How to clean your solar panels?

Photovoltaic solar panels do not require much maintenance. Covered with a self-cleaning and robust protective film (since they do not contain any mechanical elements), they do not require frequent washing because the rain takes care of them. However, manufacturers still recommend that solar panels be cleaned once a year or twice a year, especially in areas with high air pollution or low rainfall. Here is the procedure to clean your photovoltaic roof without any risk…

When to clean the solar panels?

Cleaning a solar panel is recommended:

– In the spring to remove the dirt accumulated during the winter;

– In the fall if your roof does not have a steep slope, it does not rain much in your area and if your environment is conducive to soiling.

However, this cleaning before the winter period is mandatory if your home is close to factories, if it is located in the countryside near farms (harvesting, spreading and ploughing produce a lot of dust), if it is by the sea (the spray leaves salt on the panels and the sand and the droppings of the seagulls are also very dangerous), or if your home is in an urban environment (with heavy vehicle traffic);

– In winter when it can be useful in case of snowfall. Indeed, the latter hides the solar cells and prevents the panel from producing energy properly. The winter season still has sunny days, so it would be a shame not to remove the snow and have a considerable loss of income.

It should be noted that a clogged solar panel can have its efficiency reduced by 15% per year. The cleaner the solar panels are, the better they work at 100% of their capacity and the more electricity and hot water they produce. The installation is then amortized more quickly and the energy debt is reduced accordingly.

Precautions to be taken and actions to avoid

When you go to clean your photovoltaic panels, do not:

– walking on it because it can cause microcracks and you could slip and injure yourself;

– throw ice or very cold water on it, especially when it is very hot and the sun hits the glass (the thermal shock generated could damage the solar cells);

– use a device that sprays water at high pressure (such as a karcher) because it would damage the joints around the panel;

– scratch or rub the glass too hard in case of stubborn soiling as this may scratch it (for this purpose, it is advisable to use a foam scraper rather than a plastic one or to choose a scraper with a wetting agent);

– use hard water because limestone can leave white traces that will interfere with the proper functioning of photovoltaic cells. Use demineralized or softened water;

– use detergents because they are too abrasive. Water alone is enough.

In addition, if your squeegee does not have a long enough handle, you can use a telescopic pole (7, 9 or 11 meters) generally sold in a photovoltaic panel cleaning kit with a corresponding hydro hose, elbow and soft brush for solar panels.

How to clean photovoltaic panels?

To clean your solar panels (preferably in the morning or at the end of the day), you must first climb on your roof, taking all the necessary precautions. But the best way is to use a telescopic pole (suitable for heights up to 15 meters) that allows you to stay with your feet on the ground and not take any real risks.

Clear, temperate or warm (preferably demineralized) water should be sprayed on each panel.

Then, you must pass the squeegee over the glass, without scratching and with a single movement, to remove dirt and all traces of water.

However, if your roof is very sloping, difficult to access or you are afraid of damaging your panels, it is best to call your installer who can take care of the annual or semi-annual maintenance of your photovoltaic panels. You can also use a company that specializes in cleaning solar panels.

The advantage is that the professional will be able to check at the same time that your solar panels do not have any particular problem or failure (especially with regard to the inverter that protects the installation, disconnects it in the event of an anomaly in the electrical network and allows you to monitor the daily performance of the panel).