Efficient single glazed flat plate photovoltaic–thermal hybrid collector for domestic hot water system

This paper deals with the design of a single glazed flat plate Photovoltaic–Thermal (PV–T) solar collector. First, the thermal and electrical performances of several single glazed flat plate PV–T concepts based on water circulation are investigated, using a simple 2D thermal model, then different ways of improvement are presented. It mainly consists in focusing on the heat transfer between PV cells and fluid, and also on the optical properties of materials. Thus, the most appropriate concept configuration has been identified and suitable material properties have been selected. A prototype collector has been designed, built and tested. A high thermal efficiency was reached at zero reduced temperature. For this level of thermal efficiency, the corresponding electrical efficiency has is lower than efficiency of a standard PV panel using the same technology. However, this solar PV–T collector is reaching, in these standard conditions, the highest efficiency level reported in the literature.

► PV-T collectors convert solar energy into heat and electricity.
► We studied several configurations of glazed PV-T collector using a simple 2D model.
► We built a prototype collector based on improved materials and tested it.
► The results show a significant improvement of the thermal efficiency of our collector in comparison to previous work on PV-T collectors.