Assessment of the erosion risk of sandstorms on solar energy technology at two sites in Morocco

Kurzfassung

This multi-disciplinary research paper should help solar power plant developers to perform an advanced site assessment in arid locations where the annual irradiance levels are high, but significant quantities of airborne sand and dust increase the risk of optical energy losses due to extinction, soiling, erosion damage (also known as abrasion), etc. Due to these effects sandstorms have a direct consequence on the operation and maintenance (O& M) costs. The work presented in the following characterizes airborne sand and dust material and later focuses on the resulting erosion effects. Some important meteorological and geological parameters for sandstorm occurrence and the resulting erosive damage on glass materials by impacting windblown material are extracted from literature. The respective parameters have been measured at two locations in Morocco (Zagora and Missour). After evaluation of wind and humidity data and a comprehensive soil analysis, the erosion risk was estimated to be higher in Zagora. The specular reflectance loss of exposed silvered-glass reflectors of 5.9% in Zagora and 0.8% in Missour after 25 months of exposure verified this estimation. Additionally, a specular reflectance analysis on a mirror sample that has been exposed for nine months in Kuwait is shown. On that sample specular reflectance losses of more than 40% were measured. A checklist with seven items is given in the conclusion to help solar plant developers to evaluate the risk of component aging due to sand storm erosion.