Performance evaluation of sheet-and-tube hybrid photovoltaic/thermal (PVT) collectors connected in series

Photovoltaic-thermal (PVT) technology integrates PV and conventional solar thermal collectors. Here theoretical modeling and experiments were conducted to evaluate the performance of PVT collectors in series. Analytical expressions for N collectors in series were derived using basic energy balance equations and computer-based thermal models. We analyzed the outlet temperature of working fluid, PV module temperature, and absorber plate temperature of PVT collectors in series. In addition, the test setup of the performance of PVT collectors was established, including 36 PVT collectors in this experimental system and every six PVT collectors in a series. The thermal efficiency and electrical efficiency of the PVT collectors were evaluated. We validated the modelling prediction using experimental data and found a good concurrence between the measured and predicted data.