Clearing snow from panels

[zƬesla]

For the northerners around here with accessible panels, do you ever clear snow and if so what do you use?

We are going into our first winter with a pole-mounted array and debating whether to have something on hand to clear deep snowfall. The roof rake is hard plastic so I don't want to use it on panels. Looking at something like the Extra Soft Snow Pro head:
Remove Snow From Solar Panels With the Snow Pro Soft Roof Rake

 

[nyprepper]

I have that same roof rake...Snow Pro with a 24' extendable handle. The blade is hard foam and I am not worried about damaging my panels. It's decent with snow removal, but it does nothing for ice. We have had several storms over the last couple of years that started with ice....then followed by heavy snow. In those situations you're pretty much screwed and just have to wait for it to melt. Ice and snow on the panels is the weak link in extended winter grid outages. I have had 7-10 day periods with zero solar production because of heavy ice on the panels.

 

[charlesj]

I have that same roof rake...Snow Pro with a 24' extendable handle. The blade is hard foam and I am not worried about damaging my panels. It's decent with snow removal, but it does nothing for ice. We have had several storms over the last couple of years that started with ice....then followed by heavy snow. In those situations you're pretty much screwed and just have to wait for it to melt. Ice and snow on the panels is the weak link in extended winter grid outages. I have had 7-10 day periods with zero solar production because of heavy ice on the panels.

Do you think a mixture of water and antifreeze sprayed on the panels would work after snow removal?
Curious as I don't have that issue yet.

 

[BrettS]

Do you think a mixture of water and antifreeze sprayed on the panels would work after snow removal?
Curious as I don't have that issue yet.

Antifreeze is incredibly toxic and pretty bad for the environment. I definitely wouldn’t want to just be spraying that onto my panels, especially if you had kids or pets that might be playing around your house.

Theoretically you could use an ice melt product, but I’d be concerned about that potentially etching or damaging the glass.

 

[SoCal Dave]

What is this "snow" you speak of?

 

[charlesj]

What is this "snow" you speak of?

Not his panels in Florida. He just responded to my query to another poster above mine.

 

[charlesj]

Antifreeze is incredibly toxic and pretty bad for the environment. I definitely wouldn’t want to just be spraying that onto my panels, especially if you had kids or pets that might be playing around your house.

Theoretically you could use an ice melt product, but I’d be concerned about that potentially etching or damaging the glass.

Alcohol mixture perhaps?

 

[getakey]

I never thought of snow. I'm just dealing with ash

 

[charlesj]

I never thought of snow. I'm just dealing with ash

Not yet anyhow we may be headed for an ice age, LOL.

 

[JeremyWhaling]

Curious that no inverter manufacturer has thought to have a "panel warming mode" which could run a small amount of current forwards through the panels to warm them up a bit...

Solar cells are just diodes after all, they'll actually emit IR if you pass a current through them.

 

[charlesj]

Curious that no inverter manufacturer has thought to have a "panel warming mode" which could run a small amount of current forwards through the panels to warm them up a bit...

Solar cells are just diodes after all, they'll actually emit IR if you pass a current through them.

Yes, but then you need another layer of control, on temp, off temp. And, if it ices over when no production, how do you send this tickle power to it DC? Back feed the inverter from grid?

 

[JeremyWhaling]

Yes, but then you need another layer of control, on temp, off temp. And, if it ices over when no production, how do you send this tickle power to it DC? Back feed the inverter from grid?

I would probably do a timer. And yes, inverter pulls from grid. I don't think you would need much power, really. Just enough to get the panels above freezing.

 

[mswlogo]

I've been cleaning mine, knowing the risk vs reward is stupidly high. I might spend 2 hrs to gain $2.00 of electricity. But it drives me nutty when the sun is beaming and panels are covered. I keep trying to think of a scheme to automate cleaning them. Like plastic sun shade or something. Even when the sun is beaming in winter, it doesn't generate all that much. So it's silly to put too much into it. But I still do.

I had the stupid foam snow rake too. It is absolutely useless.

I modified a standard snow rake and mounted a brush along the scraper edge. The brush is made for the bottom of like an industrial door or something.

It works GREAT. The brush is the only thing that touches the glass. It rides right over the screws holding panels down. And when snow is thick the the normal snow rake hooks and pulls the bulk of the snow off.

But it's kind of hacked together. I used nylon screw to attached the brush. It's an early prototype

One thing I'd love to do is put metal flashing or something at the bottom of the panels on the roof out to the edge of the roof. Currently all asphalt shingles. The snow slides down the panels and then gets stuck their (naturally when melting or when manually cleaning). So the top row of panels are clean and the bottom are covered due to the traffic jam of snow piled up on the asphalt shingles.

I love comparing a few neighbors in what they do. One does nothing and I compare how mine is vs his 2 days later. Sometimes his is solid frozen and think yeah it was worth it. Other times, his is squeaky clean and I never should have bothered. Another neighbor cleans his due to peer pressure I think he thinks he has to clean them because I always have. His faces the opposite direction so it's hard to compare results.

 

[zƬesla]

I had the stupid foam snow rake too. It is absolutely useless.

Well, there goes that plan. Guess I'll just wait and see what winter brings. These are pole-mounted and crankable in the vertical axis, so I'm hoping shedding will be easy (and automatic at the steep winter angle they'll be set at). May just need to shovel underneath to clear bottom panels row.

 

[GaitherBill]

I've got a regular snow roof rake. I'm curious if I clear the snow below and to the sides of the panels, the snow will just slide off the panels easier?

Not that we get tons of snow here, but I like to be maniacally over prepared.

 

[solarAddict]

I'm in MA , having solar installed on very flat roof (8 deg pitch) and dreading snow as my roof is very high and not easily accessible.
I was pondering an idea to come up with some high tech solution like for snow removal, something roomba-like but nothing good came out of it so far .

 

[ItsNotAboutTheMoney]

I've got a regular snow roof rake. I'm curious if I clear the snow below and to the sides of the panels, the snow will just slide off the panels easier?

Not that we get tons of snow here, but I like to be maniacally over prepared.

You're wanting the snow to warm up enough that you get enough melt that it becomes slick against the panels and slides off.

Just thinning the snow or exposing any surface to be warmed up by sun should help accelerate the melt.

Similar thing happens with driveways: snow on driveways melts away a lot faster if you can just expose some surface so it can warm up. Always regret getting lazy with snow clearance.

 

[GaitherBill]

You're wanting the snow to warm up enough that you get enough melt that it becomes slick against the panels and slides off.

Just thinning the snow or exposing any surface to be warmed up by sun should help accelerate the melt.

Similar thing happens with driveways: snow on driveways melts away a lot faster if you can just expose some surface so it can warm up. Always regret getting lazy with snow clearance.

Having lived in Maine for over a decade I'm well familiar with driveway snow.

Never had solar panels up there though.

 

[ItsNotAboutTheMoney]

Having lived in Maine for over a decade I'm well familiar with driveway snow.

Never had solar panels up there though.

I don't have solar panels, but I do have an aluminum roof. I'm assuming that a similar principle applies.

 

[mswlogo]

I've got a regular snow roof rake. I'm curious if I clear the snow below and to the sides of the panels, the snow will just slide off the panels easier?

Not that we get tons of snow here, but I like to be maniacally over prepared.

Cleaning the bottom edge of the roof will help a lot. But you will get the urge to pull some off the panels too.

BTW one other thing I tried was putting heat tape on the bottom section of the roof below the panels as well. That failed miserably. That heat tape provides paths to channel water away and prevent ice dams. But it does not melt the snow away. It just bores a hole through it. Ugh. All it did was get in the way of using the snow rake on the that section.