HC3 Archives

HelioClim-3 Archives


HelioClim-3 solar radiation database

HelioClim-3 is a satellite-derived solar radiation database. It exploits the Heliosat-2 method to estimates a "cloud index", based on the analysis of the 15 minute Meteosat Second Generation (MSG) satellite images in the visible band.

Our most advanced HC3 version 5 applies then this "cloud index" to a "clearsky model" computed from a precise atmosphere description in terms of water vapor, aerosols and ozone, name McClear (~3 hours and ~40 km resolution, worldwide).

Our database is organized to deliver very fast time series of irradiation, from Feb 1st 2004 up to yesterday.

Data are accessible either using the SoDa web portal or via automatic wget commands.

In addition, 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 (DSM), with a spatial resolution of ~100m.

This service has been evaluated to check the quality of the output data. We compared HelioClim-3 solar radiation values with in-situ measurements from pyranometers: validation results.


HC3 spatial resolution and coverage

Feb. 2004 up to yesterday

Data from 1 min up to 1 month

All radiation components over horizontal, fix-tilted, and any tracker-type planes

HelioClim-3 offers

The data is available on-demand and also through different subscriptions depending on your need:

Standard subscription


Automatic subscription


Automatic subscription per request

The price of our standard annual subscriptions depends on:

  • the number of time series you needs to retrieve every day/month
  • the radiation components (Global Horizontal Irradiation component only or other ones)
  • The time step of retrieval (from 1 min up to 1 month)

All annual subscriptions include an unlimited access to the Web interface, and up to 200 automatic requests per day (or per month depending on your subscription). A price is applied per request beyond 200.


The difference with a standard annual subscription is:

  • Automatic access only
  • the number of automatic requests is limited to 100 per day (or per month depending on your subscription)

The price is 25% off compared to standard subscriptions.


If the number of requests is below 30 per day (or per month for monthly values), we recommend you to opt for an annual subscription per request.

The access to the data is automatic.

Custom subscription depending on the solar data

           Time step

(GHI only)
(all components, horizontal and fix-tilted)
Normal - 2D tracker
(all components, horizontal and normal)
Monthly HCmonth HCmonthIncl HCmonthDNI
Weekly HCweek - -
Daily HCday HCdayIncl HCdayDNI
Hourly HChour HChourIncl HChourDNI
15 min (from 1 to 30 min) HC15 HC15Incl HC15DNI

"HC" stands for HelioClim, then just add the time step and the plane orientation (default: horizontal). Eg.: "HCdayIncl" means "HelioClim3 daily irradiation values over an inclined plane".