Your panels are quietly losing a quarter of their output.
Deionized water, zero chemicals, zero residue. We clean rooftop solar across San Francisco and leave nothing behind on the glass — not even a mineral spot.
Same array, same afternoon.
Both photos taken from the ground with a water-fed pole — no one walked on the roof.
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Rain is not a cleaning method.
Rain rinses off the loose dirt, then evaporates and leaves the dissolved minerals behind as a film. The panel looks clean from the street and still underperforms. Only fully deionized water dries to nothing.
| Measured against a clean baseline | Left aloneDust · salt · droppings | Rain or tap waterMineral film remains | Pure water cleanDeionized · zero residue |
|---|---|---|---|
| Output loss | ~25% | ~12% | ~0% |
| Lost per month — 10 panels | $51 | $24 | $0 |
| Lost per month — 20 panels | $102 | $49 | $0 |
| Lost per month — 30 panels | $153 | $73 | $0 |
| Mineral deposits | Heavy | Light film | None |
| Warranty risk | Soiling not covered | Some detergents void cover | None — water only |
Figures use PG&E residential rates at $0.32/kWh and a typical San Francisco array. Your own numbers depend on system size, orientation and how long it's been since the last clean — we'll work them out with you on the call.
Three steps, about an hour, nobody on your roof.
We test the water
Tap water goes through the deionizer until a TDS meter reads under 10 ppm. If it doesn't read clean, we don't start.
We wash from the ground
A 30 ft carbon fibre pole with a soft brush reaches most San Francisco roofs from below. No ladders on your gutters, no footprints on your tiles.
It dries to nothing
Pure water has no dissolved solids, so there's nothing left to dry into a spot. No squeegee, no towels, no streaks.
Published, per panel, no site visit needed.
Count your panels from a photo or your inverter app and you know the price before you call.
- Full deionized water wash
- Visual check for cracks, lifted clamps, debris
- Before and after photos sent to you
- Spring clean after the pollen
- Autumn clean before the rains
- Priority scheduling, cancel any time
Ground-level access included. Steep or restricted roofs may need a site visit first — we'll tell you on the phone, not after we arrive.
Four things worth knowing before you hire anyone.
Water only, nothing else
No soap, no solvents, no wax coatings. Detergent residue attracts dust faster than the dirt you removed, and some panel warranties exclude chemical cleaning outright.
Built for the fog belt
San Francisco panels get salt film off the marine layer and go dry from May to October. That's a different soiling profile from inland dust, and it's the one we work in every week.
All electric, under 60 dB
The pump runs off the truck battery. No petrol engine means we can start at 7am in Noe Valley without a neighbour filing a noise complaint.
Cleaning only — we're honest about it
We wash panels. We don't install, rewire, or modify systems, and we'll tell you plainly when something needs a licensed solar contractor instead of us.
San Francisco, and only San Francisco.
One city, one truck, same person on the phone and at your house. Highest solar density first:
Straight answers.
How often do panels actually need this?
Twice a year suits most San Francisco homes — once after spring pollen, once before the winter rains. If you're near the ocean, under trees, or have birds nesting under the array, three times is more realistic.
Won't the rain do it for free?
Partly. Rain lifts the loose material, then evaporates and leaves every dissolved mineral it was carrying on the glass. That film keeps costing you output until something removes it, and rain can't — it's the thing depositing it.
Will this void my panel warranty?
No. Panel manufacturers specify water and a soft brush. What causes warranty trouble is pressure washing, abrasive pads, and detergents. We use none of them.
Do you need to get on my roof?
Usually not. The pole reaches most San Francisco rooflines from the ground. On the rare job that needs roof access we'll say so before booking, never after.
Do you need my water or power?
No. We carry our own tank, our own deionizer, and a pump running off the truck. Nothing to plug in, no hose bib to find.
Are you insured?
Yes — general liability, certificate available on request before we book.
Tell us how many panels.
That's genuinely all we need for a price. We'll come back the same day with a number and two dates.