Global, direct and diffuse solar-radiation in Syria

Solar-radiation components, namely global, diffuse and direct, were calculated over the Syrian landmass using several mathematical equations starting from the Angstrom formula. An appropriate theoretical method and a computer program were specially designed and developed for these calculations. The program provides fast, direct and accurate information about the global, diffuse and direct solar-radiations on any site in the country. In addition, the applicability, precision and the accuracy of this method has been statistically tested. The relative percentage error between the calculated values and the meteorological data was found to be in the range of +/-3% in the worst case (i.e., for winter time). (C) 2004 Elsevier Ltd. All rights reserved.