“…On the other hand, the determination of solar energy capacity e!ectively through the empirical models plays a key role in developing solar energy technologies and the sustainability of natural resources (Ertekin and Yaldiz, 2000). For this purpose, in the past, several empirical formulas using various parameters have been tested in order to estimate the solar radiation around the world (Bennett, 1965;Sharma and Pal, 1965;Swartman and Ogundale, 1967;Reddy, 1971;Munroe, 1980;Barra, 1983;Hutchinson et al, 1984;Ma and Iqbal, 1984;Badescu, 1987;Bahel et al, 1987;Soler, 1988;Samuel, 1991;Kudish and Lanetz, 1992;El Aroudam et al, 1992;Nfaoui and Buret, 1993;Srivasta et al, 1993;Rehman and Halawani, 1997;Aksakal and Sha"q-ur-rehman, 1999;Mosalam Shaltout et al, 2001;Hassan, 2001). These parameters include extraterrestrial radiation, sunshine hours, relative humidity, ambient temperature, soil temperature, number of rainy days, altitude, latitude and cloudiness.…”