HelioClim-3 database

HelioClim-3 is a satellite-derived solar radiation database exploiting Heliosat-2 method to estimate a "cloud index", based on the analysis of the Meteosat Second Generation satellite images in the visible band.

HelioClim-3 Real-time and Forecast service

This service provides irradiation data for today and tomorrow with a time step ranging from 1 minute to 1 day.

We enhance the native spatial resolution of MSG by computing inside a MSG pixel the irradiation variation due to the altitude and to the shadow of the horizon for a specific point. The relief used to compute the shadowing is obtained from the SRTM digital surface model, with a spatial resolution of ~100 meters.

The service provides global, direct, and diffuse solar radiation at horizontal, tilted and normal planes.

HelioClim-3 is updated in real time, and time series are completed until the end of the day using a "persistence model". At least one slot after sunrise must be available to trigger the computation. Tomorrow forecast has been developed using a "similarity model" based on a statistical study of the long term HelioClim-3 database.