Solar Panels and Shedding Snow

Re: Solar Panels and Shedding Snow

I swept them solar panels off for the last time today for this winter. Spent almost an hour getting the snow off them this morning, got one amp-hour and then it started snowing again. When I went out to the woodpile before dark there was a foot caked on them, and they're tilted up to 15 degrees from vertical.

I just let my other power source that works rain, shine, raging blizzard, day, or night do its job for the rest of the winter 8)

[video=youtube_share;zNtjZa_fzxk]http://youtu.be/zNtjZa_fzxk[/video]

--
Chris

Re: Solar Panels and Shedding Snow

I don't even like Paul Allen, or football. Don't understand the first thing about the game. There was supposed to be Classic Rock on that station and what do I get? Football. I would've had it on a different station but the knob is gone off the radio so I can't change it.

This morning there was 4-5 tons of snow about 5-6 feet deep on the shop roof behind the solar panels. It slid down and broke 4 panels. There's about a foot of clearance between the bottom of the solar panels and the roof, but not near enough room for that amount of snow in one big hard-drifted block to slide thru.

This makes 12 that I've had busted due to snow load over the years. I used to have panels on a ground mount and they got buried under a 6-7 foot drift. I tried to dig them out and found 5 panels busted that time. I had some panels on a 8" diameter pole once and the wind tore those off and busted three - tore the bolts right thru the aluminum frames. And now I got four more on a roof mount busted.

I've threatened for several years to just take them down and put them in storage for the winter. As of this morning that would've been by far the cheapest way to go.

Our generator is completely buried under a drift too. I worked for a half hour this morning with the skid steer loader to dig out one end of it so I can clear the snow away from the air intake screens on it.

Wind was straight out the north all yesterday and last night at 20-30 mph with the big Toilet Flush circulation that pulls moisture off that big lake up to the north of us. Wind from the north is the absolute worst for drifting. The wind comes over the shop roof, the panels block it and it dumps tons of snow on that roof behind the panels. Take the panels off there and we have no problem with snow buildup on the roof.
--
Chris

Re: Solar Panels and Shedding Snow

Yeah. I think our insurance will cover the panels. They did before. But the adjuster is going to complain about not taking measures to keep the snow off the roof. But it's like, what am I supposed to do? It's not like I'm going to be up on a steel roof when the wind is blowing 30 mph trying to shovel it off. I had fully intended to get the skid steer over there, raise the bucket up and climb up in it and try to get that snow to slide off there a bit at a time with a long broom. It slid down before I got there.

I talked to my friend NW of Thunder Bay this morning - he said you guys got like 2-4" up there.

I think Thunder Bay is known as the "sunniest spot in Ontario". But I know you guys can get Big Snow too when the center of a low is more north and the rotation sucks moisture off that lake and pulls it north. The air gets warmed when it goes over the water because Lake Superior is so deep it only freezes over about once every 20 years. That warmed air can suck lots of moisture off the lake. Then it moves inland, the air gets cooled to the dewpoint and moisture in it falls out of the air.

Supposed to get down to 10 below F here tonight. I have to get the generator dug out yet because if that thing starts the heat will melt the snow around it and encase it in ice and I won't get to it until spring.

Speaking of Lake Superior freezing over, the last time it froze was in 2007. My wife and I were going to try to make it from Bayfield to Thunder Bay on the snowmobiles. We ran into pressure ridges about 30 miles out that were probably 10-15 feet tall. We couldn't get around them - followed one of them for about 10-12 miles to the east and ran into open water. Went back to the west for 30 miles and couldn't find a way over it. Finally turned back because we didn't have enough fuel left to get to Thunder Bay even if we could find a way over the pressure ridge.

30 miles out on that lake in the winter is an experience you will never forget. Can't see land in any direction - just snow as far as the eye can see. I don't know if we're young enough (and stupid enough) to try it again the next time it freezes over.
--
Chris

Re: Solar Panels and Shedding Snow

Historically, Superior has frozen completely over about once every 20 years. When it does we get bitterly cold weather here - 50-60 below zero. I think the record was 62 below in 1979. That was before I got married and a bunch of us guys made a 40 mile run that night on the snowmobiles to a bar and grille where we ate pizza, drank beer and played pool until 2:00 AM. Our sleds were sitting outside and when we went out to go home the thermometer on the outside of the bar said 44 below. We couldn't even pull the ropes to start 'em.

The owner of the bar let us drag our sleds into his garage and we heated 'em up with a kerosene space heater to get 'em started. Then all we all took off across the lake at 3:30 in the morning with the throttles clamped at 70-80 mph. When we got home it was 50 below.

LOL! Man, those were the days!
--
Chris

Re: Solar Panels and Shedding Snow

Actually, I think I could just lay the panels down to their summer position, which is parallel with the roof and about a foot off the roof. I'm pretty sure they would be fine that way and not catch the wind and make snow pile up, and on the sunny days in winter I could sweep them off and still get some power from them.

The problem with putting some sort of air dam is that it's a good 12 feet from the top of the panels to the peak of the roof. The bottoms of the panels hang over the eave so the snow will slide off onto the ground. And they're big panels - 250 watt'ers - so they stick up into air about 5 feet or so.

If I would've gotten there right away this morning when I saw all that snow backed up behind them and gotten it off there, it would've been fine. But I saw the generator buried, couldn't get the truck out because it tried to climb a drift in front of the overhead door and the top of the cab hit the door, so it seemed like getting the skid steer going and moving the biggest drifts out of the way was more important (at the time). The temperature was close to freezing all thru the storm so it was not light fluffy snow - it was laden with moisture and VERY heavy. You pick up a shovel full of it and there's so much water in it it's blue.

It was just "one of those things". Our insurance will cover the panels - I called them. The agent said it's a small claim, and we have had no real claims for years, so he's not even going to have an adjuster come. He said just send him a copy of the bill and he'll "take care of it".
--
Chris

Re: Solar Panels and Shedding Snow

That's right. If it would've been fluffy snow it would just break up and slide thru under the panels. That wet stuff makes drifts as hard as concrete that stay in one piece. When I was moving it with the skid loader it can't be pushed. I'd just drive into a bank and lift it in big 1,000 lb chunks take it off to the side and dump it, then push it up into a pile. Those piles of wet snow will set up tonight - it's already down to 2 above zero F here - and you will not move those piles even with a full sized end loader by tomorrow morning.

It seems to me that snow slides off solar panels easier than it does on the steel roof. I've had to break up snow and get it off the roof behind those panels before and I have to really work at it to get it to slide. Snow on the panel glass slides right off just like silk. So if I'd lay them down I wouldn't get the buildup anyway other than snow that falls straight down. And I'll bet that would be easy to brush off with a snow roof rake.

I've thought about it in the past but they're always tilted for the fall power (which is actually one of the best times of the year here. And I never think about it again until winter when they become a royal pain.

What broke the ones I had on the ground mount the one time was the fact that snow got on the top of them and nothing underneath. The panels couldn't support the weight of the drift and it bent them and broke the glass. I didn't know it until I got them dug out. Those panels stayed working for awhile but they got water inside and burned out within about 3 months. The ones that got broke today are still working too - it just bulged the panels from the back and broke the glass. But I tested them at the combiner and they're still putting out normal voltage. None of the glass is missing on the front - it must be like glued to the solar cells or something. But it's all shattered.
--
Chris

Re: Solar Panels and Shedding Snow

Yeah, you can't walk on it. But the snow won't slide on it either. I always lift the skid steer bucket up, climb up on top of the cab of the loader, then swing myself up on the loader frame to climb into the bucket and work from that with a snow rake. I don't trust a ladder because if a bunch of snow came off that roof when you're standing on a ladder, you'd end up on the ground anyway. When the snow slides off by itself and hits the ground sometimes it sounds like a 12 gauge shotgun when it hits the ground. I know I wouldn't want to be hit by 3-4 tons of snow when it comes off that roof.
--
Chris