Midwest Snow w Solar Panels and Cold w Powerwall

[guanchon]

hey here asking questions and requesting experience accounting of real world use...
Anyone here in the midwest with Tesla Solar Panels and experiences with the deep freeze and the Powerwall?

I hear that snow pretty much wipes out a nice sunny day for the next two weeks of solar energy production as remaining snow on panels?
Also, how much electricity is produced on heavy overcast that is usually in the winter?

Deep freeze / cold experiences w Powerwall?
I hear of troubles warming up the batteries before sun came up, preconditioning?
Where do people put the batteries?

I plan on putting the batteries in the garage.

 

[jjrandorin]

Im not in the midwest, but am wondering, with your concerns, what is it about solar and or batteries that is having you consider purchasing them? It looks like you have been researching this at least here since september of last year. What have you found during that time that has you considering moving forward?

 

[Big Earl]

Unless you have a roof that’s very difficult to access, using a roof rake to remove snow from the panels should get you back to full production right away.

Regarding cold weather, while not required, your best option is to install your Powerwalls in a location that is reasonably protected from extreme weather and temperatures. A garage is a great location, especially if it’s insulated.

 

[FurryOne]

I hear that snow pretty much wipes out a nice sunny day for the next two weeks of solar energy production as remaining snow on panels?
Also, how much electricity is produced on heavy overcast that is usually in the winter?

Here in Upstate NY we get less snow than we used to, but still... Even with 2-3" of snow cover your output drops to maybe 100-500w. Deeper snow will drop it even more. I have a raised ranch, and I use an 18' ladder to get to the edge of my roof, then I use a 24' telescoping pole with a rubber scraper to pull the panels clean in steps, collapsing the pole as I pull the snow closer to me. Here's what I use:

SnowBuster + 24' Extension Pole

DAMAGE-FREE PREMIUM FOAM MATERIAL, SAFE FOR SOLAR PANELS, VEHICLES, & ROOFS – The SnowBuster acts as a Snow Roof Rake and a Snow Broom, and is made out of soft yet super sturdy foam to ensure absolutely zero scratchings or damage. Perfect for removing snow from solar panels, roofs, windows...

eversprout.com

 

[guanchon]

Im not in the midwest, but am wondering, with your concerns, what is it about solar and or batteries that is having you consider purchasing them? It looks like you have been researching this at least here since september of last year. What have you found during that time that has you considering moving forward?

here waiting for the lease of my downstairs tenants to end to have the architect come to measure and plan for renovation in earnest, probably early summer planning and construction start late this year or early next year... trying to see what I can afford, what the bank will lend, and what will the project cost. all these pie in the sky ideas, solar, batteries... trying to go with less gas [induction cooktop, oven, water heather, clothes dryer], and if the budget is not bursting at the seams, maybe radiant heating using electric or, even, **gasp** geothermal. So maybe two or three power walls, and solar panels.

 

[guanchon]

Here in Upstate NY we get less snow than we used to, but still... Even with 2-3" of snow cover your output drops to maybe 100-500w. Deeper snow will drop it even more. I have a raised ranch, and I use an 18' ladder to get to the edge of my roof, then I use a 24' telescoping pole with a rubber scraper to pull the panels clean in steps, collapsing the pole as I pull the snow closer to me. Here's what I use:

SnowBuster + 24' Extension Pole

DAMAGE-FREE PREMIUM FOAM MATERIAL, SAFE FOR SOLAR PANELS, VEHICLES, & ROOFS – The SnowBuster acts as a Snow Roof Rake and a Snow Broom, and is made out of soft yet super sturdy foam to ensure absolutely zero scratchings or damage. Perfect for removing snow from solar panels, roofs, windows...

eversprout.com

wow. do you also have batteries?
solar working out for you? meeting most electric requirements?

 

[Zabe]

The problem that you will likely have in winter with powerwall's is not that they need to use a few kW's to precondition them, it will be not having much solar generation to fill them. With your electric heating needs you will not produce enough solar to do both or for that matter to even fill the powerwalls everyday in the winter.

With all of the changes you are planning you would need to estimate your energy needs in converting to all electric. You can start by figuring out how many therms of gas you use each year. 1 therm is about 100,000 BTU's of energy. If your furnace is 80% efficient or 95% efficient will impact how many therms are wasted.

An air source heat pump has about 250% efficiency, Geothermal about 400%. So each kW will produce 8530 BTU's for air source or 13648 BTU's for geothermal. The air source efficiency would probably be a little lower in your area due to all the days below freezing.

If your home has typical usage of 130 million BTU's with an air source you would need 15,240 kW and with geothermal you would need 9,525 kW. If you have a large home, or an older home with less insulation you will need more kW's, but you will figure that out via your gas consumption. Add those kW to your current usage and you can figure out the correct size system.

Next you would need to know how your utility deals with net metering. If they let you bank energy 1:1 all summer you should be able to properly size a system to meet the bulk of your energy needs. I do not know if they have rules for system sizing based on past usage, if they do you might not be allowed to build a big enough system to meet your future electric heating needs.

 

[zƬesla]

Here in Upstate NY we get less snow than we used to, but still... Even with 2-3" of snow cover your output drops to maybe 100-500w. Deeper snow will drop it even more. I have a raised ranch, and I use an 18' ladder to get to the edge of my roof, then I use a 24' telescoping pole with a rubber scraper to pull the panels clean in steps, collapsing the pole as I pull the snow closer to me. Here's what I use:

SnowBuster + 24' Extension Pole

DAMAGE-FREE PREMIUM FOAM MATERIAL, SAFE FOR SOLAR PANELS, VEHICLES, & ROOFS – The SnowBuster acts as a Snow Roof Rake and a Snow Broom, and is made out of soft yet super sturdy foam to ensure absolutely zero scratchings or damage. Perfect for removing snow from solar panels, roofs, windows...

eversprout.com

How well does the foam hold up on these? Mine is hard plastic (used only on shingle roof) and has held up for 20 years.

 

[sk00]

hey here asking questions and requesting experience accounting of real world use...
Anyone here in the midwest with Tesla Solar Panels and experiences with the deep freeze and the Powerwall?

I hear that snow pretty much wipes out a nice sunny day for the next two weeks of solar energy production as remaining snow on panels?
Also, how much electricity is produced on heavy overcast that is usually in the winter?

Deep freeze / cold experiences w Powerwall?
I hear of troubles warming up the batteries before sun came up, preconditioning?
Where do people put the batteries?

I plan on putting the batteries in the garage.

I'm in NY where winter weather conditions are also pretty terrible.

I have the solar roof (not panels) and snow seems to just slide off automatically, which is a huge plus. If you need a new roof, might want to consider the solar roof so you won't have to deal with snow obstructing solar production.

I also have 2 Powerwalls installed outside the garage. Ideally I wanted to have them indoors but due to very restrictive building fire code here, it would have cost me quite a bit more to have them inside the garage -- I would have had to build a closet around the Powerwalls with all sorts of other condidions. We just live in a very over-regulated state. You should research the restrictions in your town/state.

Temperature does seem to impact charging of the batteries. The temp here is regularly in the single digits or teens, and the batteries don't seem to charge at all below freezing temps. Other members here confrimed that this is probably normal. I'm not sure if this is also the case with discharging. Installing indoors probably would've solved this issue. I'm willing live with this as it impacts max 1-2 months out of the year.

 

[BGbreeder]

Low temperatures affect both charging and discharging of lithium ion batteries; whether that causes an issue depends upon the size of the ESS and your power demands. Regardless, moving them to a location where they aren't exposed to low temperatures would help, and will reduce internal power draws (parasitic) to warm the batteries.

What would be ideal is an enclosure outdoors that used temperature controlled ventilation to recycle the waste heat of the batteries to keep them warm, insulated them from solar loads in the summer, and would keep up with ventilation needs during hot spells. I don't know of such a product besides a temperature controlled garage...

All the best,

BG

 

[ThomasD]

Is Ice buildup on the panels an issue, Something like an Ice and Snow storm and several days of no Sun. Are the panels able to heat themselves to melt the Ice without any Sun?

 

[FurryOne]

wow. do you also have batteries?
solar working out for you? meeting most electric requirements?

Yes, I have 2 powerwalls - a Powerwall+ and a Powerwall2. On a clear winter day my Powerwalls are charged up by 1:30 and I have the reserve set to 75%. The 8K panels face East & West (4K each side) and generate up to 2.8Kw due to going through a tree that the sun misses in the Summer. Right now, after 1:30 my panels are throttled back (pre PTO) and my house only uses 500-900 watts.

 

[FurryOne]

I'm in NY where winter weather conditions are also pretty terrible.

Meh. The Mohawk Valley is listed as one of the least sunny areas in the US. (rats!)

I have the solar roof (not panels) and snow seems to just slide off automatically, which is a huge plus. If you need a new roof, might want to consider the solar roof so you won't have to deal with snow obstructing solar production.

I ordered the roof, and was told no installers in my area. After my panel install was started I found out they were installing a roof 10 miles away.

I also have 2 Powerwalls installed outside the garage. Ideally I wanted to have them indoors but due to very restrictive building fire code here, it would have cost me quite a bit more to have them inside the garage -- I would have had to build a closet around the Powerwalls with all sorts of other condidions. We just live in a very over-regulated state. You should research the restrictions in your town/state.

No problem in Rome. Just required the fire rated wallboard. Since I drive in from the right there's about 2' of clearance.

 

[FurryOne]

Is Ice buildup on the panels an issue, Something like an Ice and Snow storm and several days of no Sun. Are the panels able to heat themselves to melt the Ice without any Sun?

It depends on the pitch of your roof. I've had the snow build-up and then slide off the panels. My house is a raised ranch, so the pitch isn't that much, but 2 story houses usually have a steeper pitch. Otherwise you'll have to clean them off. No, they don't heat themselves, but like anything that absorbs the sun's energy, once they start getting uncovered the sun does a good job of melting snow (within reason).

 

[sk00]

Meh. The Mohawk Valley is listed as one of the least sunny areas in the US. (rats!)

I ordered the roof, and was told no installers in my area. After my panel install was started I found out they were installing a roof 10 miles away.

No problem in Rome. Just required the fire rated wallboard. Since I drive in from the right there's about 2' of clearance.
View attachment 764078

I'm in the hudson valley, a bit south east from where you are. When we installed our system last summer, Tesla said I was their first solar roof project in the county. There is an authorized local solar roof installer (SunCommon) so they probably did some installs in the area but their pricing was 2x Tesla's

Your system with 2 powerwalls and the Tesla inverter is probably the exact same as mine. We also probably follow the same fire code. I had just renovated our detached garage before the Tesla install, and had put on regular 1/2 inch sheetrock on the walls and left the ceiling completely bare. Tesla told me I had to have 3/4 inch sheetrock and it had to cover the entire space and not expose any wood. It was either that or I had to build a closet/room around the powerwalls, which would eat up a huge chunk of the garage space. In the end, didn't think it was worth the extra cost so installed them outside. Like your setup, I had to have 3 ft of space between powerwalls -- I've seen them literally stacked on top of one another or at least side by side in other states. Unnecessary and unproven fire code regulations in my opinion.

 

[nyprepper]

i'm in Hudson Valley NY too..... western Orange County. Snow and ice on the panels is a problem for me. I have the same roof rake linked to above. If it is just snow on the panes it works OK. however, in rain/snow/ice events with big temperature drops, fairly frequently we'll get a layer of ice on the panels, snow frozen on top of the ice, and another layer of crusty ice on the snow. in these situations if it stays very cold there is nothing you can really do except wait. this happened to me with last weekend's storm. We got about 12" of snow and sleet followed by single digit temps and I got zero solar production for 4 days. I watched vampire drain take my powerwalls down to 88% and just kept praying we wouldn't have a grid outage. the attached pic was taken on Monday....the snow event ended Saturday morning. red circle shows where my panels are.

 

[83girl]

I'm in NY where winter weather conditions are also pretty terrible.

I have the solar roof (not panels) and snow seems to just slide off automatically, which is a huge plus. If you need a new roof, might want to consider the solar roof so you won't have to deal with snow obstructing solar production.

I also have 2 Powerwalls installed outside the garage. Ideally I wanted to have them indoors but due to very restrictive building fire code here, it would have cost me quite a bit more to have them inside the garage -- I would have had to build a closet around the Powerwalls with all sorts of other condidions. We just live in a very over-regulated state. You should research the restrictions in your town/state.

Temperature does seem to impact charging of the batteries. The temp here is regularly in the single digits or teens, and the batteries don't seem to charge at all below freezing temps. Other members here confrimed that this is probably normal. I'm not sure if this is also the case with discharging. Installing indoors probably would've solved this issue. I'm willing live with this as it impacts max 1-2 months out of the year.

I live in Massachusetts, and we have had a few big storms so far this year. The snow routinely avalanches off of the roof during and after the storm, and we basically have had no obstruction on the solar at all this winter (when the sun is out). My next-door neighbor has panels, and they aren't as lucky for sure. Our powerwalls are in our unheated uninsulated garage, and no issues there either. Very happy with the entire system performance this winter. Now, if we can just get some more sunny days!

 

[h2ofun]

I live in Massachusetts, and we have had a few big storms so far this year. The snow routinely avalanches off of the roof during and after the storm, and we basically have had no obstruction on the solar at all this winter (when the sun is out). My next-door neighbor has panels, and they aren't as lucky for sure. Our powerwalls are in our unheated uninsulated garage, and no issues there either. Very happy with the entire system performance this winter. Now, if we can just get some more sunny days!

In the west amazing sunny warm weather! Solar doing great! Just about 60kwh in a day, heading back to my 185kwh per day in the best days.
I cannot believe it is winter, loving it!!! 75 today in Northern Calif

 

[slcasner]

I cannot believe it is winter, loving it!!! 75 today in Northern Calif

Not loving the lack of rain.

 

[h2ofun]

Not loving the lack of rain.

I am loving it!!! Nice and dry and warm