Enhanced Site-Adaptation for Reliable PV Assessment: Comparative Study for Brazil and Germany
Abstract
While satellite-based irradiance methods typically offer high confidence levels, they may still show considerable discrepancies when compared with ground-based measurements. To mitigate this and improve the reliability of localized generation estimates, satellite data correction techniques (site adaptation) that integrate short-term ground measurements are employed. This paper proposes a method for enhancing the linear regression site adaptation method by incorporating solar irradiance band separation and clear-sky classification index (Kc) analysis. The methodology begins with data acquisition and control. Subsequently, a site adaptation method is applied, supplemented by a Kc analysis, data segmentation based on solar irradiance bands and error metrics are calculated for each case. A comparison analysis between a location in Brazil and in Germany is carried out. In all cases, the proposed methodology was able to significantly improve satellite bias on solar resource assessment. Additionally, results show that using two years of measured data offers significant improvements over a one-year period and could enhance the reliability of solar generation long term forecasts.
Keywords
Site adaptation, Solar radiation, Linear regression, Solar energy