Depending on where you live, electric output from solar panels can be decreased anywhere from 5% to 20% if not regularly cleaned. Dust, dirt, pollen, bird droppings, and even mineral deposits from rainwater can all affect solar panel performance. Experts recommend cleaning panels anywhere from 2 to 6 times per year, depending on the climate, rain, and overall level of dirt and pollen build up on the panels.

Flat solar panels, in particular, are very vulnerable to loss of electric output due to dirt and mineral deposit build-up.  Water can pool on the panels, and without any tilt, dirt and dust, leaves, and other materials can easily build up and create some inefficiencies.

We have researched, tried, and reviewed different products for cleaning solar panels, ranging from brushes and kits, to cleaning solutions.  Here are our choices for the best solar panel cleaning equipment products. All five of these cleaning kits clean solar panels.

Best Choices for Solar Panel Cleaning Equipment

  1. EQUIOMAXX Aquaspray 45 Telescopic Water Fed Pole System (Our Top Pick)
  2. Taishi Solar Panel Window Cleaning Kit
  3. Mr. Longarm 1009 Pro Solar Panel Cleaning Kit
  4. Z-GJRE Water Fed Pole Kit
  5. Equipmaxx Water Fed Pole Kit with Squeegee

1. EQUIPMAXX Aquaspray 45 Telescopic Water Fed Pole System

It is truly the Cadillac of Solar Cleaning Kits. For home or business use, the EQUIOMAXX Aquaspray 45 Telescopic Water Fed Pole System packs a punch with commercial-grade equipment. The water tank is just under 12 gallons, and with 150 feet of tubing,  the unit provides a lot of versatility and room to move while cleaning. It is a battery-powered, wash system on a two-wheel trolley for easy transport.

The unit is very well made, with a steel frame. It comes with a variable water pressure knob to speed up or slow down. The 150 feet of hose is on a reel style base, which allows the user to extend.  For large areas, businesses, or solar panels that require heavy-duty washing, the unit can be wheeled easily from location to location while using.  You can fill the tank with a cleaning solution plus water, or hook the hose up to a direct water source via an adaptor.

You can control the water pressure by a knob on the back of the unit and, at the highest pressure, reaches one gal/min dispersed. With a large range of water pressure, you can use this kit for many different cleaning jobs, not only solar panels. It works well on windows, cars, vinyl siding, storefront signs, etc.

Pros

  • Fully portable on wheels
  • Controlled water pressure
  • 30 foot long water fed pole (also comes in smaller pole sizes)
  • Commercial grade product

Cons

  • 12 gallon tank requires refill for large jobs
  •  Heavier than many other retractable poles
Check the price on Amazon

2. Taishi Solar Panel Window Cleaning Kit

For solar panels that get particularly dirty and require regular cleaning, a power wash cleaning kit can be very handy.

The Taishi Solar Panel Window Cleaning Kit is battery powered and includes a high-pressure pump, which is very effective on flat panels with significant dirt, grime, or bird dropping build up.  The unit has a 30L/7.9 gal water tank with a handle to make it completely portable, and allows for the addition of a cleaning solution to the water for managing dirt and grime.  The hose is pre-threaded inside the pole, which extends to just under 20ft.  The pole itself is lightweight, easy to carry, and made of a high-density aluminum alloy. The cleaning brush is just under a foot long and easily attaches with a gooseneck adaptor.

This unit does a very nice job cleaning solar panels, as well as other glass and windows around your home or business.  The high-pressure water pump makes it a much easier, less labor-intensive task, and the brush is long enough and sturdy enough to scrub the panels easily, yet will not scratch the glass.  The high-pressure pump is very versatile and can be used for other power washing tasks as well.

With a 7.9 gallon tank, for some larger jobs, the unit may need to be refilled during a cleaning session. The tubing can be connected to a garden hose, but would require a trip to the hardware store to get an appropriate adaptor. Also, this unit does not include a squeegee.

Pros

  • Rechargeable battery-powered power washer
  • Professional level cleaning
  • Top quality, versatile, many uses

Cons

  • Limited amount of water
  • No squeegee attachments, or hose adaptor included
Check the price on Amazon

3. Mr. Longarm 1009 Pro Curve Solar Panel Cleaning Kit

It is a very thorough cleaning kit. The Mr. Longarm 1009 Pro Solar Panel Cleaning Kit comes with both 18″ and 22″ wash bars, wash sleeves, and squeegees. It also comes with an extension pole that extends from 5-12 feet. A flow-thru wash pole that extends from 4-8 feet, a flow-thru cleaning brush, and flow-thru angled adaptor are also part of the kit. Accessories like two tool handles, a microfiber towel, a cleaning guide, and a canvas carrying case for easy storage and transport come with the kit for no extra charge.

This unit is well made and provides everything needed to clean, wash, and buff Solar Panels. With several options for cleaning, either the flow-thru tools, which hook up to a garden hose, or you use the standard cleaning tools with traditional cleaning solutions, the kit is very versatile. Mr. Longarm also sells other accessories separately that are compatible with this unit as well.

The biggest issue we have found with this kit is the pole lengths. At their longest extension, and if a longer pole is needed, it must be purchased through Mr. Longarm separately.  The brushes, squeegees and wash bars at 18″ and 22″, which does cleaning much faster than with a 12-inch brush that is standard with most setups from competing manufacturers.

Pros

  • Versatile kit, useful for various cleaning tasks
  • Brushes and squeegees are well sized
  • On/Off water switch right on pole

Cons

  • Pole lengths are limited
Check the price on Amazon

4. Z-GJRE Water Fed Pole Kit

The Z-GJRE Water Fed Pole Kit comes in 4 different lengths from 12 to 30 feet in length, depending on the location and size of the panels or window. The kit includes an adaptor to reach tough angles, and the pole has three sets of locking mechanisms to customize the length of the pole as needed while washing.

The kit also includes a gooseneck adaptor for the brush, a brass adaptor to hook up to a water source, and a three-way split joint. The brush is almost 24 inches long, which makes washing large panels much easier than the foot-long brushes. The pole itself is lightweight aluminum, and, rather than extending to 1 or 2 different lengths, it can be used at any length from standard size to fully extended.

Pros

  • Lightweight professional grade aluminum, good build quality
  • Available in 4 sizes
  • Fully versatile sizing with locking mechanisms
  • Large brush handles panels easily

Cons

  • No squeegee included
  • One size brush only, maybe too large from some panel types
Check the price on Amazon

5. EQUIPMAXX Water Fed Pole Kit with Squeegee

Kits like the Equipmaxx Water Fed Pole Kit with Squeegee are a great choice for cleaning solar panels because they hook the cleaning tools right to a garden hose or other water source. It’s ideal for cleaning requiring roof access via a ladder or heavy-duty cleaning where a high volume of water is necessary. Having an unlimited source of water streamlines the process, and is much safer than carrying buckets of water up and down a ladder.

The Equipmaxx tool is approximately 7 feet long, but extends to 24 feet in length. It is lightweight aluminum, which keeps the overall weight of the tool down to a very manageable 6 pounds. The pole has a double gooseneck adaptor, which allows the user to place the cleaning brush on one side and a squeegee on the other for convenience. Inside the tool handle, tubing runs the length of the unit and attaches to your garden hose and includes a shut-off valve to control the flow water. The kit includes an adaptor to attach the tubing to the hose.

The brush and the squeegee are of decent quality. Still, since the unit hooks up directly to the hose, there is no way to add a cleaning solution to the water itself. For heavily soiled panels, users may need to apply a cleanser directly to the panels before using the tool.

Pros

  • Very lightweight and easy to manage
  • Connects directly to hose for easy water source
  • Extends to 24 feet

Cons

  • Cleaning solution must be used separately
  • Tubing can bunch when retracting
Check the price on Amazon

Solar Panel Cleaning Kit Buyers Guide

Several things are important to consider when buying a Solar Panel Cleaning Kit. You want to consider the size and location of your panels, how often they require cleaning, your water quality, and the type of debris on your panels.   It is also important to understand exactly how to clean Solar Panels, so they don’t damage during the cleaning process.

Size and Location

When deciding on cleaning equipment, you need to consider the size of your panels and the location.  For rooftop solar panels, you want to ensure that you are using lightweight materials that you can easily transport to the roof and use without putting yourself in physical danger.  You need to consider the length of the tubing, and perhaps get a kit that attaches to a separate water source, such as your hose.  That provides a little extra flexibility regarding positioning, and you won’t need to make multiple trips to refill a water bucket or cleaning tank.

With ground-mounted solar panel systems, you have fewer safety concerns and more options for cleaning. If you prefer a system that includes a water tank, where you can mix the cleaning solution with water, you can use a fully portable system, and not have to worry about maintaining contact or staying nearby from your water source.

Consider the size of your panels when selecting brushes. While most kits contain 12-inch brushes, for larger panels, you may want to consider either buying a kit with wider brushes or contacting the manufacturer to see if they have brushes that will work with your unit that are separate accessories.

How Often Do Your Panels Require Cleaning?

Depending on how dirty your panels are, the size of your system, and how much energy you generate, cleaning requirements can vary greatly. With less than 10% loss, most people don’t see a huge difference in efficiency. For some households or businesses, dirty panels can reduce the amount of energy generated as much as 20%. A good rule of thumb is, at a minimum, clean your solar panels twice a year for maximum efficiency.

Flat panels typically require cleaning more often, simply because dirt gets stuck on the panel with no easy way to get off without cleaning.  Any tilt of your solar panels will aid in removing some of the dirt that gets onto the panels. The angle at which your panels sit will make a difference in the cleaning schedule.

Your location also plays a large factor in how often your panels require cleaning.  If you are in a city or an industrial area where smog and dust and dirt can accumulate rapidly, you will need to clean more often—areas where trees and birds in abundance can also create the need to clean more often as well. Bird droppings can wreak havoc on the overall efficiency of solar panels in areas where birds are plentiful.

For solar panels that require frequent cleaning, investing in a system that includes a tank for cleaning solutions may be the best option for you, as a water-only cleaning may not clean the panels as well as necessary to ensure that they operate at peak efficiency.  You can also invest in a kit that attaches to a direct water source and purchase separate cleaning solutions to use in tandem with the flow-through style brush attached to your hose.

Weather

Weather, snow, rain, falling leaves, and other factors, including climate,  also contribute to the amount of dirt and grime that will attach to your panels. For households and businesses near the ocean, for example, can see large drops inefficiency, or high soiling losses from their solar panels due to the amount of saltwater in the air.  Houses in these areas are also more prone to corrosion. Though most solar panels that are in areas near saltwater are tested and treated to be corrosion resistant, it is still a good practice to maintain a regular cleaning schedule to ensure that your panels stay as salt-free as possible.

Frequently Asked Questions

When is the best time to clean solar panels?

You will need to shut down your solar panel system to clean the panels.  Since they generate a lot of heat, it can be hazardous to do any cleaning or maintenance on your solar panels during the heat of the day.  The best time to clean your solar panels is in the early morning hours. Once it is light enough outside that you could drive your car safely without using headlights, it is light enough for you to access your roof safely, if necessary, or otherwise clean your solar panels.  If your roof, or the area around your solar panels is damp from rain or other weather events, do not risk cleaning if the area is slippery.  Pick a dry, cool morning to clean your solar panels.

If mornings are not an option for you in terms of cleaning, the next best choice is cleaning your solar panels on a cloudy day.  Ideally, the mid-day hours are still not the best choice of times, even on an overcast day, but late afternoon, or early evening, before sunset on a cloudy day is also an option if mornings do not work for you.

What is the best method for cleaning solar panels?

Always check with your solar panel manufacturer to see if they have any specific instructions that are unique to your unit.  Otherwise, the process is very simple. First, you want to use a soft brush, cloth, or soft broom to wipe off any obvious debris, loose dirt, or leaves. For flat panels, you will want to ensure nothing sticks in the corners of your panels. Once you remove all loose debris from your panels, you can start cleaning.

Depending on exactly how dirty your panels are, you can choose to do a water wash only, or use a mild detergent to clean the panels. There are specific solutions that you can purchase to clean solar panels. Here are two popular examples of cleaning solutions:

WINSOL Solar Brite Cleaning Solution

Solar Brite is a biodegradable, nonhazardous cleaning solution that contains no phosphates, no heavy metals, and no chlorine. It cleans grease, oil, fuel oil, hard water stains, bird droppings, and other common solar panel build-ups.

Check the price on Amazon

POLYWATER Solar Panel Wash

Polywater is a nonabrasive, biodegradable, solvent-free cleaning solution designed specifically for use on solar panels.

Check the price on Amazon

Most of the solar panels cleaners on the market are to clean everything, including hard water residue from your panels, and aid in maximizing the efficiency of your panels. It is important to use biodegradable solutions since the cleaning solution will come in contact with grass and ground and, ultimately, groundwater. Therefore, it is important to get cleaning solutions that are to clean solar panels or a similar window/glass cleaner.

Once you have used a cleanser on your panels, rinse thoroughly and always squeegee the remaining water off of the solar panels.  Getting the remaining water off the panels is most important in areas where hard water exists.  Hard water build-up can dramatically impact how well your panels work, and how much soiling loss you experience.

Can I use cold water to clean my solar panels?

Ideally, you should be using tepid or cool water, not cold water, to clean your solar panels. Several manufacturers of solar panels have advised that, in some cases, cold water on very hot panels can cause cracks or breakage.  Using water from your hose should not be damaging to your solar panels.

What is most important to remember when cleaning your solar panels is not to use any metal objects to clear away or scrape dirt and debris from the glass. Harsh chemicals and abrasives can cause small pits, scratches, or other damage to your solar panels, which could reduce overall efficiency and output.

If your panels are located on your roof, and you cannot access them safely, you may want to consider hiring professional cleaners to handle the periodic cleaning of your solar panels.