Cleaning solar panels is fundamental for anyone who has or will install their photovoltaic panel. To get the maximum energy yield and financial return with your photovoltaic system, you must be up to date with panel maintenance and cleaning.
To help you, I have prepared this complete manual on how to wash the solar panel correctly and safely, ensuring its operation and preserving the panel’s durability. Check out!
Do I need to clean the solar panels?
Yes, cleaning the solar panels is a necessary preventive maintenance to obtain the best performance with the technology, as the accumulation of dirt on the panel’s surface limits the passage of sunlight and reduces the efficiency of the solar cells.
The loss of efficiency in solar panels due to dirt can reach 25% in some cases. The primary sources of dirt on solar panels are dust and soot from urban pollution, which, although they can be eliminated naturally with a good amount of rain, accumulate during dry seasons, especially in regions with low rainfall.
The “poo” droppings of birds and leaves are also other sources of dirt that can impact the efficiency of solar panels, but they are less frequent and common. In extreme cases of dirt on the photovoltaic panel, when the solar panels have never been cleaned, the efficiency loss can reach 30% or more.
How to wash solar panels?
According to the manufacturer’s recommendations, the safest way to wash the solar panel is through specialized companies with trained staff and adequate equipment for the service to avoid damage and preserve the proper functioning, durability, and warranty of the panels. photovoltaics.
Typically, it will also be necessary to climb on the roof to clean the photovoltaic panel, which characterizes work at height and requires technical certification to ensure the safety of those involved.
The leading brands inform in their equipment manuals how to clean the solar panel, including the periodicity, care, and materials that can be used. Therefore, you must read your equipment manual when you buy a solar panel or ask the installer for help to determine how this cleaning should be done.
What is the best time to wash the solar panel?
The best time to clean the solar panels is early morning or late afternoon when the temperature of their surfaces is low, and there is no risk of thermal shocks, which could damage the glass of the modules. Cloudy days are also a good option.
First, it is necessary to turn off the photovoltaic system using the switch in the string box, the initial step in any maintenance of the solar energy generator.
The manufacturer’s guideline is that first, a visual inspection of the solar modules is made to check for cracks, damages, or any loose connection problem between them. So, with everything right, cleaning the photovoltaic panels can be started using the appropriate materials.
What products can be used to clean solar panels?
Generally, the manufacturer’s rule is that cleaning the solar panels is only done with clean running water, which must be thrown from top to bottom in the direction of the inclination of the plates.
If cleaning is carried out when the solar modules are very hot, it is also essential that the water is not cold to avoid thermal shock.
Under no circumstances should products or solutions containing corrosive and alkaline substances be used, such as hydrofluoric acid, acetone, industrial alcohol, etc. It is also necessary to pay attention to the materials/tools used for cleaning the solar panel, which cannot be abrasive and have hard edges, such as blades, knives, and steel wool.
Using these products and materials to clean PV modules can cause scratches or altogether remove the anti-reflective coating layer on your glass surfaces, leading to further dirt buildup and increased loss of efficiency.
In some cases, incorrect cleaning can also cause more severe damage to the plates, such as cracks and microcracks in the solar cells that compromise their operation and can lead to the loss of the equipment warranty.
Another danger is using water-pressurizing machines that are not regulated according to the water pressure supported by the solar panel, which changes for each manufacturer.
While the solar modules of some brands accept 5,000 kPa (50 bar) of maximum water pressure on their glass surface, it must not exceed 690 kPa (6.89 bar) in equipment from other manufacturers.
The ideal is to use a brush or broom made especially for cleaning solar panels, which have an internal hose for the output of water under adequate pressure and soft bristles, in addition to an extension cord that allows you to cover the entire area of the panel without having to step on it about solar panels, something that should never be done!
In the end, it is recommended to dry the photovoltaic panels with a squeegee and a soft cloth to avoid the accumulation of calcium with the evaporation of water.
How often do you need to wash the solar panel?
The manufacturers recommend that the photovoltaic solar panels be cleaned at least once a year, changing to every six months in places with little rain and dust.
However, ideally, you should observe the conditions of the panel yourself and regularly monitor your system’s production through the inverter or solar energy monitoring application.
If the modules are very dirty and your system’s generation has dropped significantly since the last maintenance, it may be time for a new solar panel cleaning.
What are the benefits of cleaning solar panels?
There are several reasons for you to clean your photovoltaic panel, which are:
Guarantees the efficiency of the modules
As already mentioned, the layer of dirt on solar panels blocks the passage of light to their photovoltaic cells, which reduces the panel’s efficiency by 25% and 30%. Therefore, keeping up with cleaning the solar panel ensures that the cells constantly receive more solar radiation and produce as much energy as possible.
Maximize savings and financial return with the system
Maintaining periodic solar panel cleaning also maximizes your financial gains with technology because the system produces more monthly energy. The greater the savings obtained in the electricity bill, the shorter the return on investment in solar energy.
Photovoltaic systems are usually designed to supply the entire electrical consumption of a home or business, resulting in savings of up to 95% on the electricity bill.
When dirt on the panel reduces its production, this savings and monthly financial return also decrease, impacting the payback on the system, which is 4 to 5 years for residential projects today.
Preserves long panel life
Correct cleaning of the solar panel preserves its proper functioning and the long useful life of the technology, which is at least 25 years according to the guarantee of the best solar panel manufacturers but which can be even longer if the equipment receives periodic maintenance.
Prevents defects and loss of warranty
Cleaning the solar panels prevents the accumulation of dirt that can cause defects in the functioning of your cells and which are subject to loss of factory warranty.
How much does it cost to wash solar panels?
The total cost of maintaining the photovoltaic system, which includes cleaning the solar panels, will vary according to each company. Still, the market average is 0.5% of the system’s initial cost. The larger the system, the more expensive the value of its maintenance.
The value may be even lower when the service cleans the photovoltaic panel.
Now you know how to wash solar panels and have learned all the benefits of cleaning the panels and the dangers of when it is done incorrectly. That’s why you need a company specializing in caring for your project to protect your investment and optimize your earnings.