How to start a solar panel cleaning business: water-fed poles, pure water, safety and pricing

Why do solar panels need cleaning, and who pays for it?

Dirty panels make less power. Dust, pollen, ash, bird droppings and road or farm grime sit on the glass and block light; the loss is called soiling. Homeowners, solar installers and the owners of commercial arrays pay to remove it when rain has not, and the business case is strongest where it rarely rains and dust is constant.

Sandia National Laboratories’ PV Performance Modeling Collaborative describes soiling losses this way: dust, soot, organics and other particulates accumulate on module surfaces over time, absorbing and scattering some fraction of the light before it enters the module; the magnitude depends on the type and amount of material since the last cleaning; some soiling is cleaned naturally by precipitation while other types require manual washing. It notes that proximity to dusty agricultural fields, smoggy roadways and industrial sites changes the rate.

How much production comes back after a cleaning varies with how dirty the array was. EnergySage, a solar marketplace, quotes a San Diego cleaning company owner saying his customers typically see a 10% to 25% increase in performance depending on how dirty the panels were, and puts professional cleaning at around $150 to $350 (EnergySage). Treat the percentage as one operator’s experience, not a promise: your own before-and-after readings from the client’s monitoring app are the honest proof, and they make the best sales tool you have.

Who buys

• Homeowners with rooftop arrays, especially where panels sit at a low tilt, under trees, or near farms, freeways and the coast.
• Solar installers who want a maintenance partner for their customers, or who bundle a yearly cleaning with their service plans.
• Commercial and agricultural owners: warehouse roofs, carports, schools, ground-mount arrays on farms, where output is tracked and a few percent is real money.
• Property managers and HOAs with community solar or shared carports.

If you already clean windows, this is the closest add-on there is: same pole, same water, same clients. The window cleaning business guide covers the water-fed pole trade in general; this page covers the solar side.

How are solar panels cleaned professionally?

With pure water, a soft brush on a long pole, and no soap: deionized water fed through a water-fed pole scrubs the glass and rinses it, then dries without spots because there are no dissolved minerals left behind. You work from the ground or a ladder for most residential roofs.

The standard method

1. Confirm the array is safe to approach: no damaged panels, no exposed wiring, and the inverter and monitoring app show a baseline you can photograph.
2. Work early morning or late afternoon when the glass is cool. Cold water on hot glass can crack it, and water evaporates too fast at midday.
3. Rinse first to float off loose grit, so you are not grinding it across the glass.
4. Scrub with the soft brush of the water-fed pole, panel by panel, overlapping strokes, paying attention to the lower edge where dirt collects against the frame.
5. Final rinse with pure water only. No squeegee, no towel, no soap.
6. Photograph the clean array and, when the client shares it, the production reading an hour later.

What never to do

• No pressure washing. High pressure can damage seals, frames and anti-reflective coatings.
• No abrasive pads, no metal tools, no harsh chemicals or solvents. Sunrun’s cleaning guidance, for example, describes soft-bristle brushes and mild, non-abrasive cleaning done from the ground with a long-handled brush, and warns about soap residue if you do use soap (Sunrun). Pure water avoids the residue problem entirely.
• No walking on panels, ever.
• No cleaning without checking the owner’s panel and installer warranty terms. Some specify cleaning methods; document that you followed them.

Bird droppings, lichen and stubborn soiling

Soak, then brush; repeat. A longer dwell with pure water does more than force. For heavy lichen or baked-on residue, a mild, manufacturer-approved cleaner and a thorough pure water rinse is the limit; if that does not work, say so and leave it rather than scratch the glass.

What equipment does a solar cleaning business need, and what does it cost?

A water-fed pole long enough for the roofs you serve, a pure water system (DI tanks alone where tap water is soft, reverse osmosis plus DI where it is hard), hose, a TDS meter to check the water, and a vehicle. At the dealer prices below, a 39-foot carbon pole kit plus a portable RO/DI cart comes to about $3,070; a full pure water rig costs more.

Prices below were listed in October 2026 by J. Racenstein and Tucker, two suppliers to the window and solar cleaning trade (Tucker showed both of its items as unavailable to order at the time); check their current pages and compare others (Unger, XERO and IPC Eagle are common brands).

DI only, or RO plus DI?

Deionizing resin strips the minerals that leave spots. In soft water areas a DI tank alone lasts a long time; in hard water areas it exhausts fast and a reverse osmosis stage ahead of it saves money. Measure your region’s tap water with a TDS meter before you buy, and aim for 0 ppm at the brush. Resin and filters are the main consumable, so track them per job.

The profit calculator shows how many arrays a month pay back the rig at your prices.

How do you clean panels safely: roofs, electricity and water?

Clean from the ground whenever the pole reaches. When it does not, use fall protection and a ladder set properly, treat every array as live, and never spray water at inverters, junction boxes or exposed connectors.

Falls

OSHA’s walking-working surfaces rule, 29 CFR 1910.28, requires employers to protect each employee on a surface with an unprotected side or edge 4 feet or more above a lower level, using guardrails, safety nets or personal fall protection. OSHA’s portable ladder safety card covers the setup basics: base a quarter of the working length from the wall, ladder extended at least 3 feet above the roof edge, three points of contact. Wet glass and wet roofs are slippery; the sales pitch of a long pole is also the safety plan.

Electricity

• Panels produce voltage whenever there is light, and strings in series can reach hundreds of volts. There is no off switch for the panels themselves.
• Inspect before you wet anything: cracked glass, chewed cables, open junction boxes and exposed connectors mean stop and tell the owner.
• Keep water away from the inverter, combiner boxes and any electrical enclosure. Spray the glass, not the hardware.
• Use non-conductive (fiberglass or carbon fiber with care) poles and keep metal ladders clear of wiring and overhead lines.
• For commercial arrays, follow the site’s lockout rules and get the operator’s written procedure before the first visit.

Water and the roof

• Pure water is not a pollutant, but it carries grime off the roof; keep it out of pools and direct it to landscaping or lawn where you can.
• Do not flood tile roofs or push water under shingles with an upward spray.
• Rinse the gutters afterward so the client does not see a line of sludge the next day.

Insurance follows the risks above: general liability with solar cleaning and work at height described, commercial auto, and workers’ compensation when you hire. Ask the agent about damage to panels, inverters and roofs, and whether work above a certain height is excluded. The cleaning business insurance guide covers the policy types.

How to start a solar panel cleaning business, step by step

Practice on a friendly array, register and insure the business, buy the pole and pure water system, set per-panel and tiered prices, and introduce yourself to every installer within an hour’s drive. Starting a solar panel cleaning business is cheaper than most trades, and the equipment is the same one you would use for windows.

1. Learn on real panels. Clean an array you can monitor, before and after, and keep the readings.
2. Register the business. Entity, name, EIN, bank account; the LLC guide covers the structure choice and how to start a cleaning business the shared steps.
3. Check local rules. Usually a general business license. Some states license solar contractors for installation and repair, which you are not doing; keep your scope to cleaning and say so in writing. See what licenses a cleaning business needs.
4. Insure before the first paid job.
5. Buy the rig sized to your market: a 30-foot pole and a DI tank for single-story suburbs, a 40-foot pole and RO/DI for two-story homes and hard water.
6. Write a short service agreement that states the method (pure water, soft brush, no pressure), what you inspect, and that production gains depend on how dirty the panels were. Adapt the cleaning contract template.
7. Set prices and a maintenance plan.
8. Visit installers and property managers with your before-and-after readings.

How much should you charge to clean solar panels?

Charge per panel with a minimum, or in flat tiers by panel count, with adders for steep or two-story roofs, ground mounts far from a hose bib, heavy soiling and bird mess. Residential jobs mostly land between about $150 and $350; commercial arrays are priced per panel at a lower rate with a site minimum. For a full price sheet by panel count, roof access and array size, see our guide to solar panel cleaning prices.

What the marketplace data says

Thumbtack reports a national average of $142 to $310 for solar panel cleaning, with most people paying about $209, a low end of $81 and a high end of $557. It gives two real pricing models from pros: a California company charging $5 to $10 per panel, and another charging a flat $129 to $149 for up to 32 panels (a job it says takes 1.5 to 2 hours) plus $2.50 for each panel over 32. EnergySage puts a professional cleaning at around $150 to $350.

A worked example (hypothetical numbers)

Say a 24-panel, single-story array takes one person 75 minutes on site plus 30 minutes of driving, at $24 an hour, with $8 of resin and $10 of fuel.

• Labor: 1.75 hours at $24 = $42
• Resin, filters, fuel: $18
• Direct cost: $60

With 30% of the price for overhead (pole and RO/DI payments, insurance, software, marketing) and 25% profit, direct cost is 45% of the price: $60 divided by 0.45 is about $133. Quote $135 to $150 for this array, which is about $6 per panel, with a $125 minimum so a 10-panel job still pays. A two-story roof adds ladder time and risk; price it higher. Write it up with the cleaning estimate template.

Commercial arrays

A 500-panel carport is not 500 times a residential panel. Access is easy, the panels are in long rows, and you may clean 100 or more an hour with a good setup, so the per-panel price falls to a fraction of the residential rate while the invoice is still four figures. Quote from a site visit, include the water source and any lift, and sell a schedule: the owner is tracking output and will see the dip when soiling returns.

How do you find solar cleaning clients?

Start with installers, because they already know every array in your area and get asked about cleaning constantly. Then work the neighborhoods where panels are visible from the street, and sell a maintenance plan to every client so each one books more than once.

• Solar installers. Offer to be their referral for cleaning, or to white-label a yearly cleaning inside their service plan. Bring your readings.
• Monitoring apps. Teach clients to compare this month with last year on the same app; the dip sells the next cleaning for you.
• Google Business Profile and local SEO. Photos of real arrays and reviews; the cleaning company SEO guide covers setup.
• Door hangers on streets with panels. You can see your prospects from the truck. The flyer template is a quick start.
• Window cleaners, pressure washers and gutter companies. They are on the same roofs; trade referrals, or add their services yourself. The pressure washing guide covers that side.
• Commercial owners and farms. Property managers, school districts, agricultural ground mounts. A written method, insurance certificate and a safety plan get you in.

Maintenance plans are the heart of the business: two to four visits a year in dusty regions, one or two elsewhere, each booked ahead and reminded automatically. Broombook is booking, scheduling and reminders for recurring service businesses, and it fits that recurring plan work (and any window or house cleaning you run alongside): a booking link with your prices, recurring schedules, reminders and a card on file charged after the visit. See the features page and pricing. For more channels, see how to get clients for a cleaning business.