Application of dust mitigation strategies to single‐axis‐tracking photovoltaic modules in the semi‐arid areas of South Africa

Abstract

Field generated data for single-axis-tracker (SAT) photovoltaic (PV) modules, subjected to the semi-arid Northern Cape region of South Africa, is presented. Experimental dust mitigation methods and the effects of dust soiling on PV module performance are explored. In particular, the use of a hydrophobic anti-soiling coating and a unique SAT self-cleaning manoeuvre was investigated. The SAT results are further compared to six coated and uncoated stationary PV modules. For the performance comparisons, maximum PV module power output was determined from current-voltage (I–V) curves extracted from each individual PV module. This work further presents a novel I–V curve fitting algorithm, which improves measured I–V curve data resolution for precise maximum power point extraction. The PV module performance comparisons were executed with a performance ratio metric, which is defined as the irradiance and temperature corrected performance factor of a PV module. Contrary to the initial research hypothesis, the hydrophobic anti-soiling coating was found to promote dust soiling. The SAT self-cleaning manoeuvre further delivered unique insights regarding the effects of dew water on dust soiling and displacement. Finally, also unique to the research presented here, is the formal description of infield observations made regarding dust deposition.