Global solar radiation estimation by Iranna-Bapat´s models for India

Estimation of solar radiation is considered as the most important parameter for the design and development of various solar energy systems. But, the availability of the required data is very scarce and often not readily accessible. The foremost objective of the present study was to estimate the monthly average global solar radiation (GSR) at various locations for India, by the generalized Iranna-Bapat´s model. Iranna-Bapat´s model is developed to estimate the value of global solar radiation at any location on earth surface. This model uses the most commonly measurable meteorological parameters such as ambient temperature, humidity, wind-speed, moisture for a given location. A total of 57 locations spread across India are used to validate this model. The computed values from Iranna-Bapat´s model are compared with the measured values. Iranna-Bapat´s model demonstrated acceptable results, and statistically displayed lower RMSE (<;10%) for many locations. Therefore this model could be a good estimator for predicting the global solar radiation at other locations for India, where such data is not available.