Calibration and evaluation of estimation models of global solar radiation for the state of Goiás, Brazil

Despite the importance of global solar radiation (Rs), data this variable are not available for many regions Brazil due to low density surface weather stations, mainly in North and Central-West regions. The estimation with no Rs based on mathematical models, which has shown be a viable alternative. objective work was contribute these studies through calibration evaluation three traditional models: Angstrom-Prescott (AP), Hargreaves (HAR), Bristow-Campbell (BC), and, addition, propose new model (PMo) from multiple regression. models were adjusted evaluated six locations state Goiás (Central-West Brazil), using meteorological 2008 2016. local adjustment process improved predictive capacity AP (r2 = 0.74 MAE 1.68), BC 0.62 2.34) HAR 0.55 2.32). However, according Nash index, unsatisfactory performances found municipalities Mineiros Rio Verde, Verde. requiring more variables, PMo estimated adequately 0.70 1.98), superior performance methods.