DIY manual cleaning of solar panels is not only time-consuming, it also puts solar panel owners at risk on their roof. Even if you hire a professional to clean your solar panels for you, that requires additional expenses to pay a contractor.
For owners who are tired of dealing with the hassle of cleaning solar PV panels, there is a third option: solar panel cleaning robots. These robotic cleaners are a handy new technological equipment that provide a solution for the cleaning process. But how do solar panel cleaning robots work?
These autonomous robots are operated by remote control. They are a solar panel cleaning system that provides an efficient solution to washing dirt and grime off your solar panels. Cleaning robots are especially great for large commercial solar arrays or solar farms.
What is a Solar Panel Cleaning Robot?
Solar power supplies 2.8% of America’s energy. Known for its sustainability, solar energy is beneficial to the environment because it provides a renewable source of clean energy and reduces your carbon footprint.
But to keep solar panels running efficiently, solar panels must be kept clean, as dirt and grime collected on the surface of a panel slows down its productivity. Accumulated dirt and grime blocks the solar cells from absorbing sunlight and converting it into electricity.
To prevent soiling, an autonomous robot cleaner washes your solar panels for you. Cleaning robots are usually operated by remote control. They clean both rooftop and ground-mounted solar panels.
Solar panel cleaning robots are boxy in shape, a square rectangle on treads. They have a giant brush placed on the both front and the back ends of the robotic vehicle. Their main components are:
- Treads or wheels
- Roller brushes
- Water tank
- Water sprayer
- Motor
- Battery
Solar panel cleaning robots are most often used for commercial solar arrays or solar farms. They are very expensive, so they may not be practical for residential properties.
How Does a Solar Panel Cleaning Robot Work?
How a solar panel cleaning robot works depends on the model and type. Some robots wash panels with water, while others are waterless cleaning robots that use spinning brushes to wipe off grime.
With this robotic technology, solar panel cleaning robots can even clean a solar array daily. The robots are designed to operate all day so that they can clean a large number of solar panels on a regular basis. However, if the cleaning robots are a type that uses water, running them daily will require a lot of water usage.
Solar panel cleaning robots usually move at speeds of 30 to 40 meters per minute.
Most robots use water to clean, and the cleaning robot is supplied with water from water tanks or water pipes.
- Water pipes are hoses that attach to the top of the robots. They pump water to the cleaning robot as it works. Water pipes can be attached to a regular water hose connection or a water truck.
- Water tanks are situated on top of the body of the robot, where they can be refilled by pouring water into the opening on top.
The robot will spray down the panels with water and then scrub them with a brush as it drives over the panels. Sensors allow the robots to determine their route and detect the edge of the roof. That way a solar robot will never drive right off a panel.
Components of Cleaning Robots and What They Do
There are several components to a solar panel cleaning robot:
- Roller brushes. Cleaning robots are equipped with soft specialized brushes, perfect for cleaning off dirt buildup without scratching the panels.
- Wheels or treads. Robots use rubber caterpillar tracks or polyurethane wheels to stick to the glass surface while the robots clean the solar modules. They can stick on panels set at angles up to 45 degrees.
- DC coreless motors. Both the roller brush and the wheels are rotated by a DC motor. Typically, automatic cleaning robots are powered by coreless DC motors. By necessity, the motors must be lightweight so as to not damage the solar panel’s surface.
- Water sprayer. The robots spray down the panels with water and then scrub them clean with the roller brush. The sprayer is connected to a water tank or water pipe.
- Water pipe. To supply cleaning robots with water, a water pipe pumps water from a regular hose connection or from a water truck to the cleaning robot.
- Remote control. Cleaning robots are operated by a wireless remote or an app.
- Control system. The control system transmits instructions and commands to the power system. It’s what moves the robot according to the signals it receives from its remote control.
- Power system. The power system controls the direction and speed of the robot’s movements.
- Electric power system. The electric power system is what powers the whole operation by providing electricity so the solar panel cleaning robot is able to move.
- Sensor. Sensors allow solar cleaning robots to move in grid-like patterns and in straight lines up and down the panel. Sensors allow robots to detect the edge of the panel so that they will automatically stop before driving over the edge of a panel.
- Battery. Even solar panel cleaning robots are powered by solar, since the robots are usually equipped with their own mini solar panels mounted on top, which creates solar energy to power the solar robot. The battery recharges automatically whenever the device is low on power.
Some solar panels are designed to collect rainwater and reuse it as cleaning water. Being powered by solar energy and collecting its own rainwater makes it a self-sufficient device.
How Waterless Cleaning Robots Work
In dry areas that face drought, using water to clean solar panels might not be possible. To accommodate the desert regions, cleaning robots have been designed to clean panels without using water.
Instead, a swivel brush spins rapidly in circles as it passes over the panels. The rapid movement knocks all the dirt off, no water required.
Cleaning with water will always be the most effective way to thoroughly clean solar panels, but waterless models are more practical and environmentally friendly, as they get the job done without wasting water.
Benefits of Solar Panel Cleaning Robots
Although solar panel cleaning robots are expensive, they have both environmental and financial benefits. They save on time, money, resources, and labor. They provide a safer and more efficient method of cleaning a solar panel system.
Eliminates Chance of Injury
With cleaning robots, no one has to get up on the roof to clean the panels. While some solar panels are installed at ground level, in many cases solar panels are placed in high spots such as rooftops. Being in places that are difficult to reach safely makes them difficult to clean.
With automatic cleaning robots, no one has to get up on the roof, which eliminates the risk of falling off a roof or ladder.
Daily Cleaning
With cleaning robots, you can clean your solar panels daily. Because they are exposed to the outdoor elements, solar panels get dirty easily. The dirtier they get, the more energy production slows down because grime obstructs the photovoltaic cells, preventing them from efficiently absorbing sunlight.
Daily cleanings will greatly bolster their energy output. Panels that are kept clean also last longer and are less susceptible to damage, which in turn reduces maintenance and repair costs.
Saves Money
Owning an automatic cleaning robot means that owners don’t have to worry about hiring a solar panel cleaning company to do the job for them.
Solar panel cleaning robots eliminate cleaning service costs. Because the solar modules can be cleaned more frequently with a robot than manually, they will produce more energy, which saves money in the long run.
Saves Time
Solar farms benefit greatly from solar panel cleaning robots, as these cleaning systems quickly wipe down multiple dirty panels at a time.
Manually cleaning solar panels is much slower than cleaning them with robots, so having an automatic cleaning system is an essential time-saver for large-scale solar arrays.
Good for Hot Environments
Hot climates tend to have more dust and dirt in the air, conditions that cause solar panels to get dirty more quickly. As a result, solar panels in dusty, dry areas need to be cleaned more frequently to continue producing efficiently.
In dry environments, waterless cleaning robots are a practical cleaning solution.
Because solar cleaning robots are automatic, they clean dirty panels on a daily basis to keep the pesky dust at bay. And in dry environments, waterless cleaning robots are a practical cleaning solution.
Eco-Friendly
Fossil fuels are a limited resource that is predicted to run out by 2060. Solar power is a renewable energy source, since there will always be more sunlight for panels to absorb and convert into energy.
Rather than relying on gas and electricity, solar panel cleaning robots save on fossil fuels by using solar energy to operate instead. Waterless cleaning robots additionally conserve water, which in turn helps protect the environment.
Why Should I Clean My Solar Panels?
Cleaning solar panels sounds like a hassle, so you may be wondering if it is even worth it.
There are several reasons why solar panels need to be cleaned:
- Increased energy efficiency. Grime blocks the solar cells from absorbing sunlight, slowing down productivity. When dirty, a solar panel’s energy output rate can decrease by 10% to 30%.
- Extended lifespan. Dirt sitting on a solar panel can shorten its lifespan, reduce its durability, and decrease its energy output. Keeping your solar panels grime-free helps your solar panel last their full lifespan of 30 years.
- Improves ROI time. If you keep your solar panels clean, they can produce the energy needed each month to save you on your energy bills. The more you save, the quicker the panels will pay for themselves.
- Warranty conditions. Some warranties require solar panels be regularly cleaned, otherwise the company will not honor the warranty agreement.
- Improved curb appeal. Panels covered in dirt aren’t appealing to look at. Cleaning them regularly will keep them looking shiny and new.
- Prevents hot spots. Hot spots occur when a section of the panel overheats due to too much dust and debris on their surface. Hot spots damage panels and decrease their lifespan.
You can use a monitoring app to check on your solar panels’ performance. If you notice a drop in their energy output, it might be an indication they need cleaning.
There are several benefits to cleaning solar panels, so it’s important to schedule regular cleanings for your solar system. It is recommended that owners have their solar panels cleaned once or twice a year.
Cost of Solar Panel Cleaning Robots
After investing in solar panels, you might not want to shell out the extra money for a solar panel cleaning robot. Cleaning robots are expensive, usually costing around $3,000. Robots are not cheap, but they are beneficial and help solar panel owners save money on energy bills.
Drones as a Way to Clean Solar Panels
Another neat new way of getting your solar panels squeaky clean is to use an aerial drone. With drones, you can spray down a dirty module with soapy water to rinse them off.
Since they spray a cleaning solution while hovering over your solar panels, they don’t have the capability to scrub down panels. While hosing the panels down with water removes most of the dust and debris, it won’t be effective against any gunk that requires scrubbing to get it off.
The downside of drones is that due to low battery storage, they quickly run out of battery power.
Drones can additionally be used to drop off autonomous robots by dropping them off on the solar panels. A drone will carry them directly to the panels, and from there the robot can set to work cleaning your solar array. This is especially useful for reaching high places that would be difficult for solar panel owners to reach otherwise.
FAQs About Solar Panel Cleaning Robots
No, solar panels should be safe while robots are cleaning them. Solar panel cleaning robots use wheels or treads specially designed to protect the glass surface of the modules.
Rain helps wash off some of the dirt and dust on solar panels, but it won’t give solar panels a thorough cleaning. Solar panels should be cleaned at least one to two times a year, since rain won’t be enough to wash them.
Although solar panels are durable and resistant to rough weather, they can be cracked by hail or other falling objects.
The Future of Solar Panel Cleaning
Although robotic cleaning technology is new and still in its early stages, it is a helpful piece of equipment for those with a large number of solar arrays, providing an efficient, low-effort method for quickly cleaning solar panels. Best of all, owning a cleaning robot makes it easy to give your panels regular cleanings on a daily basis.
If you are looking to hire a professional cleaner who can clean your rooftop solar array, don’t hesitate to find the right contractor for the job.
Main Image Credit: Alex Butterfield / Flickr / CC BY 2.0
