Solar · Maintenance
How do I clean solar panels safely without damaging them?
Short answer
Clean from the ground with a soft long-handled brush and clean water or a mild biodegradable soap, on a cool day, and never stand on panels or use a pressure washer. If panels can only be reached from a ladder or roof, use a professional with working-at-height cover. Stop and report any damaged cabling.
Last checked 24 September 2026 · 2 sources
In more detail
- EST: turn the system off first per the manual; look for damaged cabling and stop if you find any (shock hazard).
- Avoid washing-up liquid (film attracts dust; harsh chemicals can affect coatings) and abrasive pads; avoid high-pressure washers (can damage seals and wiring).
- Clean in cool weather; water evaporating from hot glass leaves streaks. Do not spray cold water on very hot glass.
- Do not walk on panels: they are not designed to take a person's weight and cells can micro-crack invisibly.
- Check the module manufacturer's installation/maintenance manual: warranties (e.g. JA Solar s3.4) exclude modules not serviced according to the manual.
- Hard water can leave mineral spots; deionised/purified water-fed poles are the professional norm.
The facts, dated
- 01EST advises against pressure washers and standing on panels
installer_view · UK · checked 24 September 2026 · Energy Saving Trust
- 02JA Solar warranty excludes modules installed, used and serviced not in strict compliance with its installation and maintenance manual — s3.4
manufacturer · n/a · checked 24 September 2026 · samonolithportalprodcdn.blob.core.windows.net
What we saw in the field
Adds to installer field evidence: installers mention cleaning but not the warranty link to the manufacturer's cleaning method.
Sources
- Energy Saving Trust — energysavingtrust.org.uk/solar-panel-cleaning-maintenance/
- samonolithportalprodcdn.blob.core.windows.net — samonolithportalprodcdn.blob.core.windows.net/assets/general_product_documents/1…
Last checked: 24 September 2026