Cleaning solar panels: is it worth it, and who should do it?

What a solar panel clean involves

A solar cleaner accesses the roof safely, then washes the panels with purified or deionised water and soft brushes or a water-fed pole, lifting off the dust, pollen, salt and bird droppings that dull the glass. Good operators avoid harsh chemicals and abrasive pads that can damage the panel coating, and many do a quick visual check for obvious cracks, lifted panels or shading while they're up there.

It's purely a cleaning job — the value is in the safe roof access and the right water and gear, not in touching anything electrical. Whether it's worth doing depends on your location: coastal salt, heavy pollen, dust or lots of trees dirty panels fast and make a clean pay for itself, while a clean, rain-washed suburban roof may barely need it.

What a clean costs — and whether it pays

Solar cleaning is priced per job, scaling with the number of panels, the roof height and how dirty they are. A modest single-storey system lands at the low end; a large two-storey array with heavy build-up sits higher. Some cleaners bundle it with a gutter clean or general roof wash, which spreads the access cost across more work.

The honest question is payback. A genuinely filthy array can lose a noticeable slice of output, so a clean recovers real generation; lightly dirty panels that rain keeps mostly clear may not justify the cost every year. Treat the figures here as indicative, weigh the likely output gain against the price, and clean on the dirt, not the calendar.

Choosing a cleaner — and the safety line

Panel cleaning itself isn't a licensed trade, so the things to check are practical: public liability insurance, safe working-at-height practice and the right equipment, because most of the risk here is the roof, not the panels. Ask how they access the roof and whether they use purified water and soft brushes rather than a pressure washer that can force water into the panel seals.

The line to hold is electrical. Cleaning the glass is fine for a competent cleaner; anything involving the wiring, isolators, inverter or the panels' electrical connections is not — that's work for a CEC-accredited solar installer or a licensed electrician. If a cleaner spots a fault, the right move is to flag it for an accredited installer, not to poke at the wiring themselves.

Mistakes to avoid

Most solar-cleaning missteps are either paying for a clean the panels didn't need, or letting the job stray from washing glass into touching electrics it shouldn't.

• Cleaning on a fixed schedule rather than when the panels are actually dirty
• Letting a cleaner near the wiring, isolators or inverter — that's accredited-installer work
• Allowing a high-pressure washer that can force water past the panel seals
• Hiring anyone for roof work without confirming height-safety practice and insurance
• Assuming a clean will fix a drop in output that's actually a fault or shading issue