Solar Panel & Skylight Cleaning

Solar panels lose efficiency when covered with pollen, dust, bird droppings, or algae. Oregon's wet climate means panels stay damp enough for algae growth, and spring pollen coats everything. Most manufacturers recommend cleaning panels annually to maintain optimal output, and some warranties require it.

We use deionized water fed through soft-bristle brushes on extension poles. Deionized water doesn't leave mineral spots when it dries, so panels dry streak-free. The brushes are soft enough not to scratch the glass but firm enough to remove stuck-on debris. We don't use soap or chemicals unless absolutely necessary — most buildup comes off with water and brushing.

“Solar panels lose efficiency when covered with pollen, dust, bird droppings, or algae — Oregon's wet climate means panels stay damp enough for algae growth.”

Roof-mounted panels are cleaned from the roof edge or from ladders. We don't walk on the panels themselves. Ground-mounted arrays are easier to access and take less time. Arrays with significant bird droppings or algae growth may need a second pass.

Cleaning restores 5-15% energy production depending on how dirty the panels were. The difference is most noticeable in summer when production peaks. We recommend cleaning once a year in spring after pollen season, or twice a year if you have heavy bird activity or live near agricultural dust sources.

AWP Exterior Cleaning handles solar panel and skylight cleaning across Oregon and Western Washington. Properties in both states deal with similar issues — pollen buildup, bird droppings, and algae growth from constant moisture. Coastal properties in Western Washington see heavier salt deposits on panels, while valley properties in Oregon deal with more tree pollen and organic buildup.

Typical residential solar cleaning costs $150-$300 depending on array size and accessibility. Commercial arrays are quoted per panel or per kilowatt of capacity after a site visit. If your panels haven't been cleaned in over a year, expect heavier buildup and longer cleaning time.