First conference on measurement and modeling of solar radiation and daylight “Challenges for the 21st Century” Napier University, Edinburgh, 15-16 September 2003

This was the opening paper to the Conference. The paper combines the historic experience of the author on solar radiation climatology built up over the last 50 years with a more detailed account of his contribution to a number of recent European funded projects dealing with solar radiation in the context of applications. These projects have been especially concerned with the improved delivery of accurately estimated and reliable solar radiation data to users. The recent European projects have made extensive use of satellite data in conjunction with reliable ground truth sites. The paper explains the special emphasis now being placed on the effective use of IT to provide user selected data delivery on the world wide web. The paper finishes with a suggested road map for the future for solar radiation and daylight measurement and applications research. The importance of achieving an improved understanding of diffuse radiation through improved measurement approaches is especially stressed. The need for an improved understanding of spectral radiation is also underlined.