoltaic layer physically coupled (by high thermal conductive glues or films) to a Thermal plate (copper or aluminium). The paper reports on the construction of an innovative module with a semitransparent PV layer substituting the glass of a thermal collector; it was studied by a numerical simulation developed in Visual Basic to evaluate the energetic viability of the proposed PV/T technology. The collector was experimentally tested outdoor during summer 2010 at the Department of Management and Engineering (University of Padua, Italy) in different conditions of solar radiation, inlet fluid temperature and flow rate