SOLAR RADIATION Maps in real time

Last update: April 2020


Subscription to 15 min Global Horizontal Irradiation bitmap Maps in Wh/m² and in TIFF format delivered in real time (h-15 min) on a given area, during daylight time from 3:00 TU to 20:45 UT 


  • Service operational since March 2011
  • Spatial resolution and project: Meteosat Second Generation
  • Delivery: Automatic access with wget type command on the SoDa servers. The Customer is identified through a login and password. A mirror backup server is available to increase the reliability of the service.
  • UV in real time: please note that we also provide UV maps in real time.

In practice


The Customer communicates the rectangular box over the area cover by the service.


To limit the files size, the GHI values are divided by a factor of 1.2 to be stored in 8 bit TIFF format, leading to the approximate precision of 1 watt.

It is also possible to generate GHI maps with a 10^-2 precision in 16 bit TIFF images.

Archive: please note that the Hc3v5-15mapGHI maps are conserved for the last 4 weeks.


The Hc3v5-15mapGHI includes the post-processing layers that are available in the time series HC3v5. Here they are:

  1. Each pixel is re-interpolated in time at an exact 15 min UTC
  2. All pixels where sun elevation is below 2 degrees are interpolated
  3. Altitude correction (using SRTM Altitude database)
  4. Kc-max correction
  5. Bias correction

1. Each pixel is re-interpolated in time at an exact 15 min UTC

To be able to apply the re-interpolation, this step implies to already have the next slot. Let's take as example Germany maps today at 10:15.

HC15mapGHI creates a new map [server]/germany/germany_irr_1504221000.tif. It contains GHI irradiation extracted from the sole 1504221000 MSG slot, i.e. irradiation at approximately 10:11 UT for Germany.

Hc3v5-15mapGHI generates 2 maps:

  • [server]/germany-hc3v5/germany_irr_1504221000.tif contains GHI irradiation from 09:45 to 10:00 UT. This map is final.
  • [server]/germany-hc3v5/germany_irr_1504221015.tif contains GHI irradiation from 10:00 to 10:15 UT. This map is a 4 minutes forecast (for Germany) and will be updated 15 minutes later.

2. All pixels where sun elevation is below 2 degrees are interpolated

When the sun elevation is below 2 degrees, the previous service without post-processing layers (HC15mapGHI) was generating no data (pixel = 254). In the new service HC3v5-15mapGHI, the irradiation values are interpolated using an interpolation based on the persistance of the clearness index Kc (GHI/GHI_clearsky.

NB: this interpolation is also used for every missing MSG images.

3. 4. 5. Altitude, Kc_max and bias corrections

Altitude correction and Kc-max correction are bug fixes for altitude and albedo errors.

Bias correction is a global calibration of hc3v5 w.r.t. BSRN stations.