How to Clean Solar Panels

15 lightyears has been installing solar panels for both businesses and residential homes in Central Florida since 2012 and during that time, this question has come up a lot for us. For the most part, solar panels are generally self cleaning, but in particularly dry areas or where panel tilt is minimal, dust and other substances can build up over time and impact on the amount electricity generated by a module. Grime and dirt don’t need to cover an entire panel to have an effect. This is where cleaning solar panels may have to be done.

Tips for cleaning solar panels glass

Shut it down
As it’s been said time and time again, safety first so when it comes to shutting down the system before you start, you should follow the procedure in your manual.

Clean solar panels from the ground
While we’re keeping it safe, it’s also wise to clean your panels from the ground if possible. A good quality soft brush and a squeegee with a plastic blade on one side and a cloth covered sponge on the other coupled with a long extension can make for the perfect tools allowing you to stay on the ground. Use a hose with a suitable nozzle to allow the stream of water to reach the panels.

Best time for cleaning solar panels
Clean your solar panels on an overcast day, early in the morning or in the evening. If the sun is beating down on the panels, any water used can quickly evaporate and dirt will become smeared.

Early morning can be a particularly good time for cleaning as dew that has settled on the panels overnight will likely have softened grime. That means you’ll need to use less water and less energy to clean your solar panels.

Materials and methods for cleaning solar panels

If the panels are dry, before tackling the modules with water, brush off any loose materials first.
Don’t use metal objects or harsh abrasive products for removing caked on materials. Scratching the glass on a solar panel can affect its performance as scratches will cast shadows. Avoid using detergents if possible as these may streak the glass of the panel. Use of abrasive powders also risks scratching the panels.

Clean water and a little scrubbing with a coarse cloth covered sponge or soft brush should remove the most stubborn grime.  Plastic scourers may also be used.

Dealing with oily stains

Oily stains can occur in some installation scenarios, such as if you live near an airport and are under a flight path or if you live adjacent to and downwind of a major roadway frequented by trucks. If oily stains start appearing on your panels; isopropyl alcohol can be used as a spot-cleaning substance..

But Do You Really Need to Clean Them?

In most residential installation scenarios,  cleaning solar panels just isn’t worth the bother, unless dirt is clearly visible or performance is noticeably impacted; simply let nature do the job for you – just as it does in creating solar power.