Flat or gently sloped roof
A shallow slope traps more dust, pollen and debris than a steep roof, where rain naturally does part of the work.
Clean panels, production back on track.
Soft brush, deionised water and a product made for photovoltaic glass: we clean your system panel by panel, then dry the glass with a squeegee. A simple step to get back the yield of a clean roof.
- Free on-site study
- Detailed quote within 7 days
- Cantonal subsidies handled
- Direct installer
Why clean them
Soiling eats into your production.
Dust, pollen, bird droppings or urban pollution build up in a fine layer on the modules — invisible from the ground, but very real on the active cell surface. On a shallow roof or near a main road, this gradual soiling can cost several percent of yield without any warning sign.
Done properly, cleaning gives the glass its active surface back without harming it: soft-bristle brush, deionised water and a product made for photovoltaics, never high pressure. Yield climbs again, and the check that follows spots what is hard to see from the ground.
up to 15%
Yield loss observed on a soiled roof
from CHF 249
Cleaning package for a residential system
before / after
Photo report sent for every visit
~30 min
Average duration for a residential system
Our approach
From the first call to the photo report.
Initial contact
A quick phone call to assess your system: number of panels, roof height, access. We confirm whether your roof qualifies for the standard package.
Cleaning with the telescopic brush
Soft brush, deionised water and a product made for photovoltaic glass, panel by panel. We finish with a squeegee and an absorbent sleeve, so the glass dries mark-free.
Visual inspection of the system
Checking the mounting hardware, visible wiring, and any sign of corrosion. Any issue found is reported, with a service follow-up proposed if needed.
Before/after report
Before/after photos are sent once the job is done. With the CHF 399 package, the report also lists what the technical check picked up.
On site
Your panels as clean as day one!
The footage below comes from a real visit on a residential roof, from the first look to the final result.
- 01 · Before
A film you cannot see from the ground
Dust, pollen and moss along the roof edge build a continuous film on the glass. Up close, the active surface is no longer really black.
- 02 · Brushing
Soft brush, deionised water
The brush works panel by panel, with a product made for photovoltaic glass. No high-pressure jet, no abrasive contact.
- 03 · Rinsing
A rinse with pure water
The deionised water carries away what the brush has lifted. With no limescale, it leaves nothing behind on the glass.
- 04 · Drying
Squeegee, then absorbent sleeve
We pull the water off panel by panel with the squeegee. An absorbent sleeve then picks up the last drops, without scratching the glass.
05 · AfterThe glass reflects again
Same roof, two hours later. The panel mirrors the sky again: the simplest sign of a surface handed back to the sun.
On this roof, access was safe to walk on. Depending on the setup, we work from the roof or from the ground with the telescopic brush.
Case study · Liestal (BL)
After cleaning, the system produces clearly more.
On 12 October, under a clear sky, it topped out around 4.2 kW. On the 15th, after our visit, it passed 5 kW several times despite a changeable sky. With a video of the visit and readings from the monitoring app.
- Before · 1:20 pm
- 4.18 kW
- After · 1:20 pm
- 6.94 kW
Roof moss removal
What if the moss has spread to the roof?
On the job shown above, moss had settled along the modules. Cleaning removes it from the glass and frames. If the roof covering itself is overgrown, we offer full roof moss removal.
Best done before a new installation
Once panels are mounted, the roof covering can't be reached without taking them down. Removing moss beforehand saves a return trip to the roof.
A sound roof under the panels
Moss holds moisture, lifts tiles and clogs gutters. Under a system built to last 25 years or more, the roof covering should start out clean.
A treatment suited to your roof
Brushing, low-pressure rinsing and an anti-moss product suited to tiles, slate or fibre cement. Never high pressure, which damages tiles.
Roof moss removal and treatment
from CHF 1'800
Price confirmed at the technical visit, depending on area, pitch and access.
2026 pricing
Published pricing.
The quote is confirmed after a short chat about your system. No hidden fees.
| Service | Price |
|---|---|
| Cleaning only (up to ~30 panels) | CHF 249 |
| Cleaning + technical check (inverter, mounts, cabling) | CHF 399 |
| Large roof (over 100 m²) | CHF 4 / m² |
| Complex access surcharge (tall roof, obstacle) | +CHF 90 |
| Roof moss removal with anti-moss treatment | from CHF 1'800 |
Who it's for
Four situations that call for a cleaning.
Near a main road, farmland or an urban area
Traffic dust, agricultural pollen or urban pollution build up in a fine layer, invisible from the ground but measurable in your yield.
Secondary residence or hard-to-reach roof
You don't walk past your system every day. We bring our own equipment and water, so there is nothing for you to prepare.
System over 3-4 years old with no maintenance
Soiling builds up gradually and is often underestimated. A check-up and cleaning confirms whether production still matches expectations.
Our commitment
The same team that installed your panels.
Glass left dry and mark-free
Squeegee then absorbent sleeve after the rinse: no limescale film as it dries, no scratches on the modules.
Deionised water and a dedicated product
A product made for photovoltaic glass, with no risk to the seals or the anti-reflective coating of the panels.
Technicians trained on solar installation
The same I.ON team that installs your panels knows how to handle them safely.
Public, fixed pricing
Quote confirmed before the visit. No surprises, no hidden call-out fees across Western Switzerland.
FAQ
Your questions about solar panel cleaning.
Is cleaning solar panels really worth it?
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Yes, in most cases. A layer of dust, pollen or bird droppings reduces the active cell surface and can cost several percent of yield, more so in locally soiled spots (droppings, plant debris). The effect is stronger on shallow roofs and systems near a main road or farmland.
How often should solar panels be cleaned?
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Once a year is enough in most situations in Western Switzerland, since rain provides partial natural upkeep. Two visits a year are recommended for flat roofs, dusty or agricultural environments, or after a heavy pollen spring.
Does cleaning void the manufacturer's warranty?
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No — quite the opposite: cleaning done properly (deionised water, soft brush, a product made for photovoltaic glass, no high pressure) is part of the standard care recommendations from most manufacturers. It's aggressive cleaning or an untrained operator that can cause issues.
Do you need scaffolding or a lift platform?
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In the vast majority of cases, no. Our telescopic equipment covers nearly all residential roofs (2 to 3 storeys). A surcharge only applies to tall roofs or very restricted access.
What's the best season to clean solar panels?
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Late winter or early spring, before the summer production peak and after the period when pollen and debris build up the most. A second visit in late summer is useful if your surroundings are dusty.
Can cleaning damage the panels?
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No, if done correctly. Soft-bristle brush, deionised water and a product made for photovoltaic glass, then a squeegee to dry. No high-pressure jet, no abrasive contact with the panel glass.
What does the CHF 399 package include?
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A full clean of the system, followed by a technical check: inverter and error messages, mounts, visible cabling, condition of the modules. You get the photo report and the points to keep an eye on. Choose it if your system has not been checked for several years.
More questions about your solar system? Visit our solar panels page or our full FAQ.
