PowerWall 2 does not like cold temperatures

PowerWall 2 does not like cold temperatures

My TEG hasn't been able to communicate with my PowerWalls for several days. In Northern Virginia we've had temperatures in the teens and single digits (Fahrenheit). I'd noticed that they were charging more slowly, which is to be expected, but then I noticed that they were neither charging nor discharging at all, and my reserve (I leave 15% for power outages in Self Powered mode) dwindled to zero. I then noticed that my Tesla app showed 0x PowerWalls.

Called Tesla support a week ago, they said they'd push a new update the next day & I should call back if it still wasn't working. They updated the TEG on Friday December 29th. The app now sees one of the PowerWalls. It charged a little bit on the 30th, but I haven't seen any charging or discharge since (in fact I've been sending a bit of solar back out to the grid at certain times of the day).

So I called Tesla support again this week, and they confirmed that it's almost certainly due to the extreme cold. I was told that engineering is working on an update that'll keep the batteries warmed/preconditioned in colder temperatures, and that the system should just start working again on its own once the temperatures warm up. The rep also speculated that pushing the update to the TEG might not have caused it to recognize the batteries due to cold weather that day. We're supposed to go above freezing next week, so hopefully they're right and the TEG will again recognize the PowerWalls on its own.

I'll keep the board posted. As the second rep said, it's Tesla's first deployed winter for PowerWall 2, so hopefully they're learning and will have a software solution soon. Outside of this incident I've had zero problems since last summer.

spmeister | 04. januar 2018

Oh, and my PowerWalls and TEG are mounted outside the house.

shank15217 | 07. januar 2018

How did you get powerwall installed in Virginia? They don't even call me back.

deweyvt03 | 07. januar 2018

That must be why my engineer placed the powerwall in the garage for my plans, even though it is the opposite side of the house than the meter. It is rated for outdoor, but they said it would be better to be protected anyway.

spmeister | 07. januar 2018

Got a bit warmer today, and now both of my PowerWalls are visible to the app. My reserve is slowly recharging. Unfortunately it didn’t start until after sunset, so I sent 9.8kWh of extra solar power to the grid instead of the batteries. But at least it seems to be working again.

shank15217, I preordered them on the Tesla website early last year, and already had solar (from a different company). I also have a Model 3 preordered. Not sure any of that made a difference other than ordering not long after orders went online, though.

DarkSpearTriant | 08. januar 2018

Well at least they were willing to help you

jamesellman | 15. februar 2019

PowerWalls don't just dislike cold weather - they don't even like mild weather.
I live in Marin County near Tesla HQ and have a new PowerWall. Our bankrupt felon utility PG&E often lets the grid go down in this area and while the PowerWall kicks right in when that happens, it usually won't take any charge from the solar PV system while the grid is out. This is because the battery can't accept a charge at under 50 degrees Fahrenheit. The battery is able to heat itself when it is connected to the grid, but Tesla is 'working on a driver update' to allow the system to do that in 'off-grid mode'. Today it is 51 degrees and sunny but the grid is down, the PowerWall only accepted solar PV for 30 min today, the battery is drained and now our house has gone dark. Thanks, Tesla!. I note there is nothing in the Telsa marketing materials that mention that PowerWalls really only are going to work for you if you live in Tuscon or similar. In fact, I have seen a photo on the website of a cabin in the north woods advertising this system as great for 'off grid solutions' That is BS. Buyer beware or you too will end up with a $12K paperweight like mine. I'm sure that when the class action lawsuit starts up for deceptive advertising, Elon will claim it is all due to mean, mean short sellers.

Tesla-David | 15. februar 2019

@jamesellman what you are reporting is demonstratively not my experience with our 2 powerwall in Edmonds,Washington. Our batteries work as advertised and we have had temps down to 16 degrees with no apparent problems with charging or discharging with solar. The PW2’s are an incredible product and I have been delighted with ours.

jamesellman | 16. februar 2019

Tesla-David: I have had no problems with the Powerwall when the grid is operational. The problem is when the grid is down and it is 50 degrees or less. Tesla claims that the Powerwall heats itself up to a working temp when the grid is up and running but it cannot do that when it is in 'off-grid' mode which takes place when there is a power outage. Have you had any outages concurrent with cold weather and had your battery continue to charge from the solar PV inverter? Thanks

Tesla-David | 16. februar 2019

@deweyvt103 Tesla-Energy told me that protecting the PW2 batteries by installing inside our garage would probably extend the usable life of battery. I am happy I chose that installment option. Other than problems with snow covered panels, our PW2 batteries have worked extremely well since installing on 6/22/18.

@jamesellman no we have fortunately not had any brownouts/blackouts during ours recent and ongoing winter storm.

jamesellman | 16. februar 2019

I hope you do not have any blackouts...ever...but at some point you may have one. That is when you will find out that the PowerWall won't allow the solar PV inverter to pass current if the temp is less than 51 degrees F. At that point you will have only the power left in the batteries, and once that is gone you will have two big paperweights mounted in your garage until the grid comes back up no matter how sunny it is outside. Consumers only find this out if they call the 800 number and ask about it and then Tesla will admit that system will not work off grid in 'excessive cold'.
If you can get your garage over 50 degrees, the system may work off grid...but once it drops under that temp, the system will shut down. Good for you for mounting your system in a garage, Note that Tesla does not mention anything in their marketing about how they will last longer if installed indoors. The problem here is that Tesla markets these things to be rugged enough to mount outside and able to power your house for a week off-grid when paired with solar PV on site. That is just BS if they only work when they are warmer than a relatively temperate 50 degrees:

Guess what - when do most Americans experience blackouts? In the Winter. When do we need the Powerwalls to process solar PV current to keep the lights running? The Winter.
There must be some technical reason that the system can warm itself when the grid is on but cannot do so when the grid is off even if there is lots of power in the battery. I hope Tesla can fix this soon. Until then, my system fails at exactly the time I need it and is unable to provide the service for which I purchased the thing in the first place.

ripatriot | 19. februar 2019

that's why i insisted they install my powerwalls in my basement where it's always 60 degrees year round.

Tesla-David | 19. februar 2019

@ripatriot, your installation choice is the best one IMHO. Unfortunately I don't have a basement, but the garage location does provide some protection for the PW2's.

@jamesellman, I share your concerns about how the PW2's perform when we have a brownout/blackout. We fortunately do not get many up here in Edmonds, WA with our utility provider. We have only had a few primarily from wind storms, and they were of short duration. I installed my PW2's primarily to enhance our self-sufficiency and prior to the onset of winter and lower solar were 100 percent self sufficient from June - October. They have been an incredible complement to our solar system, and have dramatically reduced our grid draws after our installation last June, and expect further reductions with a full year of battery use. I fully understand your concerns and hope that Tesla-Energy addresses your issues. I have read a number of cases from Australia, where the PW2's operated flawlessly during blackouts to keep the lights on during localized blackouts there.

Tesla-David | 19. februar 2019

Here is an example of PW2 performance in 42 hour power outage.

abasile | 25. februar 2019

@jamesellman, if the Powerwall won't charge from solar below 10C/50F during grid outages, that is a serious issue and I do hope to see Tesla fix this soon!

Our Powerwalls are installed outdoors under a shaded porch, as we have no garage or basement. Our outdoor air temperatures are below 10C for a large fraction of the year, including some summer mornings as we live up in the mountains (SoCal) near ski resorts.

edalcommerce | 28. februar 2019

I recommend to install them inside the house always, specially in chill countries like Norway France, Germany or Spain.
I have seen some models of powerwalls in this website [url="][/url] , so the spreading in Europe is starting to get success.

cmichael | 03. mars 2019

@Tesla-David A little off topic but how much noise do the Powerwalls emit into a garage environment? I am also curious if they were installed on an interior wall and if noise is noticible within the house.


dortor | 03. mars 2019

In my garage in Aptos, CA - the Powerwalls make mostly no noise what so ever - when they do make noise it’s no louder than a refrigerator and I doubt it could be heard inside the house even when they are making noise.

pmcterry | 15. kan 2019

@jamesellman Did you ever have any resolution to your issue? We had a system installed this winter and we are still working out the kinks. The last major kink seems to be exactly what you describe. When the outside temps fall below 50 degrees and we are off grid, the battery will not charge from the solar. Above 55 degrees, we were able to make it work exactly like it was supposed to. We are in rural Northern California in the redwoods and fog so we are below 50 a good part of the year. So far we have not been offered a solution other than "Tesla is working on it." I am very surprised that I can't find more information on this issue.

stupidnenu | 15. kan 2019

The rep also speculated that pushing the update to the TEG might not have caused it to recognize the batteries due to cold weather that day.

bfabry | 23. oktober 2019

Has anyone on this thread had any resolution to this problem? Maybe with a software update? We are in the process of buying a powerwall 2, and the sales person assured me that it would charge via solar, even when the grid power goes down and it is below 50F. We are in New England, and are trying to decide if we want it installed in our garage or our basement. I'm reluctant to put it in our basement because of the remote fire danger. It would be right next to our 300 gallon oil tank for our furnace. The garage does spend most of the winter below 50 degrees.

charlesj | 23. oktober 2019

@bfabry thanks for asking this question. While my batteries will be in a garage that is well insulated, so far had no such cold garage but could have in the future.
All these issues. I guess it wasn't really researched for cold weather and grid being down at the same time.

aphoffman | 29. oktober 2019

I live in Northern California and the grid has been out for 4 days now due to PG&E's Public Safety Power Shutoffs. It's been a tough week for our communities, schools, businesses, and homes. And it's been truly catastrophic for the communities directly affected by fires. But it is (in theory) a great time to have solar+storage on my home.

But I just hit the same issue that you all discovered on this thread. The battery has gotten cold the past two nights and apparently will not accept a charge when the unit is below 52 degrees and in off-grid mode (per the Tesla Support team member I talked to). So my family missed out on most of the morning solar generation yesterday and today and will exhaust the remainder of the battery before the day is out. Why can't the Powerwall use its own stored energy (or the energy produced by the solar) to 'warm up' and then become operational again? It sounds like that's exactly what it does when it's grid-connected, but why can't it do so when in off-grid mode?

Serious design flaw - Tesla, please fix this! The Support technician I talked to said she would put in a ticket (INQ20191029-191) which hopefully will get elevated if more of us call / raise this concern.

Passion2Fly | 29. oktober 2019

It’s confusing because preconditioning uses either the grid or solar... this should be an easy fix...

During Preconditioning, the Power Flow screen may show energy flowing to your Powerwall from solar or the grid. This is normal behavior, and the energy is only being used to heat, not to charge.

paramagic63 | 30. oktober 2019

We are having the same issue but our PW2 went through two winters without an issue! This is pure Bullshit! How are we supposed to get through a winter storm cycle. No one at Tesla informed us of putting the PW2 indoors and that there would be this issue!

Once again, a monumental fail. But the tech support girl, karen, was totally inept. I asked her why this info had not been pushed out to the consumers and she had no answer. And apparently she runs the entire PW tech support as she had no supervisor, but then her supervisor wasn't available.

Teslas sucks at this point.

markschaeffer | 30. oktober 2019

I am a Tesla Certified installer, and have a Tesla PW2 installed on my own home. Tesla never instructed me during there installer training that the PW2 needed to be installed indoors.
I too, along with many of my customers during the PGE shutdown, experienced our PW2's not accepting a solar charge till sometimes late in the day, basically keeping the solar system off all day. I discussed the situation with a Powerwall Tier 2 support rep today, and he confirmed that if the internal temperature of the PW2 is not 50 degrees the PW2 will not allow the solar system to come on.
I agree with all on this post, this is unacceptable. The Tier 2 rep confirmed with me that the internal heater in the PW2 will only come on if the temperature of the battery reaches 32 degrees to avoid freezing, and this function is only enabled when not in backup mode. The Tier 2 rep said this situation can be remedied by Tesla Engineering Team, as long as they hear our complaints. He recommended we all send an email to stating our complaint due to cold weather causing PW2 to not accept solar charge.
I will continue to push hard on Tesla in this regard so they can release an upgrade to fix this issue.

nvjx | 31. oktober 2019

Totally unacceptable! Glad I read this in the nick of time and cancelled my powerwall installation scheduled for tomorrow. I live in the SF Bay area and was buying it primarily for backup but if it can not accept charge when the grid is down in 50 degrees temperatures I have no use for it.

aschro | 01. november 2019

Thanks everyone for sharing this. I just ordered 2 Powerwalls to go along with a new solar system, and it gets quite cold in the Winter where we live (well, by California standards). We get down to mid-30's regularly, and our low for last year was 15 deg F. Thankfully my garage is insulated, but I bet it gets below 50. This is absolutely something they should be working on fixing!

forum11 | 02. november 2019

This seems like a massive oversight, but given the age of this thread I wonder why Tesla hasn't simply fixed the software bug in nearly two years. As someone noted above, the preconditioning mode should be able to draw from solar. I wonder if the current lack of preconditioning suppprt on solar is due to some other issue that Telsa decided they would 'get to later' and maybe now realize they can't just fix with a software update. I'm glad I held off on a PowerWall purchase becase this is core functionality that I would expect just work.

YERMELL517 | 02. november 2019

I have been following this thread since the spring and am about to contract with Tesla for 3 powerwalls in New England. The installation will be in a very small insulated shed at my solar array. When I asked my Tesla rep about this matter this was the Technical Project Manager’s response “PV will re-charge Powerwall under all operational conditions, even during a grid outage. During a grid outage, the Powerwall sets up a “grid” frequency to allow for the PV to continue to operate and provide power to the backup loads & re-charge the Powerwalls. However, there is one circumstance where we have issues re-charging the Powerwall w/ PV - when the PV output is larger than the combination of Powerwall Re-Charging and Home Load Demand. In this case, the Powerwall will shut down the PV inverter and power the loads by itself. This is where the PV to PW Ratio comes from – only a max of 7.6 kW PV to 1 Powerwall, to ensure the PV can re-charge the Powerwall / Provide power to the loads in the home.“ and “Powerwalls are limited to an Operating and Optimal Temperature. When the unit is outside the Optimal Temperature Range, it will use some of the internal battery capacity to heat up / cool down the internal components of the unit to allow it to operate (“Heat/Cold Mode”) decreasing the efficiency of charging/discharging. If the unit is outside the Operating Temperature Range it won’t function until it is back within this range.” I am surprised to be reading that this is still a problem.

nvjx | 02. november 2019

Well my salesperson insisted that this wasn't an issue in an email so I went ahead and let them install the Powerwall yesterday figuring I have the OK in writing. It is charging fine today but the temp is above 50 and the grid is not down. So we'll have to wait and see.

charlesj | 02. november 2019

Thanks @markschaeffer for your input. Yes, this is beyond belief that the product was placed on the market with such restrictions. After all, it is useless when grid is down and battery temps so low. Great restriction of market where this is not a problem.

Passion2Fly | 10. desember 2019

with SW version 1.41.2, I've experienced the same behavior. Early morning grid failure, PW takes over but the solar was still down (sunny day). The PW's SOC was 50%. Called Tesla and they said that the battery temperature was too low (45F)... I live in San Diego for god's sake... However, I did not experience a communication failure. The phone App was working just fine. Eventually, 3 hours later, the air temperature was 65F and the solar came on. Another issue is that the PW can only handle a 5kW load regardless of the solar output. So, if you have 5kW solar + 5 kW PW available, you cannot connect a 7kW load (as an example). You're still limited to 5kW, otherwise it will trip the battery...

gregbrew | 11. desember 2019

I just sent Tesla a firmly-worded e-mail asking them to change the firmware to engage the heating loop in the PWs when their temp gets below 55 degrees F.

I live in So. CA just off the Pacific, and it *routinely* gets below 50 degrees here in the Winter. My PWs are configured for "Backup Only" (wildfire power shutdowns and earthquakes notwithstanding), and the 50 degree limitation takes away my (very expensive) "insurance" for about 15% of the year! Outrageous and unacceptable. I can't imagine what those of you with outside installations in actual cold climates feel about this.

reed_lewis | 21. desember 2019

When I had my two Powerwalls installed just this week, the installers told me that having them outside in Massachusetts is a bad thing. They will not work well at all. Luckily I had space in my basement for them so they are in a space which is always around 60-70 degrees so they are in a perfect environment.

It is a large basement so they will always be happy.

charlesj | 21. desember 2019

Reed_lewis; One lucky person to have that option.
I don't think my garage ever went that low but could be.

Jones | 24. desember 2019

2 powerwalls connected to a (non-Tesla) 10 kW array. Temp for the last two days has dipped to high 30's overnight and stayed in the low 40's most of the day. No problems with charging or discharging the batteries. FW 1.43.3

Jones | 24. desember 2019

Oh - and the powerwalls are outside mounted to baseline wall and not attached to the heated structure - they have zero protection from rain or temperatures.

edwardpalmer1952 | 30. desember 2019

Why can't we just boxes Tesla powerwall in with 3 thermostat (1) to move the air around when the temperature is over 17c and a thermostat to take the air out if the temperature is over 19c and a thermostat with a fan heater to keep the temperature 14c .
I know this is not the way to fix the problem but this would work

Passion2Fly | 30. desember 2019

The issue is with cold temperatures and off the grid. I agree that when the grid is on, the PW uses the battery pre heater to maintain the proper temperature range. However, when the grid is off, it seems that the preheater is not used and the battery cannot charge...

heiko | 04. januar 2020

It doesn't like hot temperatures either. We had 46 C today here in the Western part of Sydney and our Tesla Powerwall 2 stopped working when the sun hit it in the afternoon. It came back when the temperature dropped to a 42 C at 7 pm and the sun rays did not hit it directly anymore.

gregbrew | 04. januar 2020

I predict a PW sun shade in your future...

Patrick | 05. januar 2020

FWIW - We fit three PW2s in a 5’ x 5’ space in an interior room, partially to avoid any potential issues with hot or cold outdoor temps. They don’t take up much space....

Jones | 05. januar 2020

Contributing data to the discussion.
Ran a quick test this morning - PW fully charged and did a grid disconnect (in the dark) with temperature right at freezing. No problems with cutover and batteries began to discharge immediately. My model 3 (sitting outside and connected) did a car battery warmup and pulled about 4 kW about an hour into the test (still without solar support). When sun hit the solar several hours later, charging commenced with no problems. Reconnected to grid as batteries approached 95% charge. Total 6 hours grid disconnected with and without solar with temperature range 32-45 F over span of test.
I concur with @heiko about higher temps - there is a brief late afternoon period where the PW are in direct sunlight and, when combined with high ambient temps of about 100 F, the powerwalls do a panic and are not available. They come back as soon as the sun drops. I plan on adding a sunshade...

edwardpalmer1952 | 05. januar 2020

I think I have found a way around this problem by putting a box around Tesla powerwall in the winter months
Easy to set up

edwardpalmer1952 | 06. januar 2020

Can someone give me some idea of what is the best running temperature for Tesla powerwall to work in .

(1)What is the temperature that the air conditioning switches on when it's to hot
(2) what is the temperature when the heater starts up

I am just guessing what temperature is because what I have seen Tesla powerwall in the winter looks like 12c to 19c depending on how hard the battery is working a d am keeping the temperature around 14c if this is to low then I can put this up by controlling the circulation fan what I would like to know what is the ideal running temperature

Patrick | 06. januar 2020

I would think anything in the mid-range of specified operating temps would be "ideal".

Jones | 06. januar 2020

Contributing more data:
(10 kW solar + two PW)
latitude 38 location
Current environment - clear, cloudless
Start of test - PW fully charged, beginning temp 48 F
30 minutes last sundown, disconnect from grid.
Powerwalls assumed full house load without problems
Ran 18 hours to a lowest charge point of 32%, then began recharging via solar
Temp overnight dropped to 29 F at minimum and 53 F at time of reconnect
Reconnected to grid after 18 hours with batteries at 50%.
No incidents or issues at any time.

edwardpalmer1952 | 06. januar 2020

Thanks you Jones for information and would like to say I must say I haven't had any problems with my system so far but will have to do the same test when the temperature is low enough
Oh one question jones how old is your Tesla powerwall and when do you have the system put in

Jones | 06. januar 2020

Solar was installed September 2007 (SunPower system). Powerwalls installed March 2019.

edwardpalmer1952 | 07. januar 2020

That rules out the possibility of an upgrade I am starting to think if it's possible that the thermostat is set too high in the systems Which are having a problem because if the thermostat is setup to -10 when its only 10 then the system would switch off but I could be wrong and can't be over looked