Do I need to Clean my Solar Panels?

Do I really need to clean my solar panels to keep max efficiency?

It's a question that our Service Department here at Cosmic Solar receives every single day. Do really need to keep my solar panels clean? And what's the net effect of not cleaning them versus keeping them squeaky clean? And how should I approach cleaning? All great questions.

For starters, we don't necessarily recommend frequently cleanings (more than once a year or every other year) for most roof mounted solar panels. Reason being is they are up off the ground, typically have a decent roof pitch to keep dust and dirt off of them and don't accumulate so much dirt or dust that it would be a huge detriment to solar energy production over time. You probably have more important things to do with your time -- like spending time with your family,  learning a hobby and cleaning out the garage. Most houses fall into the category where they could get by with a thorough solar panel cleaning every few years and everything is fine. Occasional rain may be enough for most Southern California homes to keep their solar system efficiency relatively close to peak without frequent washings.

However there are some situations, like lower sloped or flat roofs, ground mounted systems, houses that have horses or goats that run around frequently, kicking up dirt, or other situations where there are a lot of trees around that can drop sticky leaves. We've even seen bird nesting grounds where bird droppings frequently make it on the panels and effective cause "shading" of the solar cells, reducing solar panel energy production. Most systems with these types of situations can see a 10-30% drop in production if things get REALLY bad, but even then, the efficiency of a solar panel to collect light and produce energy is still quite impressive.

If you have a situation at your home or business where the solar panels are prone to getting dirtier than a typical home for various reasons, you may want to consider having them cleaned once a year or more frequently depending on your individual situation. There are many ways to clean your solar panels, some ranging from just sprinkling water on them to setting up a comprehensive cleaning system with deionized water. No one way of cleaning your solar panels is wrong, though, in our opinion, some methods don't get the panels clean enough to move the needle and others simply cost too much, take too much time or provide only a marginal benefit to their methods.

To keep things simple, yet very effective, we recommend treating your solar panels in a similar fashion to how you would wash your car. Use water from the hose, soap, a very soft, non-abrasive brush to get more than just surface dirt off -- and a squeegee on a telescoping pole, if necessary, to remove excess water. We have a quick example of how you can keep your system clean here: How to keep your solar panels clean!

With that said, if you have a roof that is difficult to access, a roof surface such as fragile tile or aluminum, are afraid of heights or otherwise just do not have the skills or know how to walk on a roof, we recommend hiring a company to come out to clean your solar panels. Here at Cosmic Solar, our Service Department is standing ready to provide a quote for your individual home and situation. If you would like to speak to someone about cleaning your solar panels and you live within our service area, we're happy to help! Simply contact our Service Department at 760-749-1111.

If you're the adventurous type with the knowledge and abilities to clean your own solar panels, more power to you. Literally. Stay safe out there on your roof and happy cleaning!