Evaluation of Photovoltaic Microgeneration Systems Connected to Utility: Cases Studies in Petrolina

This work evaluated the performance of small-scale photovoltaic systems installed in Petrolina city, Brazil, operating under different meteorological conditions, through real production measurements, electrical quantities, inverter efficiency, also merit indices such as final yield and capacity factor. The measurement data showed the versatility of the inverters under different loading conditions, as well as correct operation in face of phenomena such as anti-islanding and clipping. It was verified that changes in meteorological conditions don’t affect the efficiency, remaining almost always higher than 95%, except for loading levels lower than 5%. The merit indices enabled the comparison between different photovoltaic systems, confirming the high energy potential in the Brazil northeast, regardless of the orientation used for the photovoltaic modules. The comparison between the actual production and the generation projections, revealed that the new irradiation indices, provided by Reference Center for Solar and Wind Energy Sérgio de S. Brito (CRESESB), present better agreement with the real data, allowing more reliable projection for photovoltaic generation.