Power loss caused by the dust deposition on photovoltaic (PV) modules (also defined as soiling) introduces a challenge for the economic viability of PV deployment in many of the sun-belt countries, including India. Anti-soiling coatings (AS-coatings) are nano or microlayer coating, which reduces dust settlement on PV modules. AS-coatings are designed to be economical and easy to maintain. It keeps the cover glass clean while requiring less water, less energy and less labour to clean and maintain the PV modules. As the AS-coating is deposited on the outer surface of the PV module, it has to withstand harsh climatic conditions, which makes the durability of these coating a crucial factor. Lot of work is done on the development of anti-soiling coatings, which have made their way to the commercial market. However, there is a lack of data and knowledge on how effective anti - soiling coating is as a dust mitigation strategy, and what is the life of AS-coating under field exposure.

We, at NCPRE, are developing a standard test protocol for the evaluation of anti-soiling coatings, which will act as a baseline for testing the coatings available in the commercial market and will also direct us to develop durable anti-soiling coatings (designed to withstand Indian climatic conditions). By conducting multiple field exposure and accelerated stress tests, we have identified that rain, UV exposure, frequent cleaning runs, and a combination of UV exposure and condensation significantly affect the life of anti-soiling coatings during field exposure.

To know more about this topic, please refer to the following papers:

anilkg@ee.iitb.ac.in
mallick@iitb.ac.in
naren@ee.iitb.ac.in