Daylighting information throughout Europe using the SATEL-LIGHT and SODA internet servers

The Satel-Light Internet server provides to designers and engineers daylight information which was previously unavailable. It is based on a database of daylight and solar radiation, covering Western and Central Europe, which was produced as part of a European project called SATELLIGHT. This database has been computed from the images produced by the Meteosat satellite. Thus it has an excellent spatial resolution (every 5 km on average) and an excellent temporal resolution (every 30 mn). Through a user-friendly interface, the server provides maps, data files and statistics, which can be used to evaluate the daylight potential of any site in Europe. It produces half hourly values of illuminances (horizontal or sloped) but also sky luminances in 13 zones of the sky vault. For a set of case studies, Satel-Light combines these luminances with "directional daylight factors" to produce indoor illuminance information. Thanks to a European project called SODA, the Satel-Light database will be extended to a total of 5 years (1996 to 2000). The aim of SODA is to expand and federate various solar radiation databases available on the Internet, through a centralized access and application services. One of these services is dedicated to daylighting. It allows to describe interactively a room and its fenestration system, and for any site in Europe, to evaluate the potential of daylight inside that room.