Investigation of the Shading Effect on the Performance of a grid-connected PV Plant in Samsun/Turkey

In photovoltaic (PV) systems, power generation is significantly affected by partial or complete shading of solar panels. In this study, the effects of shading caused by a transformer building on the performance of a PV array in an on-grid solar power plant were investigated under real operating conditions. The performaces onf the shaded and the unshaded array were regularly observed under the outdoor climatic conditions on clear and sunny days for 12 months. As a result of the evaluation of performance data, the total power loss due to the transformer building was calculated to be 307 kW (0.66%) in the shaded 30 kW-PV array after one-year operation of the power plant. It is obvious that the energy loss caused by the shading effect will reach up to power in MW scale when considered since photovoltaic energy systems have lifetime up to 30 years. This observation underlines the importance of the operational units when designing a PV power plant.