Utility-scale solar panel cleaning by drone soft-wash. StratoClean cleans ground-mount, single-axis tracker and fixed-tilt arrays touchlessly — nothing rolls between the rows, nobody walks on a module, and the array does not have to be shut down to be cleaned.
The problem with cleaning a solar farm the usual way
At utility scale, the cleaning method is an access problem before it is a cleaning problem. Brush rigs have to fit the row pitch and need ground firm enough to carry them. Hand crews have to walk every row, in heat, for days, and coverage drifts as the crew tires. Rail systems only exist if somebody paid to install them row by row. And every one of those options puts something abrasive on an anti-reflective coating your module warranty assumes nothing will ever touch.
Flying the pass removes the access problem entirely. Row spacing, wet ground, tracker position and terrain stop being constraints, because the cleaning head arrives from above.
What a StratoClean utility-scale pass looks like
- Site assessment. Block layout, module count and type, row pitch, tracker or fixed-tilt, soil type, water access on or near site, gate and staging access, and whatever your O&M plan already commits to on cleaning frequency.
- Water plan. Purified water for the final rinse is what leaves glass spot-free. Where it comes from on your site is settled before mobilization, not on the morning of.
- Block-by-block passes. We work in defined blocks so coverage is verifiable and your inverter-level data can be read against it afterward.
- Controlled dwell, then rinse. A panel-safe biodegradable solution is applied at low pressure, given time to release the soil, then rinsed with purified water.
- Documentation. Date, time, blocks covered, water source, solution class, operator. Filed the way an O&M plan expects it. See cleaning records and reporting.
Day or night — your choice
Cleaning during production hours costs you generation in the exact hours the plant earns most. We fly solar farm cleaning at night so the wash costs no generating hours, and the glass is cool while we work — which also means the solution does not flash-dry and the rinse does not spot.
| Method | Contact with the glass | Downtime | Where it struggles |
|---|---|---|---|
| Drone soft-wash (ours) | None — nothing touches the module | None; the array keeps running, or we fly at night | Very high wind; sites with no water access |
| Tractor / vehicle-mounted brush rig | Rotating brush on the glass | Row access needed; rig has to fit the row spacing | Tight row pitch, soft or wet ground, uneven terrain, trackers mid-travel |
| Hand crews with poles and brushes | Brush and pole contact | Slow; crews walking the array for days | Labor hours, heat exposure, module-walking risk, inconsistent coverage |
| Fixed / robotic rail systems | Brush contact, permanently installed | None once installed | Capital install per row; retrofit rarely pencils |
Array types we clean
- Utility-scale ground-mount, fixed-tilt and single-axis tracker
- Bifacial modules (see trackers, bifacial and fixed-tilt)
- Large commercial and industrial rooftop arrays, carports and canopies
- Agrivoltaic and dual-use sites where ground equipment cannot drive the rows
- Municipal, campus, hospital and stadium arrays — often alongside facade and window scope
Frequently Asked Questions
How do you clean a utility-scale solar farm without shutting it down?
The array keeps generating while we fly. Nothing is driven between the rows and nobody walks on modules, so there is no reason to de-rate or curtail a block to let a crew in. On sites that prefer it, we clean at night instead, when there is no generation to lose at all.
Is drone cleaning better than a tractor-mounted brush rig?
It is better where access or contact is the constraint — tight row pitch, soft or uneven ground, trackers, or any owner who does not want an abrasive brush running across an anti-reflective coating. Brush rigs move fast on wide, flat, dry, fixed-tilt rows; that is their best case and we will say so.
How often should a utility-scale array be cleaned?
It depends on what is landing on it, not on the calendar. Agricultural dust, coastal salt, pollen season and bird pressure all set their own intervals. The honest answer comes from your own production data: soiling shows up as a widening gap between expected and actual output that rain does not close.
Does rain clean solar panels enough?
Rain removes loose dust and does very little about anything bonded — bird droppings, pollen film, salt crust, agricultural dust that has been wetted and baked. It also re-deposits soil at the bottom edge of the module as it runs off, which is where the cells shade first.
Will cleaning void my module warranty?
Module warranties generally set limits on what may touch the glass, what pressure may be used, and what chemicals are acceptable. Touchless low-pressure washing with a panel-safe, biodegradable solution and a purified-water rinse is designed to stay inside those limits. We are glad to review your module manufacturer’s cleaning guidance before we quote.
Do you use deionized or purified water?
Yes — the final rinse is purified water, and that is the part that decides whether glass dries clear or dries spotted. Tap-water minerals dry as spots that shade cells and undo the clean.
What does utility-scale solar cleaning cost?
It is driven by array size, module count, access, soil type, water availability on site, frequency and documentation requirements. What drives solar farm cleaning cost breaks down each factor; the number itself comes from the site assessment, which is free.
