Electrical characterization and comparison of a novel covered PVT collector

Hybrid photovoltaic-thermal (PVT) collectors have been widely investigated in recent decades, since they include in a single device the two most diffused solar technologies: photovoltaic and solar thermal, ensuring higher overall performances and compactness with respect to separated components. In this study a novel PVT collector, able to reduce the optical losses as well as to increase the heat transfer toward the working fluid, is presented. In detail, the PV cells are directly laminated on the aluminium roll bond absorber without the front cover glass, which is added at the end of the lamination process above a spacer, creating an air gap. Obtained results showed that the novel collector maintains similar electrical characteristics to an uncovered PVT and even better performances than a traditional covered collector. Moreover, due to the air gap between cells and glass, the overall thermal losses from the surface are heavily reduced, with benefits in terms of thermal efficiency. The work proves that the direct lamination of PV cells above a roll-bond absorber within an air gap with a single glass layer as a cover could lead to a new generation of hybrid PVT collectors.