Energy assessment and monitoring of a novel photovoltaic-thermal collector designed for solar-assisted heat pump systems

Hybrid photovoltaic-thermal (PVT) collectors have been widely investigated in recent decades since they ensure higher performances and compactness with respect to the two sub-components. In this study, a novel covered PVT water collector, specifically designed to be coupled with heat pumps, is presented. The PV-cells are directly laminated on the aluminium roll-bond absorber without the usual front glass layer, while a glass cover is added after the lamination, creating an air gap with the PV-absorber laminate. The novel collector has electrical features similar to those of uncovered PVTs, in which the front glass layer is laminated in contact with PV-cells and even better performances than a traditional covered collector, which has a second glass cover on top. The electric performances of the PVT, operated in stand-alone mode and solar-assisted mode, were monitored and compared with a traditional PV module, obtaining interesting results in both conditions. In particular, the novel PVT showed comparable and even better electric performances than the traditional PV when combined with the heat pump, thanks to PV-cells active cooling. The work proves that the proposed manufacturing technique could lead to a new generation of hybrid collectors, which may achieve competitive performances when integrated with heat pumps.