We are doing science for policy
The Joint Research Centre (JRC) is the European Commission's science and knowledge service which employs scientists to carry out research in order to provide independent scientific advice and support to EU policy.
There exist many online sources of solar radiation data and several free PV estimation tools. Here we have collected links to a few of them. If you think there are important data sources missing in this list, please contact us.
These data sets generally consist of "maps" of solar radiation over large areas, mostly calculated from satellite data. Most of these data are derived from geostationary satellite images with a resolution of a few km and time resolution that can be as high as 15 minutes. This means that the amount of data can be very large, and specialized tools are needed to read and convert the data.
Slope The Climate Monitoring Satellite Application Facility (CM SAF) is a collaboration between a number of European Meteorological Services to use EUMETSAT satellite data to produce a large number of climatic data sets. These include several different solar radiation data sets (global and direct) with varying time resolution (from hourly to monthly) and for different geographical areas. Using the web user interface it is possible to order data for different time intervals and for a user-defined region.
PVGIS uses CM SAF data extensively, and the PVGIS team has contributed solar radiation data to CM SAF.
Slope The Land Surface Analysis Satellite Application Facility (LSA SAF) is another of EUMETSAT's Satellite Application Facilities that provides spatial solar radiation data sets with high time resolution, in this case using the Meteosat Second Generation satellites which cover Europe and Africa.
The National Solar Radiation Database (NSRDB) is a spatial solar radiation data set developed by the National Renewable Energy Laboratory. The data set provides half-hourly values of solar irradiance (global, diffuse and direct) from satellite using data from the GOES geostationary satellites. The data cover land surfaces in most of the Americas and in the Pacific.
PVGIS uses data from NSRDB to calculate PV energy yield and solar radiation values for the Americas.
These data sources mostly provide time-resolved solar radiation data for a single location at a time, either through a web site or via a web service (much like PVGIS).
Slope The Copernicus Atmosphere Monitoring Service (CAMS) combines atmospheric modeling on aerosols, water vapour and ozone with satellite-based observations of clouds. The time series solar radiation service for both all-sky and clear-sky irradiation is jointly provided by DLR, Armines, and Transvalor. A verbose mode provides all atmospheric variables being used. The CAMS Radiation Service is the operational follow-on activity of previous Monitoring Atmospheric Composition and Climate (MACC) project activities.