Whether you already own home solar or are thinking about getting it, you may be wondering: “Does solar panel cleaning make a difference in solar system performance?”
The short answer: yes, cleaning your solar panels helps allow the maximum amount of sunlight to penetrate your solar panels.
More sunlight on your panels = more solar energy = lower utility bill.
In this quick how-to guide, we’ll cover everything you need to know about cleaning solar panels and why regular maintenance is worth it.
Solar panels are durable and built to withstand the elements. Even so, they may accumulate dust, soot or other particulates over time — referred to as PV soiling — which can affect energy production efficiency.
According to the National Renewable Energy Laboratory (NREL), the energy lost each year from solar panel soiling can be as much as 7%, depending on where you are in the U.S.
Consider your surroundings — if you live in Arizona, you may have problems with dust. Coastal California, salt spray. The woods of Massachusetts, leaves and pine needles. If it’s been an active fire season, traces of ash or soot may have accumulated on the tempered glass. These particulates can all affect the efficiency and performance of your solar panels.
How Often Should I Clean My Solar Panels?
Home solar systems are built to last, most for 25-30 years. But that doesn’t mean you can get them installed and assume they’ll clean themselves for the next two decades.
It’s recommended you clean your solar panels up to four times per year to keep them working efficiently throughout their expected lifespan. Depending on your location, you may get away with cleaning them every six months.
With a Sunnova solar system, you can track production using the Sunnova App. If you start to see a consistent dip, this can indicate your panels are ready for cleaning.
How Do I Clean My Solar Panels?
You can clean solar panels on the roof yourself, but since they’re often perched precariously in steep or hard-to-reach spots on the roof, this can pose a safety issue. They also generate electricity, which can also pose a danger.
Here are the different methods you can use to clean your solar panels.
Hire a Solar Panel Cleaning Service
Many companies that install and finance solar panels, Sunnova included, also offer cleaning services. There are also businesses dedicated solely to cleaning rooftop home solar panels. You can also ask a company that normally cleans windows if they can clean your system, but exercise caution when going this route.
In any case, research reliable companies in your area and ask about their processes, rates and experience cleaning solar panels before you decide.
DIY Solar Panel Cleaning
While cleaning your solar panels yourself might seem attractive, it’s not always the best idea. They’re often hard to access safely, and improper cleaning techniques or tools can damage the surface, interfering with efficiency.
Hiring professionals ensures your panels are cleaned safely, thoroughly and without damage, preserving their performance and your investment.
If you want to clean your own solar panels in between professional appointments, here are some recommendations for doing so with water, which can be done safely from the ground without getting on your roof.
- Spray your solar panels with a regular garden hose to tackle light dust and debris
- Avoid harsh cleaning chemicals (and even vinegar), which can cause corrosion
- Refrain from pressure washing, as this can damage the silicone seal
Pro Tip
Don’t clean your panels during the hot, sunny afternoon hours, since the water may dry too fast and leave obstructive streaks. Or worse, the extreme temperature difference between the water and the solar panels may cause the glass to crack. Stick to cleaning them during the cooler morning or evening hours.
The Bottom Line
Do solar panels need to be cleaned regularly? Yes. However, it’s important to know that you don’t need to climb a ladder and scrub them every week — they’re more low-maintenance than that. 2-4 times a year should suffice.
Regular maintenance can improve efficiency and help you reach your system’s payback period faster.
While you can clean solar panels yourself, hiring a professional crew is almost always recommended for safety, quality and thoroughness. Research reliable cleaning companies and ask about their process, rates and experience before you hire.
We want your solar panels to operate to their maximum potential, on a continual basis, year after year. With a little maintenance, you can ensure your system does just that.
Interested in Professional Solar Panel Cleaning?
