[RE-wrenches] Dealing with snow

[Dana]

>From 7 to 13K ft in Colorado;

 

Snow does not really slid till 50 deg. This may not apply to ET SHW
collators.

Snow loves to build up at the bottom  of a panel if it cannot slide and
dump. Case in point - I had  4x10 SHW FP collectors that were 16” off the
ground and I came by as no-one was living in the house and snow was 4-5’
ramped up the collector.

Ice can as does build up if it slide down behind the panels, SHW & PV.
Depending on the storm cycle and climate.

Ground and pole, tracker mounts are best in snow country. Access is
important.

I mount as close to the ridge line as possible to keep snow and ice from
sliding behind. Stay High!

 

Charge controllers need to have room for the following – 

High Voltage and amperage from Cold.  At -25°F those panels are cranking. At
10,000 Ft. El. add 10%

High amperage from high elevation. I figure 3%/1000’ elevation over 5000 FT
El. .

High amperage from snow reflection. At 5,000 Ft. EL and above I add15% room
for over amperage.

 

I have installations at 13KFT and I have seen and measured up to 45%
additional output over rated panel spec due to the 3 items above. 

 

Hope this helps.

 

Dana Orzel

 

Great Solar Works, Inc

www.solarwork.com

E - dana at solarwork.com

V - 970.626.5253

F - 970.626.4140

C - 970.209.4076

“I'd put my money on solar energy
 I hope we don't have to wait 'til oil and
coal run out before we tackle that.”

—Thomas Edison, in conversation with Henry Ford and Harvey Firestone, March
1931

 

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of August Goers
Sent: Friday, August 14, 2009 2:00 PM
To: RE-wrenches
Subject: [RE-wrenches] Dealing with snow

 

Hi Wrenches,

 

I'm working on a PV installation best practices training agenda and I'm
trying to gather some info on dealing with snow. I don't have experience
with snow because I've always worked in the California coastal area.

 

Here are some questions which I'm hoping some of you might be able to
answer:

 

Roof mount applications:

 

1. Do you typically mount arrays flush to the roof? If so, I'm assuming that
roof pitches are generally designed to handle the various snow load and
snow-shed scenarios depending on how much snow the area sees?

2. Does the height off the roof matter? In other words, is it better to
mount low to the roof or higher above the roof. Does snow wedge under the
array?

3. Are there products out there designed to help shed snow?

4. Any other tips or opinions? Any stories?

 

Are there any tips for dealing with pole and ground mounts other than
tilting the panels really steep?

 

Thanks in advance. I'm hoping to hear from experienced Wrenches and to put
together a general set of guidelines for dealing with snow and ice in cold
climates.

 

Best,

 

August

 

 

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