PV Soiling Loss Analysis for Two Sites in North Carolina

This study examines the impact of soiling on the performance of photovoltaic (PV) systems at two sites in North Carolina, USA: Boone and Mount Holly. Custom-designed soiling monitoring stations, developed by the Photovoltaic Reliability Lab at Arizona State University, were installed at both locations to record short-circuit current and precipitation data. These measurements were used to calculate the Soiling Loss Factor (SLF), which quantifies the reduction in expected PV output due to soiling accumulation. Results indicate that, even during the driest observed periods, worst-case soiling losses did not exceed 6% and 3% at the Boone and Mount Holly sites, respectively. These findings offer practical guidance for developing cost-effective cleaning strategies, if any.