Impact of Cleaning cycle on Soiling losses !!!
The power output from a solar plant is directly proportional to the solar radiation it receives on its surface. However, there are various factors which affects the amount of solar irradiance the solar panels receive. One major factor which affects the solar irradiance to reach to the solar cells is the accumulation of dirt known as soiling losses. Typically, the soiling losses in a solar plant are considered about 2 -3% while designing the plant and estimating the energy yield. However, in actual conditions the losses due to soiling the deposition of the solar panels are observed to be 10 to 12%.
Most of the solar plants adopt or bi-weekly cleaning cycle for maintaining their energy yield however the approach of bi-weekly cleaning leads to dust deposition and the power output in case of bi-weekly cleaning is reduced close to 10% of soiling losses which is a major factor of revenue loss to the solar plants.
We have done some analysis in one of our solar rooftop projects of 500 KWp located in Guwahati where the tilt angle is about 10° and the losses by adopting bi-weekly cleaning cycle or of the order of 15% and when we increase the cleaning cycle on weekly basis, the loss is reduced close to 5%. It is important to find an optimum cleaning cycle wherein you are cleaning cost of solar modules is lesser than the energy yield revenue.
Average generation for weekly cleaning cycle is 6.78% more then biweekly cycle and for total generation also increase 7.98%.
In terms of revenue, weekly cleaning cycle is giving 7.98 % more revenue compare to biweekly cleaning cycle. This analysis is only for 500 kWp plant.