How To Clean Solar Panels, How Often, & Maintenance Trick for Max Power

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Solar Panels | April 1, 2024

Man wearing rubber gloves and glasses with cleaner spray looks at a dirty solar panel and wonders how to clean solar panels and if there is a solar panel cleaning guide that explains solar panel maintenance such as how to clean solar panels on roof and solar panel washing tips.

Installing solar panesl on your home to supplement, or fully power it is an awesome way to help the planet, but did you know that learning how to clean solar panels correctly can have an impact on the performance of your panels?

It’s true.

Dirt, dust and grime can interfere with the productivity of the panel and also shorten its lifespan.

And, you can’t simply count on the rain to do it for you.

Fortunately, it’s not as complicated as it sounds.

Knowing how to clean solar panels – and how not to clean solar panels – is essential to maintaining their energy efficiency. Fortunately, cleaning most solar panels is closer to household cleaning than industrial labor.

Common household items and common safety measures can keep the solar panel operating optimally.

You can easily learn how to clean solar panels and how often you should do it using this complete guide…which will ensure that you retain maximum power output.

Where Can I Learn How Often To Clean Solar Panels?

Due to external factors such as varying climates, the physical placement of the solar panels, and the location’s fauna and pests, there is no standard answer to how often solar panels should be cleaned.

Environments that are more prone to dust accumulation – such as deserts with low precipitation and high winds – will require solar panel operators to perform more frequent cleaning.

Visible accumulation of debris and significant reductions in energy capture are strong indicators that solar panels are due for cleansing.

Visual inspections and energy monitoring will often indicate when a solar panel needs to be cleaned. When a solar panel looks dirty or starts to produce less energy, you should take care of it.

How To Clean Solar Panels: 7 Steps

Fortunately, the techniques used for cleaning household windows are exactly how to clean solar panels.

Simply spraying water removes most of a solar panel’s grime, and the combination of a non-abrasive brush and glass-friendly cleaners can take care of more difficult impurities such as biological stains.

Graphics of how to clean a solar panel showing the 7 steps to clean a solar panel with water.

The only major complication is applying safety precautions.

Homeowners and cleaning personnel should ensure that solar panels are powered off during cleaning.

It’s also a good idea to ensure that the panel can be accessed safely, so never do the job on a roof by yourself.

How To Clean Solar Panels From the Ground

Cleaning solar panels from the ground is not different from cleaning common glass fixtures such as windows and glass doors.

However, it’s vital to focus solely on the reflective side of the solar panel and avoid contact with a solar panel’s underside.

How To Clean Solar Water Heater Panels

Unless the manufacturer’s documentation states otherwise, the guidelines on how to clean solar panels are the same for cleaning solar water heater panels.

Consider hiring a professional if the solar water heater panels are installed on high places such as roofs that feature a steep grade.

How To Clean Solar Panels on Garden Lights

The process of cleaning solar panels on garden lights is like cleaning household and industrial-sized solar panels.

Though non-abrasive household cleaners are often sufficient, checking the manufacturer’s documentation is advised.

Typically, it’s safe to use a window cleaner on these easy-to-reach solar panel garden lights.

How To Clean Cloudy Solar Light Panels

The process of cleaning solar light panels uses similar materials and steps as cleaning solar panels.

Solar light panel operators should focus on cleaning the plastic and erring on the side of using non-abrasive cleaning tools and solutions.

If you have cloudy panels, it may be an issue with the manufacturing, or the panels could simply be aging. In either case, check with your manufacturer first. They may have a simple solution.

How To Clean Solar Panels on Roof

Contracting a third-party solar cleaner is ideal for rooftop installations that you cannot safely reach on your own.

A worker wearing safety suit stands on top of a solar panel while cleaning it with a big mop.

(Image: Maddybris6)

If you do not have the equipment and training to reach precariously placed solar panels, contact professionals.

How To Clean Solar Lights

Treat solar lights the same way you would treat solar panels.

Make sure that the photovoltaic panel is clean, without dirt and grime, and check it every month.

Solar Panel for AC Unit: Cleaning Considerations

Solar-powered AC units frequently require multiple solar panels to operate properly.

However, unless the manufacturer’s documentation states otherwise, the guidelines and tools for cleaning a solar panel for AC unit are the same as how to clean solar panels for other uses such as general energy generation and water heating.

Cleaning Solution for Solar Panels

With regards to cleaning, most solar panels can be treated similarly to household windows. Cleaning solutions commonly found in supermarkets are acceptable if they’re non-abrasive.

Mixtures of soap and water will work as well, but it’s advisable to strongly dilute the soap (to prevent any leftover buildup).

Most of a solar panel’s dust and debris can be removed with water. Rainwater acts as a natural dust remover. Hoses are an acceptable solution if the water is soft, and it is sprayed from a safe distance.

However, there’s more to solar power than installing a panel and enjoying sunny days and lower electricity bills.

Maximizing the benefits and lifespan of solar panels requires consistently monitoring and maintaining the panels.

Carbon Footprint: Solar Panels Lower More Than Utility Costs

When properly implemented and installed, solar panels can be a powerful method of reducing the amount of carbon dioxide in our atmosphere.

Large solar panels in a grassy field under a partly cloudy sky.

(Image: Atimedia5)

Addressing the climate change crisis and reducing the global carbon footprint will require multiple actions at once.

Switching from dirty energy sources – such as oil and natural gas – to environmentally-friendly energy will be crucial to the world’s survival.

Cities, groups, and individuals switching to renewable energy such as solar power will be one crucial step toward reducing the average American’s carbon footprint.

One acre of solar panels generating clean energy can generate up to 447 megawatts per hour; replacing an equivalently-producing dirty fuel with carbon footprint solar panels can lower the release of carbon dioxide by 138 metric tons a year.1

Although solar panels have a heavy eco-cost during production and disposal, the current benefits, especially to homeowners, is significant.

Benefits of Cleaning Solar Panels

Maintaining energy efficiency is one of the most vital benefits of cleaning solar panels. Dust, grime, and biological stains block the sun’s rays, so routine cleaning is crucial to maximizing energy efficiency.

Routine cleaning also extends the lifetime operation of solar panels. Removing stains and particles before they can inflict long-term damage is a key component of solar panel maintenance.

Consequences of Leaving Solar Panels Dirty

Failure to routinely clean solar panels can dramatically reduce their energy efficiency. One month of gathering dust and other ray-blocking impurities can lead to a 30% drop in a solar panel’s energy-capturing ability.2

In addition, excessive buildup of dirt and grime can damage solar panels. Biological waste and large quantities of dust can cause problems such as scratches and hot spots.

Size of Standard Solar Panel: Myths Versus Reality

The size of standard solar panel depends on the size of its solar cells, the number of its solar cells, and its intended use. Most solar panels used for residential and industrial buildings have square cells with side lengths of 156 millimeters (approximately 6.14 inches).3

Solar panels for residential use commonly have 60 cells. When those cells are arranged in a 6-by-10 grid, the resulting solar panel would be 1.56 meters long (roughly 5.12 feet) and 0.94 meters wide (about 3.07 feet).

Solar panels for commercial use often have 72 cells. When those cells are arranged in a 6-by-12 grid, the resulting solar panel would be 1.872 meters long (roughly 6.14 feet) and 0.94 meters wide (about 3.07 feet).

Solar Panel Cleaning Tips

Prior to any cleaning attempts, review the documentation that corresponds to the solar panels. Solar panels can vary significantly by manufacturer, so complying with the manufacturer’s instructions and warnings is essential when formulating how to clean solar panels.

Clean their solar panels during the coolest parts of the day. Excessive heat can cause water and cleaning solutions to evaporate, which can lead to efficiency-reducing smears and streaks.

So, early morning or late evening is the best time.

Since solar panels are electrical devices, an error can seriously injure a person who is attempting to clean it without the proper access, or damage the solar panel. This is especially the case for solar panels installed in high areas such as residential roofs.

Avoiding Common Mistakes During Solar Panels Washing

Non-professionals should not leave the ground in attempts to clean solar panels. High and hard-to-reach solar panels should be treated by professionals who have the experience, training, and equipment to safely reach and cleanse them.

Cleaning materials that scratch household glass will also scratch solar panels. Applying hard water and coarse cleaning agents will permanently damage solar panels.

Do not attempt to clean any part of the solar panel other than the surface.

Attempting to clean the underside of the solar panel or other concealed parts could lead to injury or damage.

Solar Panel Maintenance

Regular monitoring is the best method for solar panel maintenance.

Routinely monitor solar panels’ energy efficiency as well as any indicators or alerts from inverters and other monitoring tools.

A man wearing a safety help is kneeling at the bottom part of the solar panels checking for anomalies.

(Image: Gustavo Fring7)

Consistent exposure to shade, in addition to lowering solar panels’ energy collection, can damage solar panels. When shade routinely or completely covers a solar panel, the solar panel can develop hot spots, parts of the solar panel whose temperature is significantly higher.4

Failure to resolve consistent shade issues could drastically reduce the solar panel’s lifespan or completely break it.

Do Solar Panels Need Cleaning?

Do solar panels need cleaning regularly? Yes. Knowing how to clean solar panels is essential to preserving their energy efficiency.

Solar panel system on roof with snow build up.

(Image: Photo by Terry Thompson U.S. Department of Energy8)

Accumulation of dust, grime, and other impurities can dramatically lower the amount of energy they capture.

And some types of grime can permanently damage solar panels.

How Much Does It Cost To Clean Solar Panels?

Cleaning residential solar panels at ground level can frequently be completed with household items and over-the-counter cleaning tools. The cost for these do-it-yourself cleanings is comparable to the cost of a bag of groceries.

Professionals typically charge between $15 and $25 per panel. In addition, they may charge between $150 and $300 for panel inspections.

Do I Need To Turn off Solar Panels To Clean Them?

Solar panels must be deactivated prior to any cleaning attempts, even if no liquids are being used.

Solar panels that are actively collecting energy pose electrical hazards for those who would attempt to clean them.

How Long Do Solar Panels Last?

Solar panels’ operational lifetime varies due to a variety of factors, including the type, the manufacturer, and the environment.

However, some types of solar panels, properly maintained, can operate for up to 30 years before they need to be replaced.

Do Solar Panels Work on Cloudy Days?

Solar panels can capture indirect sunlight.So, when asking, do solar panels work on cloudy days, the answer is yes, but limited.

Although the energy generated from indirect sunlight is lower, solar panels can still function and generate electricity on cloudy and overcast days.

Solar panels in the middle of the field during cloudy day.

(Image: Coernl9)

As an unintended benefit, cloudy days can make solar panel cleaning easier. Overcast days with lower temperatures give you additional flexibility when scheduling cleanings, as the cloudy weather often leads to lower temperatures.

Also, rainfall acts as a natural dust remover, washing away loose particles that accumulate on the solar panel.

When Is the Best Time of Day To Perform a Solar Panel Wash?

A general rule of thumb is to clean solar panels at the coolest parts of the day. Like watering plants, cleaning solar panels in the morning prior to peak heat is optimal, though an early-evening cleaning will suffice.

Cleaning solar panels can sound like a daunting task at first.

The process is very similar to cleaning windows and glass doors. Applying soft, soapy water and a soft-bristled brush once a month is often as complicated as cleaning solar panels can be.

And the benefits of these easy and cheap actions can be dramatic. Consistent and careful solar panel cleaning can maximize the solar panel’s lifespan and energy capture.

And a few minutes of washing solar panels can prevent costly and time-consuming technical issues that would otherwise require costly repairs or replacements.

However, it’s imperative to ensure that solar energy is applied in an environmentally friendly way and treated as part of a multi-faceted solution instead of a cure-all. Failure to properly clean and maintain solar panels can negate their benefits or even be detrimental in terms of energy consumption and environmental impact.

Related Reading: Solar Panel Carbon Offsets

Proper installation and usage of solar panels can be an effective way to reduce carbon emissions, but solar panels’ benefits – both to the person who is cleaning them and to the environment – can be enhanced when you know how to clean solar panels correctly.


1Eisenson, M. (2022, October 26). Solar Panels Reduce CO2 Emissions More Per Acre Than Trees — and Much More Than Corn Ethanol. Columbia Climate School. Retrieved March 9, 2023, from <>

2Chandler, D. L. (2022, March 11). How to clean solar panels without water. MIT News. Retrieved March 9, 2023, from <>

3Wikipedia. (2023, March 9). Solar cell. Wikipedia. Retrieved March 9, 2023, from <>

4Tinker, L. (2016, September 16). Getting the Most out of Solar Panels. Energy Gov. Retrieved March 9, 2023, from <>

5Photo by Atimedia. Resized and Changed Format. Pixabay. Retrieved from, <>

6Photo by Maddybris. Resized and Changed Format. Pixabay. Retrieved from, <>

7Photo by Gustavo Fring. Resized and Changed Format. Pexels. Retrieved from, <>

8Photo by Terry Thompson for the U.S. Department of Energy / Public Domain. Resized and Changed Format. Flickr. Retrieved from, <>

9Photo by Coernl. Resized and Changed Format. Pixabay. Retrieved from, <>