The use of fossil energy sources greatly damages the environment. Moreover, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water and biomass) in energy generation. Huge amounts of energy (1100-1300 kWh/m2 per year) arrive at the earth from the sun, and are utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV – panels. This can be fed into a grid. At the University of Debrecen is a solar energy power plant from September 2005 in operation. The electricity performance of the incorporated PV-panels (Kyocera, Dunasolar, and Siemens) are 8.64 kW. The are of PV – panels is 110 square meter. With the aid of the data storage, the tension, current, temperature of the PV-panels, global radiation, air temperature, wind speed, wind direction and the achievement is measured by the ac network. The effect of the shading on the performance of the PV – panels and the solar energy power plant is examined. The analysis and the graphic representation of the experiment results are carried out with SPSS per grief. We produced per grief.