Cleaning solar panels is usually not necessary in the Netherlands. The energy expert says it rains here often enough to wash dirt off the panels. Provided that the panels are placed at an angle of not less than twenty degrees.

However, especially during periods of drought, it’s a good idea to peek at the edge of your roof to see if the panels can be used for cleaning. If the panels were covered with a layer of desert sand, it certainly wouldn’t hurt. “Even with stubborn bird droppings, it’s a good idea to clean up.”

For nearly flat panels, Milieu Centraal recommends cleaning them annually.

If you want to clean the solar panels, it’s best to do it in the spring. “Preferably before the sun starts to shine more and get stronger,” says Stolk. Then you get the most out of your panels. The sun usually shines stronger and more in March. This year it’s a little later. Solar panels generate a lot of energy especially in the spring. Then the sun shines a lot and it’s not too hot yet. Include Heat actually have a lower efficiency.

Due to dirt, panels absorb less light and therefore have lower productivity. According to the energy expert, cleaning will not produce much additional revenue. So the question is whether you will recover the costs of an offshore company. So doing it yourself is the cheapest, provided you can safely access your solar panels.

If the panels need to be cleaned, it is best to do so with some rain water or demineralized water. “Clean it with purified water, because tap water produces tartar,” Stolk says. “This, in turn, leads to lower returns.”

Use a soft cloth or sponge for this. In any case, do not use a high-pressure cleaner or scouring pad. “Then you risk damaging the solar panels.”

Is it hard to reach the panels? Then the solution might be a soft brush with a telescopic handle. “If the boards are on a hard-to-reach surface, I don’t polish them. As soon as it rains, the strongest dirt goes away again.