Solar Position Algorithm (SPA)

Technology Marketing SummaryThis algorithm calculates the solar zenith and azimuth angles in the period from the year -2000 to 6000, with uncertainties of +/- 0.0003 degrees based on the date, time, and location on Earth. (Reference: Reda, I.; Andreas, A., Solar Position Algorithm for Solar Radiation Applications, Solar Energy. Vol. 76(5), 2004; pp. 577-589).DescriptionThe Solar Position Algorithm consists of an algorithm implemented in C for solar radiation applications which calculates the solar zenith and azimuth angles for the years -2000 to 6000, with uncertainties of +/- 0.0003 degrees.Benefits

• High degree of accuracy

Applications and Industries

• Solar Tracking Device Manufacturing
• Solar Tracking Simulation Software

More InformationTechnology is Copyrighted
See http://www.nrel.gov/midc/spa/Technology Status

Development Stage	Availability	Published	Last Updated
Development - Tested and validated	Available	01/21/2010	02/02/2010