Experimental study and performance analysis of the photovoltaic system output under real weather conditions

The aim of this study is to evaluate PV output, considering PV module temperature and real meteorological parameters. An experimental investigation was performed in warmest month, July, and the following parameters were measured: PV module temperature, PV voltage and current, solar irradiation, air temperature, and wind velocity. It was shown that increasing PV module temperature above 25 °C leads to voltage drops and decreased electrical efficiency. The minimum measured average daily PV module temperature was 40.86 °C and the maximum was 42.59 °C. It is shown that when the PV module temperature exceeds 25 °C, the electrical efficiency starts to decrease at a rate of 0.449 – 0.455%/°C. It can be concluded that for approximately 2.2 °C above 25 °C leads to a 1 % reduction in the PV module’s electrical efficiency. These results are significant for designing PV systems and evaluating energy yield considering the climate parameters in which they will operate.