Photovoltaic/thermal (PVT) systems: A review with emphasis on environmental issues

The present article is a review about PVT (photovoltaic/thermal) investigations with emphasis on studies which include environmental issues about PVT technology. The references analyzed are presented according to certain criteria (e.g. the type of the system: BA (building-added), BI (building-integrated), CPVT (concentrating PVT), etc.). The literature review shows that most of the investigations examine EPBT (energy payback time) and CO2 emissions. In terms of the types of the systems, most of the studies are about BA PVT/water installations for domestic applications and thereby, more studies (which include environmental issues) are needed e.g. about BIPVT, CPVT, BICPVT and PVT systems for different applications (apart from the building sector), for example industrial. In addition, a separate section with factors which influence PVT from environmental point of view (PV cell material, heat transfer fluid, concentrators, alternative materials, etc.) is included. A critical discussion about these factors is also provided, explaining how they influence the environmental profile of a PVT system. Moreover, explanations about different methods and indicators which provide (or which can provide as a future prospect) useful information for PVT (from environmental point of view) are also presented.