The purpose of this second meteorological support task was to improve access to solar radiation data, facilitate the estimation of key solar radiation parameters by solar engineers and designers, and to develop a uniform format for the presentation of data for solar insulation and other meteorological data.

Measurements of solar irradiance and its direct beam and diffuse components are important for the design and testing of solar energy systems. However, since meteorological networks are often spaced too far apart to provide the measurement needs for a particular location, models have been developed for estimating the solar irradiance for places where no measurements exist. An overview of existing estimation methods was prepared which catalogues and classifies the models.

Task 5 researchers also compiled the first catalogue of data sources from around the world, their measurement programs, and the format of the available data. Another document contains recommendations for the minimum meteorological network needed to obtain the measurements required for solar energy applications.


  • Compilation of sources of meteorological data
  • Handbook on radiation estimation methods
  • Recommendations on meteorological networks
  • Uniform format for data preparation