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Home  >  Tools  >  Sun Position


Sun Position

Sun_position_algorithms  is a C++ header file which contains five algorithms for computing the sun position.

Input parameters required for the computation are:
- time (UT hour, day, month, year, difference TT-UT);
- geographic coordinates (latitude and longitude);
- pressure;
- temperature.
The last two parameters are used to compute the correction due to the atmospheric refraction.

The accuracy depends on the chosen algorithm: the most accurate one has a maximum error lower than 0.003°.

You can  download  the C++ header file containing the algorithms. The file  (Sun_position_algorithms.h)  is given with a short introduction  (Sun_position_intro.pdf),  where the algorithms are described and the use of the functions defined in the header file is illustrated. The material can be freely disseminated.

A more technical description of the algorithms can be found in:
R. Grena, Five new algorithms for the computation of sun position from 2010 to 2110, Solar Energy, vol. 86 (2012), pages 1323-1337.
(This paper should be cited if the algorithms are used in published scientific work).

Author: Roberto Grena, ENEA UTRINN-PCI.

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