Do I need to clean my solar panels? Usually not — here's when you might

Answer-first page — the first paragraph is the whole answer, checked reviewed 2026-08-08

Usually no: rain handles most of what lands on a tilted roof array, and studies of typical residential systems find the dirt-related loss is generally small (often single-digit percent) — smaller than the savings you'd throw away on $200–400 cleanings every year. The exceptions are real, though: flat or low-tilt arrays, heavy construction dust, pollen seasons with no rain for weeks, and the occasional bird-roost corner.

When cleaning is actually worth it

Measure before you pay: check the production chart in your inverter's app for a sudden drop across a whole array — that points at soiling, not equipment. If a specific corner is covered (birds, leaves), rinse it. If a whole array is flat or dusty in a no-rain climate, a cleaning every year or two is cheap insurance. The common trap is the opposite: paying for a clean when the loss is 2%.

Do not climb up there yourself on a steep roof — the injury risk dwarfs the production gain. And watch the warranty: pressure washing and some detergents can void panel coverage. Water and a soft brush from the ground, or a professional with fall protection, is the entire toolkit.

Questions homeowners ask

Will a cleaning company damage my panels?
It can: pressure washing can crack glass or force water past seals; harsh detergents void warranties. Ask what they use, and get their damage/fall-protection insurance in writing.
Do panels need cleaning before they're inspected?
No — a soiling loss of a few percent rarely changes a performance assessment. The production numbers in your app are the evidence, not a spotless finish.