Do solar panels need cleaning?

Rain washes off most everyday dust, so many panels in the UK need little cleaning. But some homes lose a noticeable amount of power to dirt.

When cleaning is worth it

• Panels are fairly flat, so dirt sits on them rather than washing off.
• You live near farmland, a busy road or the coast.
• Birds roost on the roof, or moss and lichen are growing.
• Your app shows output falling compared with the same month last year.

How panels should be cleaned

• Pure water with a soft brush, usually from the ground with a water-fed pole.
• No pressure washers or harsh chemicals: they can damage the coating and your warranty.
• Early morning or evening, as cold water on hot glass isn't ideal.

How often

Once a year is plenty for most homes. Some people book it alongside a window clean to save on the call-out.

Tip: If birds are nesting under the panels, ask about bird-proofing mesh at the same visit.