A Comparative Study of Some Regression Models to Estimate the Global Solar Radiation on a Horizontal Surface from Sunshine Duration and Meteorological Parameters for Ghardaïa Site, Algeria

Abstract

A comparison between some regression correlations for predicting the global solar radiation received on a horizontal plane has been processed. Seven models for estimating the global solar radiation from sunshine duration and two meteorological parameters (air temperature and relative humidity) are presented. The root mean square error (RMSE), mean bias error (MBE), correlation coefficient (CC), and percentage error (e) have been also computed to test the accuracy of the proposed models. Comparisons between the measured and the calculated values have been made. The results obtained show that the linear and quadratic models are the most suitable for estimating the global solar radiation from sunshine duration, and for the models based on meteorological parameters, Abdalla and Ojosu's models give the best performance with a CC of 0.898 and 0.892, respectively.

Empirical Validation of Regression Models for forecasting Global Solar Irradiance: A Case Study of Abeokuta, Nigeria

“…ii. Solar radiation incident outside the earth's atmosphere called extraterrestrial radiation, calculated using the following equation (Gairaa and Bakelli, 2013):…”

“…This model, developed in 1940 by Prescott, has been widely used and described by various authors in the study of global solar radiation. Its variations as given by Gairaa and Bakelli, (2013), are as shown below:…”

“…This model was first used by Hargreaves et al 1985 to estimate the global solar radiation by using the difference between the daily maximum and minimum air temperature and extra-terrestrial radiation (Gairaa and Bakelli, 2013). This model is represented below:…”

“…The Garcia model is a slight modification of the Angstrom-Prescott model. Equations for its variations are given below (Gairaa and Bakelli, 2013):…”

Prediction of monthly average global solar radiation based on statistical distribution of clearness index

“…The proposed approach in this work was compared with the established regression models: Angstrom-Prescott Model [30], Garcial Model demonstrated [31] and Hargreaves-Sammani model [32]. These models are the popular models in which the author(s) compared their new proposed models with others [33].…”