Quality control of global solar radiation using sunshine duration hours

The aim of this study was to develop a new and automatic method for controlling the quality of daily global solar radiation, G(d), using sunshine duration hours. The new method has three levels of tests: first. G(d) is compared against daily extraterrestrial radiation that is received on a horizontal surface (0.03 x G(od) <= G(d) <G(od)); second, G(d) should only exceed by a small amount of the daily clear sky irradiation that is observed under highly transparent clear skies (G(d) < 1.1 G(cd)): and third, the method uses a series of persistence checks that utilize the relation between daily global solar radiation and relative sunshine duration hours. The method is capable of identifying systematic and non-systematic errors and its ability has been shown in three different climates including semi-arid, coastal humid and very and climates. (c) 2008 Elsevier Ltd. All rights reserved.