Estimation of Daily Diffuse Solar Radiation for Different Iraqi Cities

Abstract

Solar radiation energy is a very attraction issue for study because it is renewable and clean energy. Analysis of 22 year of daily solar radiation (global and diffuse) on horizontal surfaces at different cities in Iraq . To achieve this goal , a special statistical model was used to estimate diffuse fraction from clearness index at a daily scale at different Iraqi regions. The results showed that this model can estimate diffuse solar radiation on a horizontal surface with high resolution. It also showed a good correlation between the model and observation.Keywords; diffuse fraction, solar energy, solar radiation, diffuse radiation.