Cleaning Your Solar Panels

December 17, 2020
Posted in Solar Energy
December 17, 2020 Dan

Like any other machine, solar panels need to be routinely cleaned to maintain max efficiency.  In this article, we will cover the biggest questions surrounding solar panel maintenance and when you should start thinking about calling in the professionals.

By not keeping on top of general solar panel maintenance you run the risk of losing panel efficiency.  You could be losing up to the following percentages per quarter, if cleaning isn’t on your agenda:

  • After 3 Months: 5% Energy Loss
  • After 6 Months: 10% Energy Loss
  • After 9 Months: 15% Energy Loss
  • After 12 Months: 20% Energy Loss
  • After 24 Months: 35% Energy Loss

Long story short, not keeping up with general solar panel maintenance costs you money.

Solar Panel Maintenance

How often should I clean my solar panels?

Experts recommend cleaning your system at least twice a year. Doing so keeps your investment in tip-top shape to ensure better efficiency and cost-savings for the future. These systems generally require very little maintenance year round. Areas that receive less rain, however, may require more frequent cleaning.

This will vary depending on the environment you are in.  For example, if you live in Las Vegas, you will most likely need to clean your system more often due to the accumulation of excessive dust and grime.  This would also be the case if you live next to large trees that increase the likelihood of debris or bird droppings falling onto your solar panels.

Note:  Another thing to consider is the angle of your solar panel array.  Flat panels will need more upkeep, as water can pool up and leave a muddy residue when it evaporates.  Angled panels take advantage of rain running across them to clean them.

The Cost of Cleaning Solar Panels

The average spend for cleaning solar panels averages to roughly $150, but can vary based on the roof slant, amount of panels, and height of the house. Business may charge a flat rate that can range between $100 to $35. Some companies charge by panel, which can range from $5-$10 per panel. You may opt to clean your solar panels yourself, but proper equipment is essential.

Pro-Tip: If possible, clean solar panels on level ground if you decide to do it yourself.

When should I clean my solar panels? 

Clean your solar cells on an overcast day, or early in the morning.  If the sun is beating on the panels, any water used can quickly evaporate and dirt will be smeared across the Solar Cells, inadvertently affecting their efficiency, and potentially damaging the panel.  The dew that settles on the panel overnight and into the morning would likely soften any grime that has accumulated on the panels over time, making it an optimal time to clean your solar system.

Solar Blockers

Solar blockers are any obstruction on the panel that deters the path of light. Anything that blocks the lights path to the solar cell will reduce the amount of energy your panels can provide.  Some common solar blockers include dust, leaves, water, and bird droppings. NREL (National Laboratory of Renewable Energy) analysis reports illustrated a potential 30% energy yield loss per year when the solar cells were not cleaned routinely.

Using improper equipment can also add obstruction to your solar panel. Any dust or streaking can cause shadows which will reduce the effectiveness of your panels.

What solar panel cleaning equipment should I use?

A good quality soft brush and a squeegee coupled with an extension pole makes the perfect tool for cleaning your solar system.  For more difficult stains try Isopropyl alcohol or a mild detergent.  Hoses, in most cases, are safe to use on your solar system.

What materials should I avoid?

You want to avoid is scratching the glass on a solar cell.  A scratch on the glass will cast shadows, affecting the overall performance of your panel.

In general, avoid using any type of metals, or harsh abrasive products to help remove debris from your solar system, avoid using detergents if possible, as these can streak the glass solar panel and avoid using high pressure tools that could potentially cause damage.

Clean your solar panels routinely to maintain max efficiency.  Keep in mind the type of environment you live in; if you live in a heavily polluted area, you may need to break out the garden hose more often to clean your panels.

Don’t be a hero, try to keep your feet on the ground unless absolutely necessary.

If something is not budging or you need to clean a whole lot of grime and bird poop off the array, then follow the safety precautions and get up there when it’s a cool day or preferably in the morning.

Use a sponge with a non-abrasive liquid to clean the area gently. Avoid metals, harsh abrasive products, detergents and high-pressure equipment.  Any damage made to the glass will directly affect the efficiency of your solar cell.

Interested in going solar? Check out AES Contact Page for more information!