Solar energy potential in Freiburg, Graz, Maribor, Banja Luka, Nis, and Athens

This paper presents a comparative analysis of solar energy potential for six different cities, in six different countries in Europe: Freiburg (Germany), Graz (Austria), Maribor (Slovenia), Banja Luka (Bosnia and Herzegovina), Nis (Serbia), and Athens (Greece). Data processed in this work are accessed from Photovoltaic Geographical Information System (PVGIS). Photovoltaic technology is crystalline silicon, and installed peak photovoltaic power is 5 kWp. The aim of the work is to find out whether there are statistically significant differences among the cities in relation to monthly energy production in regard to different types of photovoltaic system (fixed - free standing, fixed - building integrated, inclined, and two axis solar power plants). The work is based on four hypotheses. The estimation of solar energy production in different regions is very important for determination of potential regions suitable for generation of renewable and sustainable energy.