Dust, dirt, and grime building up on your solar panels? Even in a rainy location like East Hawai’i, rainwater is not enough to keep my solar panels clean. They regularly get caked in dirty grime, even with 150” of rain per year.
To clean your solar panels, you’ll need to soak your panels with water to loosen the grime, scrub it down with a good brush with a long handle using soapy water, then rinse the panels off with clean water. Depending on where your panels are located, you may also need a ladder to access them.
You can save a lot of money by doing it yourself instead of hiring professionals. You do need to use caution though. Solar panels are delicate and can be easily scratched without proper care. Here’s how you can clean your solar panels without hurting you or your power investment.
Related: I have tried out a few different methods for cleaning my solar panels over the years and the best tool that I could find to get the job done was a simple RV brush. I have shared a link to the one I’ve used to clean my panels. I have had the same one for over 5 years now and it barely cost anything to purchase.
Do You Need To Clean Your Solar Panels?
The short answer is, yes. Rain is not sufficient enough to clean off your solar panels. If I have to clean mine, in one of the rainiest locations on earth, you are going to have to clean yours too.
I live in what some consider the cleanest air on earth, but still, the panels cake up in dirt and need to be cleaned about 1 to 2 times per year. Some locations are prone to dirtier conditions, requiring you to wash your panels monthly for them to perform optimally.
Here are some situations that will make your panels dirty.
- Irregular rain.
- Industrial smog or wildfire smoke.
- Tall trees in the area.
- Many birds in the area.
- High pollen season.
- Overly humid climate.
- Live near the ocean.
- Living near a highway, airport, or farm.
- Solar panels lie flat or almost flat.
- You’ve had solar panels for over a year.
If your solar panels are dirty, their efficiency can be significantly reduced. Furthermore, the build-up can mess with the electrical technology causing problems in the future.
When to Hire the Experts
When in doubt, hire a specialist to have a look before cleaning your panels. A specialist will let you know if your solar panels need to be cleaned or if other issues need to be addressed first.
If you don’t want the hassle of buying safe cleaning supplies, don’t own a ladder, or have complex or dangerous roof construction, it’s best to hire professional cleaners to do the job of cleaning.
You don’t want to risk damaging the panels or hurting yourself if you’re unsure or feel unsafe.
When to Clean Your Solar Panels
That being said, if you’re physically able to and the panels aren’t too dirty, you should be able to do everything yourself.
Schedule a day in the cooler months for cleaning your solar panels or you can do it in the early morning or late afternoon hours on hotter days.
Solar Panels can get hot during the day. If you clean your solar panels when they’re hot, the water will evaporate too fast, creating a film that will need to be cleaned off.
This is why we choose times that are cooler for cleaning our panels. Not only will this limit you from getting hurt but will also prevent the panels from getting damaged as well.
Basic Materials Needed For Cleaning Solar Panles
- A garden hose with a garden nozzle.
- Solar-panel-safe soap or cleaner.
- Soft, solar-panel-safe scrubber.
- A stable ladder.
A Brief How-To On Cleaning Solar Panels
- Lightly hose off the panels using your garden hose. Complete this step from the ground, a ladder, or the roof (see down below).
- Use a soft scrubber soaked in a bucket of soapy water to gently clean the panels. Alternatively, use a spray bottle with solar panel-safe cleaner instead of a bucket of soapy water.
- Rinse off the soap/cleaner with the hose.
- Squeegee excess water until the panels are dry.
- Repeat for all surfaces of the panels.
- Clean the entire surface of the solar panel. Even if part of it looks clean, the shadows may be preventing you from seeing dirt.
- Focus on the bottom edges of the solar panel. These will be the dirtiest.
Different Methods For Cleaning Solar Panels
Depending on your situation, you have a few ways to clean your solar panels. Starting from most basic to most intricate, here are three different ways to keep your panels sparkling.
Easiest: From the Ground
If you want to give your solar panels a quick clean, the easiest and safest method is from the ground. In most instances, the most cleaning you’ll ever need to do is a simple hosing down.
Cleaning from the ground might work for you if:
- You believe the dirt is just a light layer of dust.
- Your roof is low to the ground.
- Your hose can spray onto the roof of your house.
- You don’t think you’ll need to use a pressure washer or high-pressure hose attachment to get the job done.
Can You Use A Pressure Washer To Clean Your Solar Panels?
Using a pressure washer is not advised for cleaning solar panels. High pressure can damage the energy output of your solar panels. It is recommended to only use a scrub brush for cleaning solar panels.
If you absolutely must use a pressure washer to reach the roof, set it on the lowest pressure setting and be extremely careful not to directly spray the panels. The high pressure can easily create small scratches on the dirty surface of your solar panels. It is these tiny scratches that can permanently damage the energy output of your solar panels.
Generally, if you feel you need to use a pressure washer to clean off the solar panels, you should use the ladder or roof method instead.
Heavy Build-up: A Ladder
You can combine the hose with a squeegee if you feel your solar panels need some extra TLC.
Using a ladder might work for you if:
- Your roof is higher up than a hose can reach.
- Your solar panels need to be scrubbed down.
- You have a dependable and stable ladder available.
- Bucket of soapy water or a solar-panel safe cleaner
- Long handle squeegee
- A stable ladder
- A harness (optional)
Expert Level: From the Roof
It’s best to save heavy-duty cleaning from the roof for the experts. If you have sufficient training, then you can clean the solar panels from the roof yourself.
Cleaning from the roof might work for you if:
- Your panels are positioned far enough from the edge that you can maneuver around them safely.
- The solar panels need careful, close cleaning (more than a spray down).
- Your roofing is made of sturdy material.
- Your roof isn’t too steep.
- You have experience working on roofs.
- All the material listed previously.
- A safety harness.