This year has seen a record number of telephone calls from clients concerned about the dirt accumulation on their solar panels, specifically from lichen accumulations!
Many of these systems have been neglected for years, by the so called 'self-cleaning technology' and 'no maintenance needed' implied at the time of installation. What the owner or client is now seeing is a drop in output and performance. This is often caused by a severe build-up of lichen growth on their pv.
Lichen not only looks unsightly on a solar panel, but it can also cause permanent module staining, much like bird droppings that have been left for a long time on the panel. Once the physical dirt is removed (if possible) the panels can suffer from staining that is impossible to remove without replacing the entire panel. This staining is known to cause permanent module shading which in turn decreases the lifetime of the panel along with its output and performance.
Lichen can take a minimum of three to four times longer to clean off a solar panel. Ultimately costing the owner more financially and the solar panel cleaner in their time. This could all be avoided by undertaking a regular solar panel cleaning schedule that is specific to the environment in which the solar pv system is situated.