Photovoltaic Thermal Air Collectors: Recent Advances in Performance Enhancement and Solar Thermal Applications (Review)

In the recent years, photovoltaic thermal (PVT) devices have immensely grown in popularity. PVT devices harness clean energy and are considered the best alternative to renewable energy when considering the simultaneous generation of both useful heat and electricity, thus providing a higher overall energy yield and improved performance as compared to single-function systems. These devices use either air, water or nanofluid as coolant. Although much work has been done in the field of PVT systems using water/nanofluid as coolant, there is a gap in literature on the use of PVT air collector (PVTAC) for the same. The aim of this review is to study the development of these devices through a study of the various parameters such as mass flow rate, different absorber configurations, use of coatings and glazing on which the performance of such systems depends. This study is done with exergy efficiency as performance evaluator. This review also discusses the various applications of the PVT air collectors. It is to be noted that this study is focused primarily on the recent development in these devices. The conclusion offers merits and demerits of the system as well as recommendations for future scope of study.