Presentation Description: The accumulation of dust and other contaminants on PV modules, known as soiling, is one of the principal energy loss factors in PV systems. However, prediction of soiling losses at a given location is difficult, and therefore losses must be directly measured to inform cleaning decisions. While there are many types of soiling measurement devices in the PV industry, most soiling measurement sensors perform indirect measurements and do not measure actual PV module power losses due to soiling. In this presentation, we demonstrate how the non-uniform accumulation of soiling particles on PV modules can lead to power losses significantly in excess of the total average dust coverage, and we highlight strategies for efficiently measuring actual PV module power losses due to soiling. In addition, we demonstrate how soiling power loss methodologies need to be updated for bifacial PV systems, which have the potential for both front and rear side soiling as well as variable total front plus rear resource.
Learning Objectives:
Understand how soiling distribution patterns on PV modules affects power losses
Determine how to measure power losses due to soiling
