Who wants to play in my sandbox?

[Mike90250]

here's some panels under an inch of snow, at about +25F, in full sun for a couple hours. The white snow just reflects all the warmth the sun could put into the panels. The arrays cleared about 4 hours later, when the air temps warmed up.


sunnySnowPanels.png

[bcroe]

Bruce, Hows 35 degrees fixed tilt on the roof work for snow
self clearing - sliding off in moderate cold weather once the sun hits it.

Were you able to find any adjustable tilt mounts for single panels that would work on a pergola
and side of the building. The tilt makes a difference that shouldn't be ignored.

My rather limited research found only slotted racking for consumers. It was alleged it could be
mounted to tilt, but no real support for this. There were some pole mounts, but these do not hold
enough panels, tending to be too tall to easily reach if needed. If your coldest season weather
is often around or above freezing, panels may self clean before long. Not here.

When the snow does slide, it is best if it only slides off one panel, not across several. I prefer
landscape mount with space at the bottom of each row, your wall mount should do that. A
problem with roof mount, is snow sliding off gets piled up at the lower edge of the panel.
Mounting the panels high enough above the roof to avoid this seems to be impractical and
making a big wind load. I do not have a plan for roof mounts in snow, except make as much
power as you can in summer. Bruce Roe

[hardwired]

Mr2,

Looking at your pics of your place it appears you have a large lot and plenty of space for a ground mount. You absolutely need to install a ground mount system facing ideal south. If you run PVWatts I bet you will see a performance jump 15% maybe more.

In the winter you have the option to brush the snow off. You won't get to it on the roof and your punching a bunch of holes in the house or shed roof. On a large lot and no neigbors to complain ground mount makes a lot of sense particularly if your saddled with east west roof planes.


id put a border around it with weed block and some decorative stone. That's what I did around the above ground pool. No issues with mowing.

[DrLumen]

It seems like you have enough info from all their bids and suggestions to sit down, figure what you want along with deciding on roof or ground or both . Research the panels and systems as much as possible and then write it all out and use your specifications for them to bid on. It is hard to compare al the systems when they are throwing all these different options in the mix. Like a car lot, they are wanting all the differences as that allows them more pockets to stuff. Think undercoating and rust proofing and window etching and ... for cars.

If you spec the system then they will have to be competitive on the equipment and labor and meet any code/licensing/permit requirements. Then it is a matter of checking references and insurance coverage and the like.

I can't say I'm experienced in solar installs but this will work for any type of construction or improvements. Just make sure they are bidding on the same apple. It will make it a lot easier for you to make a decision.

[foo1bar]

You absolutely need to install a ground mount system facing ideal south.

And I'm looking at his shed and thinking "That probably would work for east-west array... - could do a high panel-to-inverter ratio to reduce costs."
Problem with that is snow-shedding... That roof probably gets a snow buildup in winter, so winter production would zero when you've got snow on the panels.

...and no we won't qualify for the Tax incentive

Are you SURE?
A lot of people think "I got a refund last year, I wouldn't get any benefit from the federal tax credit if I installed solar" - but they are misinformed.

Do you have last year's tax form? Was it form 1040? If so, look at line 16, "total tax". That's the line to look at to see if there's some tax that you can use a credit against.
If you work a job where you get a W-2, you probably have a bunch of $ withheld, and all of *those* withholding payments can be refunded, even though the solar credit itself is not refundable.

Good luck.

[donkey07]

Just a thought but have you thought about side mount solar frames which can attach to your east/west roof and face the panels south? They look a little more untidy but will give you better efficiency.

[donkey07]

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