Wildfires, ash, and cleaning rooftop solar panels

[jboy210]

I wonder if it would make sense for some panel manufacturer to make a self-cleaning model with a wiper blade. There could be a rain sensor and when the panel gets sufficiently wet, give it a wipe. Maybe not as good as a soapy mopping, but a wet wiping every time it rains would surely be better than nothing for those of us with high roofs we're not going to climb around on.

Youtube has a ton of videos on automated cleaning solutions for solar panels.

 

[Merrill]

For those of you that have a hard time reaching your panels and need an easy way to clean them think about a DI system with an extendable brush. I have a DI tank that hooks up to your water hose and a 18 foot fiberglass extendable brush. You use no soap and just wash with the DI water that flows thru the brush. It does a pretty good job and no need to climb and minimal spotting.

 

[aesculus]

I am giving this one a try this weekend. Kind of pricey.

https://www.amazon.com/gp/product/B07Y5VBWJY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

BTW my Smart Flower has brushes and it sort of works but I am always worried that they are going to scratch the surface. So far after 3 years nothing noticeable. It did seem to help this year. I only lost a few percent rather than 10-20% before they cleaned themselves.

 

[Merrill]

That solar is very cool, what is the output. I use the Xero system and also have a solarium to clean so although expensive to start it pays for it self after 3 uses, do not have to hire a cleaner and do not have to climb on the solarium.

 

[aesculus]

The SmartFlower is rated at 2.5 kW. My best situation ever was a real 2.2 kW. But that is highly variable. While it does track the sun, it suffers from heat issues. At about 90F the efficiency starts falling off dramatically. I have kept great records and during the summer months you can see the degradation in output at the higher temperatures. It's not unusual for it to clip at 1.8 kW or even lower for example when hot.

I was kind of surprised by this. Because the panels are free standing and on very thin AL backing, I thought it would self cool. It was designed in Austria and therefore I don't think ambient heating was a variable that went into the equation.

 

[Janus]

I wonder if it would make sense for some panel manufacturer to make a self-cleaning model with a wiper blade. There could be a rain sensor and when the panel gets sufficiently wet, give it a wipe. Maybe not as good as a soapy mopping, but a wet wiping every time it rains would surely be better than nothing for those of us with high roofs we're not going to climb around on.

Except when the wiper get stuck half way, and your daily production gets cut in half...

 

[heytae]

This thread inspired me to climb up on 2nd story roof to clean ours once again. Past 2 cleanings weren't that beneficial for our system, beyond a few days, but I was hoping that removing the ash from the 2020 fires would get me a bigger gain this year. I wish the results were better. Anyone have any theories on why one's cleaning results wouldn't be as big as much as another's, percentage wise? I was guessing that they'd be in the same ballpark. Maybe due to the size (benefit not as noticeable?) or age? 9 years old system, 26 185w panels for a 4.2kw system. I noticed our panels weren't that dirty, certainly not as dirty as some of the pictures in this thread. Picture below is of them pre-cleaned and you can see the temporary benefit after the cleaning. They were scrubbed vigorously with plain water, then squeegeed using the foam-based scrubber in the picture. The panels looked pretty clean and clear afterwards.

How does one get similar results like you guys? (assuming your cleaning benefits lasted longer than a week) Thanks in advance.

Post-cleaning. They looked cleaner than this camera angle shows. This picture actually looks washed out, pun not intentional. =)