[RE-wrenches] High Snow Load on PV modules

[Greg Egan]

My solution to snow load issues is to install modules on racks so they 
can tilt to 90 degrees when it's snow season.  I guess it depends on 
where you are but in the areas of Alaska where we work we tell people to 
tilt your array to 90 in the fall and kick it back to lat-15 in the late 
spring.  They gain some from snow reflection and lose some because 
they're not always at the best angle but they make a lot more power than 
modules installed under the snow.

We like top of pole mounts that allow for an 85 or 90 degree setting for 
the snowy season.  We've done some installs of modules on the s side of 
buildings where we leave them basically plumb during snow season and 
kick them out like an awning the rest of the year.  Sometimes there's a 
nice 2' overhang on the roof that keeps the snow off the wall mounted 
array even if it's kicked out maybe to 75 degrees or so.  Roof installs 
are our least favorite for a number of reasons.

I know the architects among us love to not see those ugly modules but I 
generally try to convince my clients that their neighbors will think 
they're stupid if  they see their PV panels under the snow.

Believe it or not we get most of our annual sunshine in the spring.  
It's clear and cool.  June has more "possible" sun hours but is 
generally cloudier so the NREL 30 yr averages show spring to be the most 
productive for us.  Don't want to miss out on that power if we can help it!

Best,

Greg


Greg Egan

Remote Power Inc.
981 Gold Mine Trail
Fairbanks, AK 99712
P. 907.457.4299

U.S.Distributor for Outback Power Systems and other premium power equipment.

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