Snow Tolerant PV Mounting

[Mike90250]

Well here is a sad story in 1 photo. I can't fix this, but who expected 5' of snow ( not my array )

snow crushed panels PV solar.jpg

[sdold]

Will do, sometime after snow season ends up there. At least you're not getting our flooding.

[Mike90250]

And they had snow in Ft Bragg a few days ago too! Redding was shut down for 10" a couple days ago Holler at me next time you head through, we get a cuppa or something

[sdold]

That's crazy weather, Mike. We went through there to Fort Bragg on the 5th, and were advised to carry chains! They said it "snowed" at 500 feet in Gualala.

[Mike90250]

How the heck can you do that, mirrors?

nope, just ice cold weather, clouds clear, and ice cold panels kick out the volts.

here's a screen shot, depending on the particular day and conditions, the output can vary wildly
(apparently my controller is nearly 6 years old, Tristar MPPT 60 ) 3kw PV array

3622watts.jpg

[bcroe]

yesterday in the brief patches of sun that came out, my 3kw array was putting out
over 3600 watts !! yummy, the batteries love that

How the heck can you do that, mirrors?

Roller coaster weather here since the last of Jan. Snow, ice, sun, clouds, but never very warm. The the
high winter angle panels have consistently needed far less attention (sometimes none) to be cleared.
The last cycle I tried leaving snow on a low summer angle string to see what would happen (or maybe
just got tired of pushing snow). Temps running between 0 F and freezing. A couple days later we still
had not had enough sun to get the snow off, so I finished it. Bruce Roe

[Mike90250]

Wanted to add some pics from my place this last week (currently northern california is getting hammered by storms, rain, snow, 160 mph winds in the sierra mountains)
and yesterday in the brief patches of sun that came out, my 3kw array was putting out over 3600 watts !! yummy, the batteries love that



20190205_081100.png


After some sun - the melt started and began to slide off. Days have been like this, sun, snow, sun, rain, dark, snow, ice....

20190210_111052.png

That's 10 F in the IR thermometer on the gravel at my back porch. A little snow, some clear night skies and it gets cold
and you can expect your PV panels in winter, to get cold like this too, way below ambient air temps (about 25F)

20190205_074959.png

[johnhon]

I have 20 panels on a ground rack attached to my barn (7/12 pitch), 12 on a low (6/12) pitch pool house roof and 6 on my house (7/12 pitch). I use an aluminum snow roof rake. I duct tape a 2" piece of rubber pipe insulation to the outside ends of the cutting edge. It gives me about a 3/8" space betwen the glass and aluminum cutting edge. Works great.

[bcroe]

Today we have half an inch of ice on things, and complete overcast, 29 deg F. Despite
that the array is doing 3 KW. Nothing to do but wait for the sun to melt it, which may take quite a
while. But the ice is a lot thinner and completely transparent on the near vertical panels, which
are melting faster than the white over ice summer angle panels. Bruce Roe

Days later confirmed, temps always below freezing. The near vertical mounted panels were soon
completely cleared by the sun. The summer angle panels took some days for the ice to finally
slide off in sheets. Bruce Roe

[bcroe]

Today we have half an inch of ice on things, and complete overcast, 29 deg F. Despite that
the array is doing 3 KW. Nothing to do but wait for the sun to melt it, which may take quite a
while. But the ice is a lot thinner and completely transparent on the near vertical panels, which
are melting faster than the white over ice summer angle panels. Bruce Roe

[SunEagle]

Mike ... Great pictures of your equipment and sheds. At least you are getting some sun in CA.

[bcroe]

Got some 3" of snow last night followed by a sunny morning

Another hour and the panels had warmed and shed their snow, and power naturally, in the cold, really cranked
3Kw = 3281 watts (limited) (54V, 60.7A)
2Kw = 2231 watts
Air temp was about 30F About 8:30am

Those conditions did the job for you, might for me as well. However we NEVER see a sky that blue,
and varying degrees of clouds are the norm. And temps here are usually much lower. I have left
snow a little while, waiting for decent sun. Often the snow waits too. Bruce Roe

[Mike90250]

Got some 3" of snow last night followed by a sunny morning, and got some harvest numbers, of what the arrays produced with fresh white reflective powder on them
I got a pic of the panels, in the sun
and went to check the battery chargers, both were nearly useless
3Kw array 11 watts
2kw array 10 watts (my morning array for toast and wife's blowdryer)
Another hour and the panels had warmed and shed their snow, and power naturally, in the cold, really cranked
3Kw = 3281 watts (limited) (54V, 60.7A)
2Kw = 2231 watts
Air temp was about 30F About 8:30am
Background left - right Shop. Battery shed. Generator shed with chainlink door.
3Kw array in background, 2Kw array foreground.

20190205_081356.png

[bcroe]

I would be more worried about the low temperatures they are predicting for your area. Try to stay warm my friend.

Thanks, we are expecting severe cold Wed, but staying inside most of the time will cover that
if the power stays on. I have survived worse before retirement, would go out at noon and
run the car, to be sure it was going to start. When the PoCo statement comes in a few days,
will have more (pretty favorable) comments on mini split heat pump performance thru all this.
Bruce Roe

[SunEagle]

Another snow of some 7 inches, nearly 3 feet in Jan. Once again the panels set up for winter in fact completely
cleared themselves with a little sun. I am now going out to clear yesterdays snow from the panels fixed at a
good summer angle. Bruce Roe

I would be more worried about the low temperatures they are predicting for your area. Try to stay warm my friend.