Comparison of different models for estimation of diffuse solar radiation in Jharkhand (India) region

The main objective of this paper is to estimate the monthly average diffuse solar radiation for the Jharkhand region (India). The measured data for the region is not available; in this paper the monthly average of solar radiation is calculated. Estimated values of diffuse radiation to total solar radiation using different correlation equations developed by Kreith, Gupta, Liu and Jordan and Page are presented. These models are then compared by estimating diffuse irradiation values for different locations over Jharkhand. As the Kreith model is most suitable for diffuse solar radiation in India, taking it as the base model the percentage error is calculated for all the other models.