Indoor and Outdoor Testing of an Unglazed PVT Collector

Abstract

Photovoltaic-Thermal (PVT) collectors are multi-energy components that convert solar radiation into both electricity and heat. In fact, PVT collectors make possible use of the large amount of solar energy “wasted” in PV modules as usable heat in a thermal system. Therefore, PVT collectors represent in principle one of the most efficient ways to use solar energy (cogeneration effects). However, such a concept still faces various barriers due to the multidisciplinary challenges involved (material, semi-conductors, and thermal conductivity) and to the complexity of the technical requirements implied in such concepts. The electrical energy yield of a PV module depends on the temperature behaviour of the solar cell technology. In a PVT collector, the fluid in the heat exchanger may reduce the solar cells temperature and so increase the electrical energy yield of the PV module. In this study, a so-called unglazed PVT - which is essentially a PV module with a heat exchanger plate on its back side - is investigated by means of indoor and outdoor measurements at two different test institutes: SUPSI, specialized on PV testing and SPF, specialized on thermal collector testing.