Do solar panels in Michigan need cleaning, and what does it cost?

What a cleaning visit is and who should do it

A cleaning visit means a company washes the array, usually the whole system in one trip. Our model prices it both per visit and per panel. We don't suggest climbing onto a roof to do it yourself.

Michigan sets fall protection at six feet on residential construction work. MIOSHA's fact sheet, revised September 11, 2023, says residential construction employers must use guardrails, safety nets or personal fall arrest systems for work six feet or more above a lower level. Slide guards and safety monitors are no longer acceptable without a showing that the other methods aren't feasible. The sheet defines residential construction as building a wood-frame home and doesn't mention solar, so it doesn't settle what a cleaning crew must use. It's still why we'd leave the climbing to a company and ask what fall protection its crew uses.

Ask whether the company carries insurance, which the MPSC lists among the questions to put to any solar company alongside how long it's been in business and three customer references. Find out too whether its crew will be on the roof or working from the ground, and what it does if a panel or the flashing is damaged.

What panel cleaning costs in Michigan

Our estimate is $110 to $500 per cleaning visit, whole system, or $10 to $25 per panel cleaned. Treat both as planning figures, not quotes. The per-visit range rests on one published national range, widened 15 percent on each side because there's only one, then scaled by what Michigan solar installers are paid against the US mean. It adds no permit fee, and it doesn't cover roof access equipment beyond a normal visit or repair work found during it.

Use the per-panel range against per-panel bids and the per-visit range against per-visit bids.

How we estimate costs: the Estimated range row comes out of a model, so treat it as a planning figure and never as a quote. It takes one published national range for this job (a cost guide from a third-party site that we haven't verified and don't cite) and multiplies it by Michigan's solar installer wage ratio to the US (0.87, BLS May 2025). The range is before any incentive: the federal residential clean energy credit does not apply to systems installed after December 31, 2025. The wage and permit rows are what installers are paid and what the city charges, and neither is a price. We have not collected quotes, and too few Michigan installers publish prices to show a range. Full method. Prices as of Oct 23, 2026.

Does cleaning change what your system makes

Our run of NREL's PVWatts calculator, for a south-facing roof at 30 degrees with 14 percent losses, gives about 1,300 to 1,324 kWh per kW a year across five Michigan metros, from 1,300 in Grand Rapids to 1,324 in Detroit. A small share of that comes in the winter months. The tool's notes say shading, pitch and orientation change the result.

The national labs measure dirt in percent, and their figures aren't Michigan's. In an April 2021 piece about dusty places, NREL wrote that energy lost each year to soiling runs "as much as 7%" in parts of the United States. Rain and wind can scour some dust off, while dew can cement it on. NREL's soiling map of 255 U.S. locations, as of March 2025, reads a soiling ratio of 0.95 as a 5 percent yearly loss, and NREL says its method doesn't handle pollen well.

None of those labs prints a soiling figure for a Michigan system, so ask any company that promises a gain from cleaning to show its figure and where it came from. Your monitoring app or inverter display, read before and after a visit, is the record you can check yourself.

Snow on the panels and what the labs measured

Sandia National Laboratories says published estimates of snow losses run from 1 to 12 percent a year, with monthly losses as high as 100 percent depending on location and weather, and that snow puts uneven stress on modules. That's a national range, not a Michigan one. Michigan Tech and the University of Michigan are partners in Sandia's snow project.

Steep tilt sheds snow. Michigan Tech's 2013 story on a study at its Keweenaw Research Center quoted a researcher: "If you tilt them at 60 degrees, almost no snow sticks to the panels," though a steep tilt also loses sunlight. The yearly losses it cited, 12 percent at a 39 degree tilt and 18 percent flat, were measured near Lake Tahoe. NREL's snow model in its SAM software, described in a 2017 report, treats sliding as the main way snow leaves a tilted array.

Consumers Energy says shorter days and a lower sun cut winter output, that panels are built to keep generating through winter, and that the best solar production often comes in late winter when cold and clear skies combine. It wrote that about the utility-scale plants it's planning, not about home roofs. If a DTE site visit falls in winter, DTE's FAQ, as of September 2023, asks that panels be clear of debris such as snow and leaves, so ask your installer who clears them.

The credit rules behind any output claim

Before you pay for more output, know what output earns you. Under DTE's Rider 18 the power you draw is charged at the retail rate and the power you send out is credited at the power supply rate, which DTE says includes PSCR. Consumers Energy credits excess at the power supply rate, including transmission, against all electric charges.

For scale, EIA put Michigan's average residential price at 22.99 cents per kWh in August 2026, up from 20.73 cents in August 2025. August is a high-use month, so that's one month's price and not a yearly one, and it's an average price for power bought, not what an exported kWh is credited.

Check the warranty and the contract first

Before you book, ask the installer whether the panel warranty or the roof warranty says anything about cleaning methods, and get the answer in writing. The MPSC tells buyers to ask what warranties come with a system, and roof penetrations have their own flashing and sealing rule in Michigan's residential code amendment, R 408.30521a.

The method matters too. An NREL presentation from March 2018 lists cleaning trade-offs for PV in general: natural rainfall costs nothing but "may not be enough," high-pressure spray "may damage modules" and a dry brush "may scratch glass." A soapy hand squeegee takes labor and water. That's a lab survey, not advice for a home roof, so ask the company which method it uses and check the answer against your panel warranty.

Ask for the price before the crew arrives, and what it covers. A quote that says per panel needs your panel count, and a quote that says per visit needs to say whether it covers the whole array. The winter and snow guide covers snow separately.

If the crew finds something wrong

A cracked panel that isn't smoking can wait for a repair visit, which the solar repair page covers. Smoke, a burning smell or fire at the panels or wiring is a 911 call. Anything that touches the wiring belongs to a company holding a Michigan electrical contractor license, since the law's definition of electrical wiring covers generating equipment, so ask for that number and look it up with LARA before the work starts.

When to call 911 and when it can wait

What to do before you book

1. Read the panel and roof warranty papers.
2. Ask each company whether the price is per visit or per panel.
3. Ask whether it is insured and how it reaches the roof.
4. Ask what it does if a panel or the flashing is damaged.
5. Count your panels so you can compare per-panel and per-visit quotes.

Permits, licenses and insurance

The model adds no permit fee for a wash. If a visit turns into wiring work or an inverter swap, the Michigan electrical contractor license and the city permit apply, and Detroit issues its own licenses locally. Ask the company whether it carries insurance and what it does if something is damaged.

Ask for the company's contractor license number and look it up with your state's licensing board before you sign.

Questions people ask

Keep reading

Guides

• Winter and snow on solar panels: what to read in your papers and who to call
• Solar quotes: what to compare, and what to get in writing, before you sign
• Battery storage basics: backup power, export credits and what the incentives say in 2026
• Roof age and solar: when to replace the roof first, and what the codes say about the roof itself

Related services

• System inspection
• Solar repair
• Inverter replacement
• Solar panel installation

Michigan licensing, code and permit facts · How to check a solar installer's license · Report a wrong price or rule