Estimation of solar radiation on the ground from Meteosat satellite images and different models: Case of Ghardaïa Region
Résumé
Several processes govern the propagation of radiation through the Earth's atmosphere from space and reaching the ground. Radiative disturbances and their monitoring are then essential to know for various applications (optical communications, solar energy system, climatic studies, etc.). They can be tracked using active instruments (radar or lidar) or both ground-based solar radiation measurements when available and clear-sky models. This article deals with the estimation of solar radiation at the Earth's surface from geostationary satellite images. An innovative method is developed for this, effective even in the absence of ground measurements. Six clear-sky models including ESRA2 and one year of satellite data (2015) are used to carry out the study. The results are then compared with those measured on the ground during the same period at Ghardaïa (Algeria). They reveal the effectiveness of the method for estimating global solar radiation at the ground when using the model ESRA2. Indeed, an rmse of 670.3 Wh/m2, a mape of 10.41% and an mbe of 214.96 Wh/m2 and a correlation coefficient R of 0.93 were obtained with ESAR2 using MSG-3 images taken in the visible channel 0.6 µm. This result is confirmed with the images of the near-infrared channel 0.8 µm. A previous study based solely on ground data had also retained the ESRA2 model for Tamanrasset.