Analysis of Soiling Losses for Different Cleaning Cycles

A methodology to analyse the annual energy losses due to soiling of solar PV modules is developed. It is based on the actual soiling rates observed in Mumbai over a 5 year period, andalso on PV system simulations using PVSyst. The impact of different cleaning cycles is also investigated. The impact of module performance degradation on the energy output is also investigated. The developed methodology is applied to a single string system over a 11 year period from 2000 to 2010. It is found that the long term degradation would be the dominant loss process for reasonable cleaning frequencies of once in 42 days. This methodology can be applied to other locations, provided the locations have predictable weather patterns.