Do you have solar panels, or are you considering installing some? Solar panels can be great for the environment and will save you money on your electric bill over time. But did you know that they needed to be cleaned regularly to keep them working their best?
You have to clean your solar panels – a couple of times a year usually – to make sure they are working as efficiently as possible. Here’s what you need to know.
Consider the types of solar panels
Do you have flat solar panels or are they slanted? The answer will tell you how often you need to think about cleaning them.
Slanted panels tend to stay clean easier, especially if you get rain often. You might only need to clean them once a year.
Cleaning is much more important for flat panels because rain water doesn’t run off the way it does with slanted panels. Dirt and debris tend to pile up more on flat panels. Depending on your weather and the location of your panels, you will need to clean 2-4 times a year.
Why clean solar panels?
It’s no surprise that solar panels need sunlight to work correctly. If the sun is obstructed by dirt, then the panels produce less power. The more dirt, the more of an impact.
Google actually did some research on their own solar panels and found that the energy doubled overnight after cleaning flat panels that had been in use for a little over a year.
Your solar panels may need to be cleaned because of:
- Dirt and Dust (especially in desert areas or near farms)
- Bird droppings
- Organic Debris
Rain usually takes care of slanted panels, but over time some debris may still accumulate in the corners and edges. And relying on just rain may not be enough forever. Think about other outdoor items like your patio furniture – it still looks dirty even though it gets rained on, right? Make sure you schedule some time to do a thorough cleaning no matter what type of solar panel you have.
Track your progress
Keep track of your energy output before and after cleaning – this will show you the impact regular cleaning can have on your solar panels! Over time, you will learn the patterns and this data can give you insight into when it’s time to clean.
Let’s say you think you need to clean every 4 but after a couple of times, you notice that your efficiency doesn’t start to dip until closer to 6 months. Now you can adjust your cleaning schedule to save time and money!
When to clean solar panels
If you are cleaning your panels only once a year, spring is probably the best time. This is because there are more dust and pollution in the air during the winter. Wash that all away in the spring and you’ll be set for the rest of the year!
Are any of the following true for you? If so, you probably need to clean your panels twice a year.
✓ flat panels
✓ sunny climate
✓ panels located near a farm or field (plan to clean after harvesting is done)
✓ heavy snow or ice on panels that will not melt within the day
Clean your solar panels on an overcast day when the sun is not super hot. You want to avoid a sudden change in temperature from cold hose water. Solar panels are made from pretty sturdy glass, but it’s still best not to shock it.
How to clean solar panels
First things first: don’t use soap to clean your solar panels! Soap can leave a residue that will block the sunlight.
That residue can then actually collect more dirt because it becomes sticky. There are some commercial cleaning products available for cleaning solar panels, but the vast majority of the time plain water is just fine.
To clean your solar panels, you’ll need:
- Garden hose
- Sprayer nozzle for the hose
- Ladder, if your panels are on the roof
- Other safety equipment, if you need to access the roof
- A squeegee with a long pole or a soft sponge, if your panels are very dirty
- *Optional: a purchased cleaning solution or a diluted vinegar solution (always check your owner’s manual before using anything besides water!)
Basic cleaning practices
For most cleaning tasks, you simply need to spray the solar panels with the hose and let the water wash the dirt away. Easy peasy!
Very dirty panels need extra cleaning
If your panels are super dirty or have things like bird droppings stuck on, you may need to do some gentle scrubbing with a squeegee or soft sponge. Spray some water, scrub carefully, and then rinse the debris off.
Safety first, always.
If you have solar panels on the roof, you need to be extra careful when you are cleaning them.
You may be able to spray from the ground up to the roof, so try that first. If you need to access the roof, do so safely and never climb directly on the solar panels.
If you think you are unable to do the job safely, there are professional cleaners who can take care of it for you.
Solar panel maintenance
Cleaning is just one part of solar panel upkeep. While cleaning your solar panels, it’s a good time to perform other routine maintenance. Your owner’s manual will give you the specifics, but generally you need to make sure all the electrical components are in good working order. You also should check for any other issues like hail damage, cracks, etc.
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