Press Review

PV Magazine – January 17, 2023

A new report by the International Energy Agency’s Photovoltaic Power Systems Programme (IEA-PVPS) estimates that lost revenue from PV module soiling amounts to more than €3 billion ($3.2 billion) per year – a figure that is only set to increase as PV systems grow larger and more efficient.

Soiling – where PV modules become coated with dust, dirt, sand, or snow and thus receive less sunlight – is still an underestimated problem for solar power systems. Specialized solutions are now available in the form of anti-soiling glass coatings, automated and manual cleaning products, and models to predict the ways to use them most economically. But our understanding of the issue is still evolving, particularly as PV systems move into new regions with different environmental conditions, and the technology continues to change and improve.

A new report by IEA-PVPS Task 13 seeks to push the understanding of soiling a step further, taking a detailed look at the mechanisms causing soiling right down to the size and shape of the individual particles that build up on module’s surface, and the surrounding conditions that lessen or worsen its impacts.

The report estimates that in 2018, soiling caused at least a 3% to 4% loss to global annual energy production from PV – amounting to lost revenue of €3-5 billion. And this is expected to increase to around 4% to 5%, and €4 billion to €7 billion this year, thanks to an increase in PV installations in regions highly prone to soiling, economic pressures, and the fact that more efficient PV modules will suffer more considerable losses to their output due to soiling.