Energy-based Soiling Loss Monitoring Approach for Solar PV System

The energy loss caused by dust and other particles accumulating on photovoltaic (PV) modules has become one of the most important issues for PV system owners. A site-specific and dedicated soiling monitoring system may be necessary to improve yearly energy estimations and optimize cleaning schedules. Commercially available electrical soiling measurement kits compare the short circuit current (I
SC
) or maximum power (Pmax) of clean and naturally soiled PV modules for a specific time interval and irradiation level. In this paper, we present an energy based soiling loss monitoring approach. The I
SC
and P
max
based methods are benchmarked to the energy-based method for soiling data collected from a test station in Mumbai. It is found that the I
SC
and P
max
based methods underestimate the soiling losses by about 2.5-3%.