How often should solar panels be cleaned to remove lichen?

If you've got solar panels anywhere around Chippenham, Calne or the surrounding villages, you'll know how easily they get overlooked once they're up on the roof. Most people only think about them when the electricity bill looks a bit higher than expected — and by then, lichen has often had months, sometimes years, to take hold.

Why lichen is different from ordinary panel grime

Dust and general grime wash off panels fairly easily and don't do much harm sitting there for a few months. Lichen is a different problem. It anchors itself to the glass and spreads slowly outward in pale, crusty patches, and unlike dust, it doesn't rinse away with a hose or shift in the rain. Left alone, it gradually shades out more and more of each cell, and a panel that looks "a bit spotty" can be losing meaningful output without anyone noticing, because the drop happens gradually rather than all at once.

How I remove it

Lichen removal isn't something a standard clean covers — it needs a specialised treatment to lift it fully without damaging the glass or the panel surface. I use this only where lichen has actually taken hold, working across each panel until it's back to bare glass. It's slower, more careful work than a routine dust-and-dirt clean, which is why it's priced separately.

Keeping panels clear afterwards

Once panels are back to clean glass, they're far

easier to keep that way. I offer two simple options depending on the property and how quickly panels tend to dirty up again locally:

• A dust-and-dirt clean every six months

• A single clean once a year

Both are enough to stop grime building into something more stubborn like lichen in the first place. My water pump is solar-powered, so keeping panels clear doesn't come at any extra environmental cost either.

Worth checking now

If your panels haven't been looked at in a while, it's worth a glance next time you're up a ladder doing gutters, or just looking from a neighbour's upstairs window. Pale or orange-ish speckling that doesn't wash off in the rain is usually the first sign.

I cover Chippenham, Calne, Malmesbury, Tetbury, Batheaston, Bathford and the villages between. If you'd like an idea of what your panels need, send me a photo and I'll get back to you with a straightforward quote.