[RE-wrenches] RE-wrenches High snow load on PV Modules

[jason pozner]

We definitely deal with snow issues here in Crested Butte Co. We prefer pole
mounts when possible, and our winter tilt (55 degrees) sheds snow
adequately.  If not during the storm cycle, it easily sheds with first sun
on the array.  Our continental snowpack is drier, and tends to stick less
than your way, so that would also be a consideration.

The only problem we have seen on roof mounts is where the snow didn't crush
the module, but the torque of the entire "glacier" of snow trapping the
array while it was creeping down the roof pulled module clamps, and
destroyed a couple of modules.   The roof (see attached) was 12/12, but it
was a seasonal (summer only) cabin at 11,000'.  Nobody was around all
winter. The solution is maintenance/snow removal.  If the clients aren't
around to need the power like these, just cutting the snow so the array
isn't the only anchor of the slab of snow on the roof is the fix, otherwise
roof shoveling all winter.  We use a more robust rail (DP and W has done us
right), and err with more feet supporting the racking.  This drives up costs
a bit, but we sleep better....

Jay Pozner
Nunatak Alternative Energy Solutions
Crested Butte, CO
(970)349-3432
---------- Forwarded message ----------
From: Nunatak Alternative Energy Solutions <nunatakenergy at gmail.com>
Date: Wed, Jul 29, 2009 at 8:37 AM
Subject: luig
To: zzyyzzx11 at gmail.com




-- 
Nunatak Alternative Energy Solutions
Jay Pozner and Lena Wilensky
(970)349-3432
www.nunatakenergy.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20090729/5c3e4493/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: meginnis winter.jpg
Type: image/jpeg
Size: 45943 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20090729/5c3e4493/attachment-0005.jpg>