Rain does not remove bird droppings.

For routine dust, often not, and you can find plenty of people online saying so. The most-cited study behind that verdict came out of UC San Diego, whose researchers said plainly that most homeowners won't get their money back for hiring someone to wash rooftop panels. We think they were right. Two things are worth knowing before you apply that to your roof. First, the study was run on 2010 data, and in December 2022 the CPUC adopted the Net Billing Tariff, NEM 3.0, effective 15 April 2023, which cut what your exported power is worth by roughly three quarters. What a kilowatt-hour is worth to you now depends on how much of it you use yourself, so the old average doesn't decide it any more. Second, none of that arithmetic was about droppings, sap or ash, which don't rinse off and don't recover on their own. If your panels are just dusty, rinse them yourself. Call us for the things a hose can't fix.

Ask any vendor, including us, three questions. Can you reach the centre of the array, or only the edges you can get a pole to? What is left on the glass after the water dries? And does any step of the job, including setup and spotting, require somebody on the roof? Those three answers separate the methods far better than a price per panel does.

We'd rather set the interval after we've looked at your array than sell you a schedule before we have. It depends on what's actually landing on it. Sites near freeways, farmland, construction, flight paths or a lot of trees soil faster, and low-tilt commercial arrays hold soiling that steeper residential roofs shed. Nesting birds change the answer more than anything else on the list.

We won't tell you what your specific warranty says. That's between you and your manufacturer. What we can tell you is that non-contact washing with purified water is the least invasive method available: nothing abrasive touches the glass and nobody stands on the modules. Send us your manufacturer's cleaning requirements and we'll work to them.

Not for the estimate. We assess from the air. For the cleaning itself we work from the ground and from altitude rather than on your roof, so there's no staging, no lift and no crew crossing your property. Your system stays energized and running throughout. There's nothing to shut down and nothing for your team to coordinate on the day.

Deionized water. Because the minerals are stripped out, it lifts soiling and then dries without leaving the spotting or film that tap water and detergents leave behind. No soaps, no chemicals, no residue for the next rain to streak across your array.

By site. Array size, layout, height, access, how heavily it's soiled and how often you want it done all move the number, so we quote each property individually rather than publishing a per-panel rate that would be wrong for most buildings. Recurring schedules and multi-site portfolios price better per clean than one-off calls.

Yes. Our pilots are FAA Part 107 certified and we're fully insured for residential and commercial work. We'll provide certificates and any documentation your property manager or risk team needs before we fly.