SOILING ANALYSES AT PVUSA

摘要

Nearly all who have visited PVUSA's Davis, California site, especially those who visit during the dry summer months, have asked how much of the potential generation from a typical photovoltaic (PV) array is lost due to dust. Our customary response has been "about 1% to 4% per year," but this is based on studies done by others. We have long suspected the losses were somewhat greater at Davis. A simple test station was installed on a south-facing fixed 18° tilt roof mockup at PVUSA in 1998 to quantify the impact of soiling. 1999 was a drier than normal year and the annual soiling losses were 7%. 1998 was a substantially wetter than normal El Nino year and the annual soiling losses were 4%. This paper describes the test setup, presents results from the first two years of the ongoing evaluations, and discusses their relevance to PV system generation at other locales and orientations.