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I was wondering if anyone knows what the coldest recommended operating temperature is for the Bolt. In the owner's manual I found a note about a message from the car stating that the vehicle could not be operated due to the outside temperature being too low.
 

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Not for sure but I believe it was -5 a couple of days the first part of the year when I got mine. I pre-condition the car below 35. No problems.
 

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Not for sure but I believe it was -5 a couple of days the first part of the year when I got mine. I pre-condition the car below 35. No problems.
I think in the extreme cold you need to precondition the car. The one weakness I see is the fact that the car doesn't have a heat-pump but rather an electric heating element. A heat pump would be more efficient at heating the cabin in cold temps. The battery has thermal management so I would imagine if you precondition the car you should be fine but it may not be the best choice if you live someplace like Alaska for example. The exact temp I don't know for sure but for preconditioning you would just have to account for the battery power it takes to do so before you are able to drive the vehicle if your not plugged in when your preconditioning. My understanding is that driving might be disabled but you should still be able to precondition to the point where driving is enabled.
 

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I think in the extreme cold you need to precondition the car. The one weakness I see is the fact that the car doesn't have a heat-pump but rather an electric heating element. A heat pump would be more efficient at heating the cabin in cold temps.
Heat pumps have limitations, OP said extreme cold, the efficiency goes down as the temp drops and vice-versa. Also the problem is that for defogging (a safety issue) you need two things, AC for dehumidifying and heat for drying and warming. So you have to have heating elements and AC at a minimum. Beyond that you can have a heat pump, but it does add cost and complexity. It may seem like a must have feature but it's not that simple.

I've been observing how the automatic climate control works. It appears that it defaults recirculation whenever possible which makes sense. When trying to cool it will also preferentially use the fans to provide cooling instead of actually using the AC. My only issue with the automatic mode is that it turns on the fan unnecessarily (like I'm trying to warm and it seems to be trying to cool).

I think the list of what to use is something like this

Trying to cool

  1. Precondition while plugged in
  2. Preferentially use the fans on a lower setting (avoid opening the windows to keep the aero)
  3. Use the AC on a low setting, it only uses 500W or so as far as I can tell
  4. Use recirculation when it's cooler outside (happens in my climate)
Trying to heat

  1. Precondition while plugged in
  2. Preferentially keep the fans on low or off
  3. Use the seat warmers and steering wheel warmer
  4. Use recirculation
  5. I've seen the heaters use 1KW-6kW, you have control over this AFAIK by where you set the desired temperature too. And better you have a physical knob to control it
My go to is to precondition to cool it down/heat it up, use cabin recirculation, and when it's hot I just turn on the AC and don't worry much about it as that's pretty cheap.
 

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Modern heat pumps are pretty darn efficient. How much complexity does it add? A reversing valve to allow the system to operate heat mode? Below say 20f it's not very efficient but the benefits in my mind outweigh any slightly increase in complexity. Yes you would still need the elements but you would not be using them as the primary source of heat. Elements are the most inefficient way to heat.
 

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Defogging worked "ok" on ICE cars without AC as long as you didn't try to recirculate. I'm skeptical the water heater in the Bolt would be able to achieve the insane hot air temperatures of an ICE car defroster, though. I do think the absence of a heat pump is a glaring missed opportunity.

I'm assuming as long as the battery is above 30% that conditioning will keep that car fully operable in the coldest climates the Bolt will be used in. It's that corner case of a long duration parking event, low battery SoC, frigid weather, no charging available that could get you in trouble. I would avoid that scenario below 0 degrees C if at all possible just to be safe.
 

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Modern heat pumps are pretty darn efficient. How much complexity does it add? A reversing valve to allow the system to operate heat mode? Below say 20f it's not very efficient but the benefits in my mind outweigh any slightly increase in complexity. Yes you would still need the elements but you would not be using them as the primary source of heat. Elements are the most inefficient way to heat.
Complexity = $$. Does it add lots of complexity? Yes probably more than you think. Belief is GM is already losing money on each sold. To get their range they went with a monster battery and made thousands of decisions as to how to do one thing or another. Marketing sets the end price, would you have given up a few or five kWh of battery for a heat pump?

Their decision was to not have some of the niceties like heat pumps and instead put as much battery as they could afford. You can always use more battery, but a heat pump is something you only use some of the time. Furthermore it's easy to work around the problem a pump is there for; just precondition, use the recirculation, seat warmers and recirc the heated air.
 

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Modern heat pumps are pretty darn efficient. How much complexity does it add? A reversing valve to allow the system to operate heat mode? Below say 20f it's not very efficient but the benefits in my mind outweigh any slightly increase in complexity. Yes you would still need the elements but you would not be using them as the primary source of heat. Elements are the most inefficient way to heat.
Complexity = $$. Does it add lots of complexity? Yes probably more than you think. Belief is GM is already losing money on each sold. To get their range they went with a monster battery and made thousands of decisions as to how to do one thing or another. Marketing sets the end price, would you have given up a few or five kWh of battery for a heat pump?

Their decision was to not have some of the niceties like heat pumps and instead put as much battery as they could afford. You can always use more battery, but a heat pump is something you only use some of the time. Furthermore it's easy to work around the problem a pump is there for; just precondition, use the recirculation, seat warmers and recirc the heated air.
Yes I know about economics. I know what they did with the Bolt. Tell me something I don't know other than you don't think the heat pump is nescessary. I fine if we just agree to disagree.
 

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Black Bolt "I'm assuming as long as the battery is above 30% that conditioning will keep that car fully operable in the coldest climates the Bolt will be used in. It's that corner case of a long duration parking event, low battery SoC, frigid weather, no charging available that could get you in trouble. I would avoid that scenario below 0 degrees C if at all possible just to be safe."

Here in Montana we're looking at lows in the -25 range over the next several days with highs only in the single digit range. I have not had any problems so far this winter but this will be the coldest stretch we've had in a long time. I don't have the option to plug in at work...any thoughts out there? I do have the option of using my Subie for a couple days...not that ICE cars are all that happy in these temps either.
 

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Here in Montana we're looking at lows in the -25 range over the next several days with highs only in the single digit range. I have not had any problems so far this winter but this will be the coldest stretch we've had in a long time. I don't have the option to plug in at work...any thoughts out there? I do have the option of using my Subie for a couple days...not that ICE cars are all that happy in these temps either.
Are you able to plug in each night? If so, then the car will keep the battery warm overnight with no problem. Can you afford to lose perhaps 50 miles of range during the day, since that power will be redirected to keeping the battery warm while you're at work? If so, then you should be fine. It's all just a numbers game: how much power is lost during the day to keep an already warm battery from cooling down too much, and how many miles do you need to drive? Unless you're going over 100 miles in your daily drive, or leaving the car unplugged for multiple days in a row, I expect you should be fine.
 

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Here in Montana we're looking at lows in the -25 range over the next several days with highs only in the single digit range. I have not had any problems so far this winter but this will be the coldest stretch we've had in a long time. I don't have the option to plug in at work...any thoughts out there? I do have the option of using my Subie for a couple days...not that ICE cars are all that happy in these temps either.
Bolt owner's manual concerns me on P.231 "Do not allow the vehicle to remain in temperature extremes for long periods without being driven or plugged in. It is recommended that the vehicle be plugged in when temperatures are below 0 °C (32 °F) and above 32 °C (90 °F) to maximize high voltage battery life." (the underlining is mine).

My concern: do I want to second-guess what this manual reference means ? A: No. I leave my Bolt plugged in during extreme cold. And I pay the piper 6-7 kWh's worth of EVSE energy each 24 hours when Bolt is idled+plugged-in, for battery conditioning in very cold ambient.

However I'm biased based upon 1.) having an alternate ICE "beater" vehicle for winter driving in highway war zone conditions, 2.) having new car pride, don't like getting Bolt dirty, salted, stone-rashed, 3.) ICE car warms the footwells nicely when you'd otherwise freeze your ass off in Bolt due to a.) much less heated air volume available in Bolt, + b.) you're too range-efficiency paranoidal and don't tend to really crank up the heat because you see clearly you're now chewing average of 30 kWh/100 km (2-ish miles / kWh), 4.) no one knows how long at what temp it takes to get Bolt to no-go threshold.

Hi <10F and Low -25F. 'oly sh1t. I'd leave Bolt plugged in.

Environment Canada says today in Toronto +3C/ 35F. Tomorrow +8C/46F. Yippee. I'll hand wash Bolt.

EDIT: forgot. re: Biased. I've got the factory slicks on - - no snow tires.
 

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Thanks mboni. Wait, am I at the Continental Divide in Montana taking advice from someone in Atlanta? ; ) Sure, if it seems sound...
I can plug it in at night on the only Level 2 charger for 60 miles around so I'll be doing that as range is not an issue for daily use. If the forecast turns worse I can always just park it in the garage, plug it in and run the Subie.
 

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Winter driving update from Montana

We've had an extended batch of cold weather at the Continental Divide here in Butte. The past week has been the warmest in quite a while with temperatures into the upper 30s and low 40s with abundant sunshine. We had a week of quite cold weather (for the 21st century..) with lows below zero every night and highs never reaching the 20s, and sometimes not even reaching the teens. The lowest temperature on the screen was -21. The WinterBolt drove like a dream, as smooth as ever. I was typically seeing range in the 180-200 and was using only the heated seat and steering wheel. There were a couple days when I couldn't get by without cycling the defrost on and off, but they were rare. I was plugging in overnight to keep the battery happy. I was gone for several days in Minneapolis, ironically co-chairing a Climate Changes session at a conference, leaving the WinterBolt unplugged. When I came back it had not lost any range from the indicated 185 but when I plugged it in for pre-conditioning it did use some energy for battery management. Since then with the slightly warmer temps and sunshine it's been doing great...when I plugged it in to charge last night I was showing 207 miles traveled and a range of 51 miles! I'd post a couple relevant pictures if I could figure out how! Aurgh...
 
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