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A Guide to Cleaning Commercial Solar Panels

By January 13, 2023News
Three solar company workers cleaning solar panels with a water hose and mops on the roof of a commercial building.

Given the soaring energy costs, investing in a commercial solar energy system is a smart move for businesses in California. The cost-saving advantages of solar photovoltaic (PV) panels are becoming more evident each year.

Installing commercial solar panels can help businesses save money on electricity bills. In addition, solar PV systems allow companies to reduce their carbon footprint. After all, they can create clean and sustainable energy.

While commercial solar panels can help reduce your energy costs, they require occasional upkeep for efficient operation. Occasional commercial solar maintenance will ensure your solar photovoltaic system continues to achieve optimal power generation.

Like a well-oiled serviced car, solar panels should not be any different. Continue reading this piece to learn how to clean solar panels to ensure optimal performance and prevent safety hazards.

Do Solar Panels Require Cleaning?

Close up view of man's hand showing dust on a solar panel.

In some parts of the US, accumulated dust and grime on solar panels can cause energy losses of up to 7 percent annually. Although this may not seem like much, it can be a big problem if you want to combat rising fuel prices. Your solar panel technology must be as effective and dependable as possible, even if you frequently need to charge an electric vehicle at home.

Knowing how to clean solar panels is crucial if you consider implementing renewable energy technologies. Commercial photovoltaic installations are frequently outside. As a result of exposure to dust and other pollutants, they gradually become dirty.

Your solar panel system’s performance may suffer if dust and debris are allowed to gather. A well-known form of shade that not only lowers energy output but can also result in hot spots on solar panels is bird poop. Surface detritus means that the amount of solar energy solar cells can absorb is constrained.

It is simple to imagine how different things can soil your commercial solar panels:

  • Dust and bird droppings can block sunlight from reaching the solar cells.
  • Rain can frequently remove the bulk of the buildup off your solar panels. Rainwater may, however, leave behind dirt that lowers performance.
  • Smog and particulate matter can reduce the efficiency of solar panels, especially in densely populated locations with high levels of air pollution.
  • In the fall or during storms, leaves may block your solar panels. The best times of the year to look for leaves are when energy output is at its highest.
  • Heavy pollen can block sunlight from reaching your solar panels.
  • Sea salt can corrode solar panel elements, especially metal ones; additionally, it can enhance the salt accumulation and encourage algae growth.

How Often Should You Clean Solar Panels

Worker cleaning ground-mounted solar panel with a long squeegee.

How often should you clean commercial solar panels is among the most common questions asked by business owners.

Truthfully, one agreed-upon schedule or period to clean commercial solar panels does not exist. The solar panels typically get dirty at different rates, depending on the location/ region. At a minimum, annual solar panel cleaning is ideal.

While planning an interval and setting a cleaning schedule may work for some businesses, it is not the ideal practice. Conversely, you should check your solar panels and look for leaves, grime, dirt, and bird droppings.

That said, most commercial solar photovoltaic systems are built to last. Most of them are between twenty-five and thirty years. Nevertheless, it does not mean you should completely forget about them, expecting the solar panels to “clean themselves.”

Ideally, solar system experts suggest cleaning the panes up to four times annually. Regular cleaning can help ensure your solar panels work efficiently throughout their lifespan. Again, how often you should clean your solar system depends on your exact location. For example, your region may allow you to get away with cleaning the panels twice a year.

However, you may need to clean your commercial solar system more often or occasionally in case of dirt, leaves, and other obstructions on your solar panels. Tracking the energy production of your solar panels using a mobile application may also help determine when it is time to clean your solar panel.

Location Can Complicate the Cleaning Frequency

Three workers cleaning solar panels with water on roof of commercial building.

As mentioned, location can affect your commercial solar panel cleaning schedules.

The location can make cleaning solar panels more difficult. Pollution may be a problem if you reside in a city. The exhaust fumes and other pollutants will be in contact with solar panels close to a busy road.

Even more, pollutants will be present if your business is located in an industrial neighborhood. Regular cleaning is ideal in both scenarios. The issue is not limited to human action. Solar panel surfaces are susceptible to pollen buildup. Monitor the situation from March through May, when tree pollen season typically lasts. Cleaning beneath solar panels is crucial since pollen particles are so tiny.

Consider the effect of wildlife on your solar panels if you live in a rural area. Bird droppings are likely to get on solar panels built close to forests. This might leave a layer of filth that rainfall discharge by itself cannot get rid of.

The Best Ways to Clean Commercial Solar Panels

Closeup view of a squeegee cleaning a solar panel.

Commercial solar photovoltaic system owners should be familiar with the different methods of cleaning solar panels. Here are some tools to help businesses clean their commercial solar panels safely and efficiently.

1. Ground-Level Water Hose

If you wonder about the safest way to clean rooftop commercial solar panels, here is your answer. You can use a ground-level water hose to clean them safely and effectively. Ideally, you want the water spray to fall on the solar panels, so it mimics rainwater. Here, the aim is to let the gravitational forces do the heavy lifting.

2. Isopropyl Alcohol

Do you want to ensure a closer commercial solar panels wash by climbing up the roof? If so, make sure getting on the roof is safe. Then, you can use isopropyl alcohol to remove oily smudges. Isopropyl alcohol ensures zero marks when cleaning smudges.

Soaps and detergents often leave residue on the glass surface of the solar panels. The residue typically attracts more dirt to stick. When cleaning the solar panels, ensure you do not stand on the modules, no matter what. Weight and pressure on commercial solar panels may crack the glass, eventually reducing energy generation.

3. Plastic Scourer and Soft Brushes

When choosing brushes for your commercial solar panels, consider ditching all the other options and opting for those specifically designed for solar panel cleaning. Using these brushes with water can help scrub the panels to remove dirt and grime effectively.

Other scrubbing tools like steel brushes will likely scratch the glass surface of the solar panels. These scratches can harm the energy output.

4. Squeegee

Squeegees to clean solar panels may be used similarly to how you would use them for windows. They help finish the cleaning process, wiping the commercial solar panels dry. Squeegees are excellent for preventing water streaks that would otherwise shade the solar panels.

Top Solar Panels Cleaning Tips

Worker standing behind solar panel cleaning it with a duster.

Knowing a few things is essential before cleaning your commercial solar panels. Let us look at some excellent practical tips for efficient solar panel cleaning.

Read your commercial solar panel’s manufacturer’s manual: Typically, you can clean most solar panels using the same methods. Ideally, you want to see if the manual includes any specific cleaning instructions that you must consider.

Switch Off the System before Beginning the Cleaning Process: You should always switch off your commercial solar photovoltaic system before cleaning the solar panels. You can check the manufacturer’s manual to learn how to shut off the system completely.

Avoid Cleaning Your Commercial Solar Panels in High Temperatures: Exposing solar systems to sudden temperature changes and sweltering conditions can crack the surface glass on the solar panels. Therefore, cleaning the solar panels in the early morning is ideal. Similarly, you can clean them on an overcast day or in the evening.

Disconnect Rainwater Collection Gutters: Disconnecting any rainwater collection gutters before cleaning your commercial solar panels can help prevent water run-off from getting into the collection tanks.

Avoid Using A Pressure Cleaner: A regular garden hose connected to your building tap is fine. However, high-pressure cleaners can damage your commercial solar panels.

Always Call a Professional If Doubtful: If you are unsure about cleaning, avoid taking risks and get in touch with an expert.

Coldwell Solar Offers Solar System Maintenance Services

Reading the above article might have given you an idea of how to clean solar panels. If you are considering installing a commercial solar system, you should know how to clean and maintain the panels for optimum efficiency and power generation.

Do you want to indulge in a lifetime investment for your business while reducing your carbon footprint? Contact Coldwell Solar to go green and save some fortune!


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