Review of PV soiling measurement methods

Soiling can greatly decrease the performance of PV systems in desert regions. There are different ways of measuring soiling in the field and laboratory, such as mass of dust deposited, light transmission reduction, or output of a PV cell. A review of common PV soiling measurement techniques is presented. Also, sunlight angle of incidence is shown experimentally to affect the apparent soiling loss of a PV array with high dust load, which may impact comparison of such measurements taken at different times of year.