Solar energy is one of the most promising renewable energy sources. The availability of the solar energy potential data is very scarce and often not readily accessible. The main objective of this study was to estimate the monthly average global solar radiation at various locations for South America, 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 35 locations spread across the continent 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 values of RMSEs. Therefore this model could be a good estimator for predicting the global solar radiation at other locations for South America, where such data is not available.