Soiling can be a significant loss factor for solar energy systems as dust or dirt-particles may significantly reduce the output by 15% to 30%. Soiling is the process where dirt, dust, and other contaminants deposit on the photovoltaic panels ultimately impeding the transmission of light into the panel. Hence many solar panel manufacturers are researching the potential benefits of incorporating anti-soiling properties into solar panel coatings.
Dirty solar panel tend to cause loss in energy production, depending upon weather conditions and localized terrain. There are many countries where solar projects are facing common environmental conditions such as –
- Wind speed/direction
There are many ways of cleaning such solar panel, with air, water or even mechanically. But these are not long-term solutions and would cost the owners of the project a lot, particularly those in arid regions.
The most accurate solution to this issue is an anti-soiling coating, as it reduces the soiling rate by preventing dust/sand from entering the panel using wind and gravity. It also reduces the cost of cleaning by increasing the breaks between cleaning cycles. The anti-soiling coating is based on technology which maximizes the panel output. Also, the coating is designed to add anti-soiling functionality without undermining any other properties.
The major benefits of an anti-soiling coating are-
- Significantly better output than uncoated glass reducing transmission loss
- Excellent anti-reflective properties: average transmission gain is ~3%
- Strong performance in various durability tests
- Easier and faster cleaning
- Lower residual soiling level after cleaning
- Excellent UV resistance, essential in areas with high sun loads
The Dry Run
A set of solar panels with anti-soiling coating were tested and some of the major things to remember were –
- The coating is 100% inorganic which gives it an excellent UV-resistance in arid regions
- Accelerated cleaning tests were executed by 2 leading robotic cleaning equipment vendors. The optical properties showed no significant change
- The average additional DC output is 4.3% vs uncoated panels, clearing showing anti-soiling coating consistently outperforms the uncoated panels
Soiling is a persistent issue for solar panels. In an effort to address this issue Vikram Solar has come up anti-soiling coating allowing the panels to reduce transmission loss and increases the output making the cost of cleaning a little less heavy on the pocket for the owners of the project.