Determination of optimum tilt angle for solar panels: case study for Eastern Anatolia Region of Turkey

The increase in energy demand has led to an increase in the tendency towards alternative sources to fossil fuels. Solar energy stands out as an alternative energy source. This study was conducted to increase the energy production efficiency in solar energy system investments to be made in the Eastern Anatolia region. For this purpose, Erzurum, Kars, Iğdır, Ağrı and Muş provinces were taken into consideration. The effects of monthly, seasonal, six month and annual changes in panel tilt angle on panel performance were investigated. When determining the monthly optimum tilt angle, PVGIS and HW methods were first used. For other cases, the PVGIS method was used. As a result of the calculations, it was seen that the maximum angle difference between the PVGIS method and the HW method was seen in the summer months and its maximum value was 13.45° in June in Ağrı province. The minimum angle difference was calculated as 0.01° for September in Kars province. In addition, compared to the tilt angle being 0°, an increase of 17.16%, 16.32%, 16.03% and 12.26% in energy production was achieved when the optimum tilt angle was changed monthly, seasonally, six month and annually, respectively. As a result of this study, it was determined that maximum energy production was achieved by changing the panel angle monthly, and it was concluded that the most efficient angle change period in solar panel installation is monthly.