How to Clean Solar Panels (& Maintain them) - A Complete Guide

How to Clean Solar Panels (& Maintain them) - A Complete Guide

Solar panels are popular among many homeowners for their ability to reduce or eliminate a home’s dependency on the grid, live a more sustainable existence by reducing their carbon footprint and saving money on their energy bill.

However, you need to be aware that solar panels need cleaning regularly and some maintenance to maintain their full efficiency, energy production and longevity.

If you recently invested in solar panels, whether that be roof mounted panels or otherwise, or are thinking about doing so, it's crucial to familiarize yourself with how to take care of them. While the best solar panels are quite durable, that still doesn't mean they're invincible.

In this article, we will discuss the basics of solar panel cleaning and maintenance to help you make the most of your energy savings.

Why clean solar panels?

Like a car, house windows, or any other item continually exposed to the elements, regular solar panel maintenance involves thorough cleaning.

Over time, grime and other debris can build up on the solar panels and diminish their ability to absorb sunlight and turn it into usable energy.

Solar panels can become covered with dust, pollen, and bird droppings, which reduces their efficiency and power output. In some cases this can cause the entire system to fail. Tests have found that solar panel cleaning can improve panel efficiency by up to 30%.

What you will need to clean solar panels


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As a basic tool kit to clean solar panels, you will need a bucket, hose, spray nozzle, soft brush or non-abrasive sponge and soapy water or specialised cleaning product.

Best practices for cleaning solar panels


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If like many homeowners, you only see your solar panels as objects that sit on your roof and continually provide solar energy without any maintenance needed, unfortunately this is simply not the case.

If you want to maximize their life and keep them in good condition, it's important to know how to clean and maintain them properly.

Here are some basic rules to bear in mind each and every time you clean your dirty solar panels. These are written with your safety and the longevity of your solar panels in mind.

  • Always use proper safety measures when cleaning solar panels on a roof and be sure to use a harness if you are on a sloped or slippery roof.
  • Always do a physical inspection of your solar panels for cracks or damaged wiring prior to starting cleaning, as you don't want to risk having water seep into any of the panels or onto live exposed wires.
  • We don't advise standing on solar panels when attempting to clean them. Even though they are made from sturdy tempered glass, standing on them could be extremely dangerous, especially after the glass surface becomes wet from either adverse weather conditions or cleaning.
  • Never clean your solar panels when they are boiling hot, you risk cracking or shattering them as soon as the cold water touches the surface.
  • It is not advised to spray water directly onto the rear side of your solar panels, as this is where the junction box is located. If you wish to clean this area, simply use a dry or moderately damp cloth.
  • If you are wondering whether it is safe to clean solar panels without turning of the inverter, yes it is fully safe.
  • Avoid harsh chemicals when cleaning the solar panels as this could damage the surface and lead to decreased efficiency.

Basic steps for cleaning solar panels

If you notice after inspecting your solar panels that there is any minor damage, they need to be cleaned as soon as possible to prevent any further problems occurring. If the damage is severe, or you are concerned, always seek professional advice.

Assuming that there are no problematic issues after your visual checks, here are the basic steps for solar panel cleaning:

  1. Be prepared by making sure that you have the tools and equipment suggested earlier before starting.
  2. Remove dirt, dust and debris from the panels by gently brushing them with a soft brush or by using a water hose.
  3. Mix any cleaning solution according to the manufactures instructions and be sure to wear protective gloves and eye wear.
  4. Use a stiff brush to scrub and agitate the surface dirt of the panel with a mild soap or specialist cleaning solution. Be sure to get into all of the difficult to reach areas.
  5. Do a final rinse to remove any remaining solution with clean water from the hose.
  6. Allow the solar panels to naturally dry out for a few hours, or wipe the water off by hand with a soft cloth.
  7. Apply anti-fungal solution, if you deem it necessary.
  8. For extra protection, spray a specialist protective clear coating product or apply a coat of wax to the surface of the solar panels. Once complete allow the panels to air dry for several hours.

Get Rid of Snow and Leaves


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Aside from the regular build-up of dirt and grime, you should also be wary of both snow and leaves residing on your solar panels.

If you avoid cleaning either of these of when they are present, they can block sunlight and reduce your energy absorption significantly.

You can try to remove snow using a leaf blower, but sometimes that alone is not sufficient. You may need to sweep it off by hand with an extendable soft brush or squeegee. The same goes for leaves in autumn.

Another option involves spraying the snow with some warm water (not hot!) to melt the more frozen areas, before removing it with a brush or squeegee as previously mentioned.

Whatever you do though, don't sprinkle it with rock salt, because that could end up causing damage to your solar panels.

What is the Best Time of Day To Clean Solar Panels?

We advise that your solar panels are cleaned either early morning, later in the evening, or when it is a cool overcast day.

If it is a sunny day or the heat from the suns rays are at their peak, the solar panels will obviously become very hot and spraying water onto them could potentially cause micro cracks.

Pouring cold water onto solar panels whilst they are hot can also result in the water quickly evaporating and causing further dirt and grime to accumulate, that will subsequently need cleaning off.

How Often Should I Clean My Solar Panels?

You should do a proper full clean of your solar panels at least once or twice a year. However, you may live in an area where there is a lot of dust particulates or sporadic weather variances, meaning that you may need to do extra less vigorous cleans in between.

The time of year that you should do your cleaning very much depends on the particular area in which you live and the type of climate and seasons that occur.

At times of the year when there is a lot of rain and cloudy weather, the moss growth is a bigger problem, whereas in areas with large amounts of pollen and dryer weather, it’s best to clean the panels during the pollen season, or once it has ended.

How to maintain solar panels


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  • First and most importantly, always make sure that the solar panels are clean. Debris, such as leaves, pollen and general dirt can block the sun's rays and reduce the panel efficiency. Use a soft brush or a garden hose to clean them off regularly.
  • Do monthly visual checks to see if there are any new areas of damage. It is a great way to pick up any issues before they get worse and cause more costly problems down the line.
  • Check the alignment of the panels periodically to make sure that they're facing the optimal direction and angle. Reposition them as necessary.
  • Keep the area around the panels clear of moss, weeds and other obstructions. The panels need to get as much sunlight as possible to be at their most effective.
  • Trim any large trees or branches that might be shading the sunlight from your solar panels.


Keeping your solar panels clean and well maintained is very important for their efficiency and life expectancy.

By cleaning your solar panels regularly, you can extend the life of your whole solar pv system and avoid any potential damage that could reduce their overall performance. This could potentially cost you any maximum savings on your energy bills.

Now that you've learnt how to clean solar panels and maintain them, you can ensure that they continue to run like a charm for many years to come!

If these are jobs that you are unable to do yourself, don't be afraid to hire professionals and get your solar panels cleaned by solar panel cleaning services. You won't then have to even think twice about the maintenance and cleaning chores again.

There's always more to learn when it comes to solar panel cleaning and maintenance, so don't forget to look into more great solar information.