Solar radiation attenuation by aerosol: application to solar farms

Solar radiation attenuation by aerosol: application to solar farms:

Abstract

The use of solar energy requires precise insolation knowledge of the considered site. Solar irradiance depends on geographical and astronomical parameters and variable characteristics of the atmosphere such as aerosol or cloud charge, which has a very important attenuation and pollution role. This study presents the estimate of the annual insolation of sites close to several solar farms. Insolation is calculated from Iqbal’s basic formulas with introduction of the total optical thickness determined by the AERONET. The PSDs and aerosol loading on an atmospheric column allowed the establishment of the attenuation-aerosol concentration relationship. The cloudless atmosphere attenuates the incident solar flux by an annual average of the order of 23.5%, where in average, about 13.73% is attributed to the aerosol, 17.75% for solar farm sites near the Sahara, and 8% for California and Arizona US sites.