Abstract

Because of the massive increment in solar plants located in extreme environments, studying the association of climate parameters and soiling in natural conditions has been necessary. In this work, solar glass coupons were exposed to environmental conditions in Salvador solar plant, in the Atacama Desert, during summer and winter campaigns. The soiling was quantified and characterized, and the degradation of optical properties of soiled coupons was also measured. Regarding the reduction of the optical properties of the glass coupons, it was observed that the detrimental effect was higher in summer than in winter. A statical analysis found that this difference in soiling performance is related to the relative humidity and wind speed present in each campaign, mainly due to the daily variations of these parameters. Prolonged periods of relative humidity close to 30% promote the adhesion of particles to the PV glass surface and inhibit their resuspension by the action of the wind, i.e., more dust mass accumulates. Since the effect of soiling is more critical during the summer period, the use of a preventing soiling mitigation system is highly encouraged, and the adjustment of the cleaning schedule according to the seasonality of soiling.