Looking for solarpanel mount, winter angle adjustable, ice daming proof

[Philipp]

Hello Forum,

I am an architect from Switzerland having the chance to building in Canada.
It will be an offgrid small cottage home with solar power.

The design is a flat roof with the panels mounted a bit off the roof because of snow.

I am working with a local installer who has warned me that daming will be a problem and
has shown me pictures of broken panels.

I was wondering if there are any mounts which are flexible to give in to daming?
Or how is this usually dealt with? I thought that if they are a foot of the ground, they might
be covered in snow, but daming would't be a serious problem.


The other thing is, that I would like to be able to adjust the angle for winter time.
Are there no mounts which have two positions and can be angled by hand?
Something really low tech, same principle as a classic wooden beach chair..

thanks everybody!

Philipp

[bcroe]

Your problems will be less if you can mount panels on the ground, preferably at least 1 meter high, though in
Canada that may not be enough to keep them clear. Leave 20 cm gaps all around the panels to greatly
ease the work of clearing the snow. Bruce Roe

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[J.P.M.]

OP: listen to Bruce. I don't always agree with his opinions but he got his chops on the subject the hard way. Hard to argue with experience.

[DanS26]

IMHO leaving spaces between panels on a ground mounted array is not advisable. Yes, it may make for easier removal of snow but at the higher risk of damaging the panels during the cleaning process. The gap will allow the snow broom or snow rake to fall between the spaces subjecting the panels to a higher likelihood and risk of stress fractures especially in cold weather. Using a wooden pole instead of a metal telescoping pole will help mitigate the risk but it is still there.

[bcroe]

IMHO leaving spaces between panels on a ground mounted array is not advisable. Yes, it may make for easier removal of snow but at the higher risk of damaging the panels during the cleaning process. The gap will allow the snow broom or snow rake to fall between the spaces subjecting the panels to a higher likelihood and risk of stress fractures especially in cold weather. Using a wooden pole instead of a metal telescoping pole will help mitigate the risk but it is still there.

That is a problem, but much more of a problem for me is when reaching the far top and the
broom falls over the edge. I have a new design in process, that will put some cushion
behind the broom for the handle to fall on, and a ramp to allow just pulling it back and
onto the panels again. Pictures after it goes together.

No panels damaged in 5 winters. Bruce Roe

[DanS26]

Thanks Bruce. Look forward to seeing your design. Maybe I can incorporate into my snow broom design......see below:

IMG_1506.JPG

[DanS26]

I have found if you attack the snow from an angle there is less likelihood of fall thru on top but it still happens regularly....especially at the end of the cycle on the second array when I am tired.

My process is done in three passes...first pass is to push snow up and over the back (at an angle) on the top row of panels......second pass is to bring the snow on the third and second row down to the first row.....final pass cleans the first row. Fast and efficient with the three Sno Pros bolted together per pic above.

I should post a video since it took me a few years to perfect the method.

[Mike90250]

How can you install a flat roof in snow country ?
Why not a shed roof at your desired angle, and simplify panel mounting ? Or the ground mount if you have space.

EZ adjust like a wooden beach chair, won't work well when the first windy day comes along and shakes the stopper bar loose.

[Philipp]

Thank you all for your answers.

Trees
The panels should be on the roof to lift them up higher, there are a lot of trees. Cutting them is very limited, the height of the building helps.
Ground therefore is not an option.

Appearance
There is a spot closer by the lake, but the place is very private and other residents have voiced concern over seeing the panels from the lake.
(i know it's silly, but that's what it is)
There are new panels which come in all colours,.. is there anything like it from a North American producer/installer?
If I could hide them more, then that would surely be an option.

9b859198778bc1627057e15a180b8adc.jpgIntersolar-2015-Kromatix-04-web.jpg


Ice Daming
This is a holiday home, so often noone will be there to clear the snow. This is also why I though a steeper angle might help with the snow
falling off by itself?
By snow daming I ment the build up of snow under the panel, eventually breaking it, by pushing it up.
So when you upgrade an existing house with sloped roof, the space to the roof is a few inches.. how do they deal with the daming there?

Adjustable angle
of course the beach chair was an analogy, I was thinking there would be a locking mechanism.

@mike
The flat roof poses no problems at all with snow. This is a widely spread missconception. It's not like a sloped roof will somehow get rid of the snow by itself.
It actually just adds the risk of snow sliding down and burring someone. (at which point one starts to install things to keep the snow on top, which
then is the same as a flat roof again)
This is why the Swiss town of Davos (World Economic Forum) has implemented flat roof only policy way back, as they have 6-10ft of snow regularly.



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[J.P.M.]

Phillip: As an architect, you have access to information and have training. You have resources far beyond most here. In spite of those advantages, you sound like a neophyte in the area of solar design. While we can all learn something new and none of us is as smart as all of us, architects don't usually come to what are mostly DIY sites looking for direction. Usually, the information flows the other way.

Use your advantages to become knowledgeable in solar design before you attempt a design. Just a guess on my part, but it sounds (reads) to me like you have a lot to learn.

I'll get you started: Don't assume things are the same on different continents. Flat roofs, snow loads and flat plate solar devices present special needs and considerations that are somewhat separate from the energy production aspects of solar energy.

[Philipp]

Hi JPM, yes sure I have access, but mostly Swiss stuff. Like you said, it's all different.
The experience with getting information from local businesses, e.g. a solar installer is, that they
are very fixed on their one or two products they always do. Nothing out of the ordinary.
In forums like these however, one encounters people who like to tinker and try things and
most of all, don't want to sell me anything.
That's what I need.

[J.P.M.]

Understood. And I'm sure not selling anything. If I was I'd be rich from what I've otherwise given away around here. Usually, you get what you pay for (or less).

Just seems a bit unprofessional - IMO only - to seek what's unvetted information from semi or mostly anonymous sources. If I was your client, I'd be wondering if my choice of contracting your services was a wise one.

[azdave]

Welcome Philipp! Don't worry. Not everyone here welcomes our new members with a firm reprimand.

My experience with clearing snowy panels ended 30 years ago when I moved to the desert in Phoenix AZ. My home used to have direct air solar heat on the roof and to clear the panels I forced the circulation fans to turn on for 30 minutes to melt it. Won't work for you I'm afraid.

[J.P.M.]

Welcome Philipp! Don't worry. Not everyone here welcomes our new members with a firm reprimand.

My experience with clearing snowy panels ended 30 years ago when I moved to the desert in Phoenix AZ. My home used to have direct air solar heat on the roof and to clear the panels I forced the circulation fans to turn on for 30 minutes to melt it. Won't work for you I'm afraid.

Not a reprimand, just opinion. The way I learned it, not everyone who tells me what may be an unpleasant reality is being rude or unfriendly. As usual, take what you want of my mental spoor. Scrap the rest.

BTW, why give advice on what sounds like a thermal application and then say you're afraid it won't work ? Just sayin'.

[bcroe]

My estimations are that vertically mounted panels will not cost too much production during
the snow months (here at 42 deg Lat), while greatly aiding clearing snow. Panel washing
is not done, nature takes care of that. The bottom line is you must have direct sun exposure
for several of the best hours (around solar noon) to succeed. Experience here is, raising
panels one floor will only help for a few minutes, at the poorest sun times of day.

Its not too soon to ask what energy capability is desired. Keeping a few lap top, cell phone,
and some battery hand tools going is one thing. Expanding to 100W or 1000W class
appliances is another, requiring a huge investment, but which may not even be possible
given the space on one roof. good luck, Bruce Roe