The national average cost for residential solar panel cleaning is $133. Rates may be higher or lower depending on your zip code, total number of solar panels, and accessibility factors—such as roof height. Industry experts recommend cleaning your solar panels twice per year to keep them at their peak power output. As a homeowner you can wash your solar panels yourself, but if you’re not using the right equipment or properly treated water, you can actually do more harm than good. Improper cleaning can scratch the surface or cause water stains to build up over time, diminishing the efficiency of the panels. If you have a high roof, have hard water or don’t have the proper gear, protect your investment and leave solar panel cleaning to the pros. Here’s a breakdown of what it costs to have your solar panels professionally cleaned.
What's in this cost guide?
- What affects the cost of solar panel cleaning?
- How much does cleaning solar panels cost?
- Solar panel cleaning price per panel
- Solar panel cleaning flat rate
- How to hire a cleaning company
- Ways to save money on solar panel cleaning
- Benefits of cleaning solar panels
What affects the cost of solar panel cleaning?
The cost of cleaning solar panels is affected by where you live, local labor costs, the number of solar panels you have, how many stories your home is, and how accessible your panels are. Professional window cleaning companies may charge by the number of panels or set a flat rate.
How much does cleaning solar panels cost?
As noted above, the national average cost to clean solar panels is $133, which can vary by region and by factors such as accessibility and number of solar panels.
Solar panel cleaning price per panel
Some window washing companies offer a per-panel cost when calculating your estimate for solar panel cleaning. The cost will account for employee labor, travel to your location, materials and the size of the job. Per-panel costs will also vary with the cost of living in different regions of the country. Here is one example of a per-panel price range:
|Price per panel||Factors impacting cost||Location|
|$5-$10||Size of panels, location of panels and accessibility||Crystal Clear Window Washing in Encinitas, California|
|$8||Panels on a second story house||Crystal Clear Window Washing in Encinitas, California|
Solar panel cleaning flat rate
Window washing companies may offer a flat rate, up to a certain number of panels. The rate is calculated to include the cost of employee labor, transportation costs, materials required for the job, business overhead and regional cost factors. Windsor of Window Genie of the East Valley in Gilbert, Arizona, says that the number of panels to be cleaned matters more to the cost than the brand or style of panel. Most panels are approximately 2.5 feet wide by 4 feet tall, says Windsor. Window Genie of the East Valley calculates rates as follows:
- Up to 32 solar panels: $129-$149.
- A job this size typically takes 1.5-2 hours.
- Each additional panel over 32: $2.50 per panel.
- Discounts are available for commercial or large accounts that have large numbers of panels, providing a lower cost per panel.
How to hire a cleaning company
When hiring solar panel cleaners, look for a company that specializes in solar panels, not just general window washing. Your solar installation company may provide a solar maintenance package that includes regular cleanings. Reading reviews will help you narrow down potential cleaning companies. Ideally you can create an ongoing relationship with the company to come twice a year and keep your panels in peak condition. Inquire about what type of cleaning solution the company uses, what safety measures and liability insurance the company has, and how they determine their rates. Clarify how and when payment will be made and what to expect during the process.
Ways to save money on solar panel cleaning
You can save money on your solar panel cleaning if it’s safe to DIY and you have the proper equipment. Cleaning solar panels can be a straightforward task for a homeowner:
- First, ensure you can safely access your panels from the ground. Climbing on the roof with soapy water and a brush is not a good plan
- Contact your solar panel installation company regarding manufacturer guidelines for cleaning your panels
- Verify that your hose water won’t leave mineral deposits on your panels
- Fit a soft-bristled brush to an extension pole and prepare a bucket of warm, soapy water with an approved cleaning solution
- Don’t use a pressure washer, which can damage your solar panels
- Gently clean away bird droppings, dust, and other build up
- Avoid washing in the hottest part of the day, as the soap may dry and leave a residue
Benefits of cleaning solar panels
Besides improving the overall aesthetics of your home, having your solar panels professionally cleaned on a regular basis has financial benefits in the form of lower energy bills and longer solar panel lifespan.
Cleaning solar panels on a regular basis helps ensure optimal power output of renewable energy. Solar panels that aren’t properly maintained can lose up to 30 percent of their efficiency, says Brent Windsor of Window Genie of the East Valley. That can lead to higher utility bills, defeating the purpose of installing solar panels in the first place.
In addition to safety, there are a number of reasons to have a pro clean your panels instead of doing it yourself. Pros use specialized, soft-bristle brushes that are non-abrasive and won’t scratch the surface of the panels. They also use soap that is approved for use on solar panels. Ordinary cleaning supplies can leave residue on the panels’ surface, which can decrease their efficiency, or even damage the electronics or corrode the framing.
Proper water for cleaning
Professionals will also be aware of the mineral content of your local water. "In Arizona, our water is very hard," says Windsor with Window Genie of the East Valley. “The EPA recommends avoiding drinking water with mineral counts of over 500; we’ve seen mineral counts up to 1,500 in our area.” Hard water that has not been properly filtered can leave water spots and stains on your solar panels, cleaning away the dirt, but leaving behind a mineral residue that reduces the intake of the sun’s rays over time and decreases your energy absorption. Depending on the mineral content in the area, companies will use different processes to prep the water to properly clean your panels. In Arizona, Windsor with Window Genie of the East Valley uses an onsite water de-ionizer that brings the mineral count of the water down to below 9 parts per million, making the water spot-free. "If you don’t use the right type of water and allow hard water stains to build up, you can permanently damage your solar panels," says Windsor with Window Genie of the East Valley.