Determination of the heat transfer coefficient of PV panels

Highlights: • Wind effect on PV panel was examined. • Heat convection coefficient in poly crystal solar panel has been calculated. • The effect of air velocity on the cooling performance of PV panels was investigated. -- Abstract: In this study, the efficiency of the rear-panel air velocity in cooling was investigated based on the temperature and solar radiation in the environment where the panels are located. During the cooling of the panels, the rear-panel temperature decreases, and accordingly, the open-circuit voltage of the panels increases. At present, the most important losses in panels are due to the increase in panel temperature depending on the solar radiation and outdoor air temperature. In this study, the rear-panel temperature changes were observed at 0–5 m/s air velocities and 10–40 °C. The calculations reveal that in winter weather conditions, the temperature of the panels did not increase at a level that would require cooling. This study investigated the heat transfer from the surface depending on the outdoor air temperature of the rear-panel air velocity and the changing rear-panel temperature. The effect of different outdoor air temperatures on the rear-panel heat transfer is minimal. When the air velocity was 5 m/s and the outdoor air temperature was 10–40 °C, the heat transfer in the Poly Crystal Solar panel was calculated as 11.6 W/m²K.