Establishing New Regression Equations for Obtaining the Diffuse Solar Radiation in Sakarya (Turkey)

Abstract

In this paper diffuse solar radiation component is investigated for Sakarya city (Turkey). For this purpose, 17 diffuse solar radiation equations correlating the diffuse fraction with the clearness index and/or the sunshine fraction are selected from the literature. The predictions obtained from the selected equations are utilized to determine the regression constants of the new equations. In conclusion, the best equation for the city is introduced by performing statistical analysis.

Keywords

• clearness index
• diffuse fraction
• diffuse solar radiation equations
• statistical analysis
• sunshine fraction