What makes panels dirty
Panels sit at an angle so rain can run off, and light dust does wash away. The problems are deposits that stick. Bird droppings dry hard and block light in patches. A thin film of grime builds up gradually, so the change is easy to miss from the ground.
In Kent several local conditions add to this. Homes near the coast collect salt film carried on the wind. Properties beside arable land get dust during ploughing and harvest. Roofs under trees catch sap, pollen and leaf litter, and the lower edge of a panel can start to grow lichen where water and dirt collect.
- Bird droppings
- Coastal salt film
- Dust from nearby farmland
- Lichen along the lower frame edge
- Pollen and leaf debris from trees
Signs your panels need attention
The clearest sign is a drop in generation that is not explained by the weather. If your system has an app or a meter, comparing similar sunny days across the year can show a gradual decline. A visual check from the ground or an upstairs window may reveal droppings, a grey film or green edges.
Shallow-angled panels and those on flat commercial roofs tend to show soiling sooner because water runs off slowly and debris settles.
How often should solar panels be cleaned?
There is no single interval that suits every roof. A steep, open roof away from trees and birds may stay reasonably clean for a long time. Panels close to the sea, beside fields or under a gull roost may need cleaning far more often.
A sensible approach is to watch generation and check visually, then clean when there is a visible build-up or an unexplained fall in output. Your installer or the manufacturer's documents may also give guidance, and it is worth following that where it exists.
Why the cleaning method matters
Solar glass has coatings and the frames have seals, so harsh brushes, abrasive pads, detergents and pressure washers should be avoided. Soft brushes and clean water lift the dirt without scratching. Cleaning from the ground with water-fed poles also avoids the risks of climbing onto the roof.
Working on a roof with live electrical equipment is not a job for an untrained homeowner. If you are unsure, it is safer to look from the ground and ask for advice.
What drives the cost of solar panel cleaning
Prices for solar panel cleaning vary with the job, and the main factors are easy to understand once you know what they are. Every quotation is based on the specific roof rather than a fixed rate.
- The number of panels and how they are laid out
- Roof height, pitch and whether panels can be reached from the ground
- How heavy the soiling is, especially droppings and lichen
- Whether roof, moss or gutter work is done on the same visit
- Commercial access arrangements on larger buildings
Booking a clean
OOR External cleans domestic and commercial solar arrays in Kent and can combine the work with roof cleaning or gutter clearance. Send a photograph of the roof and the postcode, or call Jordan on 07860 962107, and you will receive a written quotation.