Analysis of novel passive cooling strategies for free-standing silicon photovoltaic panels

Silicon-based photovoltaic (PV) panels are sensitive to operating temperatures, especially during exposure to high solar irradiation levels. The sensitivity of PV panels is reflected through the reductions in photovoltaic energy conversion efficiency (electrical efficiency) and in PV panel lifetime due to thermal fatigue. In this study, different and novel passive cooling strategies were proposed and numerically investigated for the case of 50-W market-available free-standing silicon PV panels. The focus of the research was to examine the effect of the proposed modifications on the temperatures of the specific PV panel layers as well as on the velocity contours. The used numerical model was upgraded based on a previously developed numerical model that was validated through an experimental manner. Three different passive cooling scenarios were numerically investigated, and the most promising one was the case where the PV panel was provided with slits through the front PV panel surface resulting in a reduction of about 4 °C for the PV panel operating temperature. The other examined cases proved to be less effective with the detected temperature reduction being less than 1.0 °C. The consideration of novel PV panel frame materials was found to be a viable possibility. It was also found that all the proposed modifications can generally lead to the performance improvement in the PV panels and reduce the materials spent on the production of commercial PV panels.