Estimation of Solar Radiation using Modified Lagrangian Box Model (MLBM)

Abstract

This study is in validating a novel solar radiation predictor model; namely, Modified Lagrangian Box Model (MLBM) by comparing its performance with global horizontal irradiance values obtained from Campbell Meteorological Station at University of Abuja. The model seeks to reduce computational complexities associated with solar radiation model which pose difficulties for ordinary household user. The MLBM estimates solar irradiance by modifying the extraterrestrial radiation normal beam with solar altitude angles. A statistical analysis comprising coefficient of residual mass (CRM), root mean squared error (RMSE), coefficient of determination (R^2) and relative percentage error (e) were used in validating the model. These performance indicators show that the model has over 80 % accuracy in predicting global horizontal irradiance (GHI) of a landscape at a local scale level.