The economic life of Solar Power Plants (SPP) is accepted for more than 20 years and this point is taken into account in financial analysis. The cumulative effect of very small changes in the efficiency of a system that will generate energy for 20 years increases significantly over the years. SPP efficiency determines the losses in the generated energy. The failures in SPPs have a serious impact on the reliability of the system and the energy balance. Because of this, the energy losses produced by the SPP plant directly depend on two major factors. These factors are plant failures and production inefficiencies in photovoltaic (PV) panels. To know the negative impact of energy losses in PV plants, contributes to optimization in maintenance and design and increases efficiency in power production. In this study, probable losses in SPPs are classified and examined and the possible consequences of these losses and their effects on SPP performance are explained. In addition, by using the actual data in the operation and maintenance follow-up of many power plants, error rates grouped by the deficiencies in energy balance are achieved. According to these results, the process in the system under test, 67415 MW of power plant and 59211 MW of power plant has been obtained, resulting in a total 87.83 percent difference.