Direct Normal Irradiance for CSP Based on Satellite Images of Meteosat Second Generation
We present a method to derive the direct normal irradiance (DNI) from MSG data. For this, we apply the Heliosat method and a new model for the direct fraction of the irradiance. The clear sky irradiance is mainly determined by the aerosol optical depth (AOD) and water vapour content, which are taken from suitable climatologies. The accuracy of satellite derived DNI data has been analyzed for Spanish sites, more sites will be evaluated within the project SESK (Standardisierung der Ertragsprognose Solarthermischer Kraftwerke – standardization of yield prognosis for solar thermal power plants). As for concentrating solar power (CSP) the frequency distribution of DNI is of special importance, special attention is given to correct modeling of this feature.