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Hi guys,

I live in Fairbanks, Alaska. The possibility of owning a Gen 2 Volt intrigues me. I've got some questions for those that have parked their cars outside in extremely cold temperatures. For the purposes of clarity, I define extreme cold as between -25f and -50f.

1. Will the battery be damaged by being left unplugged in extreme cold for up to a week? what about plugged into 120v? If left for three weeks at -40f temperatures and worse, plugged into 120v, is there a certainty that the car will intelligently manage it's electrical limits to avoid battery pack freezeup? Are there warranty limits involved for such cases?

2. Does the engine have a block heater, or is the engine block otherwise warmed while being plugged in? Is 240v required for this?

3. Have you driven successfully in temperatures of -40 without fogging up the windows due to the cabin heating system being unable to keep up?

4. At stationary idle, at what temperature does the cabin heating system reach equilibrium and can no longer thaw the cabin?

5. On starting the vehicle in extreme cold, when it's been plugged into a 240v source, does the generator load up the engine? Is there a way to ensure the battery is depleted enough to make mandatory a charging cycle, even when plugged in beforehand? At -45, most vehicles don't reach operating temperature at idle because the cabin heat takes too much energy away.

6. Does the remote start/precondition result in a warm-ish car in extreme cold events?

7. Does the G2 volt have a coolant-based heater core as well as the electrical heater, or JUST the electrical one?

I am not concerned about mileage during extreme cold events - only that making the jump to an EV doesn't represent a leap back for me to cars of the 80's that manage their heating and cooling systems poorly. If the vehicle makes me miserable during cold weather events, it's not an acceptable choice to me. I'll likely try to rent one before I buy, if the responses here are positive.
 

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As I understand it, extreme cold doesn't damage lithium ion batteries. If the electrolyte in the cells gets down to -17F (requiring an extended cold soak well below that - the pack is insulated and has a great deal of thermal mass) and freezes, then the car requires that the pack be thawed out before driving (there's an error message we've never seen actually occur aside from sensor failure "Battery too cold, plug in to warm" which GM created for this.) It sounds like your unplugged sitting case might reach that condition.

The engine does not have a block heater; the car could in theory use the 6 kW cabin coolant heater to heat the engine but we've never seen an indication the GM does this. Since the main purpose for a block heater is usually to make sure the engine can crank, it seems less relevant in a Volt, where a 55 kW electric motor grabs the engine and forces it to operational RPMs under 360V battery power. The engine will spin, period. In the extreme cold, I wonder if it might not be beneficial to warm it to reduce the thermal shocks, but GM may not be worried about that.

The engine is always under load when it is running, except for moments of idling when shifting into or out of Power Split mode (which only applies to Gen 1 Volts.) The normal warmup cycle is ~30 seconds at ~50% throttle; under most conditions the engine will be at full throttle at lower rpms.

I believe that the Gen 2 Volt system is identical to the 1st gen heater system - in which case there's only a conventional heater core in the cabin. In the engine bay, there's a 6 kW electric coolant heater and an electric coolant pump that heat this heater core normally, but it can also be linked by a valve to share the engine's coolant path and thus be heated by the engine instead (and is automatically once the engine coolant is warm.)
 

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I would suspect that if you could keep it plugged in to 120v at all times it is not being used, you will find it the same as any other vehicle in extreme cold. Unplugged though, as mentioned above, you likely will exceed the battery low temp limits and this may strand you. When the lithium battery is that cold, the only heat and propulsion will come from the engine and I think it will result in a reduced propulsion mode (others will have to chime in here).

I suspect in Alaska, you have 120v or 240v plugs everywhere as normal vehicles would require this for block heaters.

GM did test the Volt in extremes so Alaska is likely one of the places they tested. The other issue you have is a supporting dealer that can service the Volt should you have issues with it. Dealers need to have some special tools and have to make an investment in training etc to be able to service the beast.

There are certainly volts around that live in very cold regions such as Northern Manitoba but the lengthy cold soak would still be rare in most of those populated regions.

With respect to the engine, you certainly would want to make sure you have the correct oil for extreme cold and then again for your summer months. Likely, people in Alaska are used to seasonal oil changes for that purpose.
 

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There are other users in Alaska here.

The volt will run as good or better than any ICE vehicle, provided you keep it plugged in whenever parked. It will keep the batteries from freezing like a block heater would keep an engine from freezing.
The engine will be running for heat basically all the time, though (unless you mod the temp sensor to disable that because you only need to go a very short distance). So you won't get much EV driving and you won't save as much gas as you might think.
But the car would start more reliably than any ICE out there.

If you don't plug it in, see thread in my signature for more details of what happens in extreme cold.
 

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"1. Will the battery be damaged by being left unplugged in extreme cold for up to a week? No. What about plugged into 120v? No. If left for three weeks at -40f temperatures and worse, plugged into 120v, is there a certainty that the car will intelligently manage it's electrical limits to avoid battery pack freezeup? Yes. Are there warranty limits involved for such cases? Don't know.

2. Does the engine have a block heater, or is the engine block otherwise warmed while being plugged in? There is no traditional block heater. Is 240v required for this? No, the Volt will maintain the core battery temperature within an acceptable range (hot or cold) as long as the Volt is plugged in to Level I or Level II EVSE.

3. Have you driven successfully in temperatures of -40 without fogging up the windows due to the cabin heating system being unable to keep up? NA (There is a Youtube video you can checkout of a Volt owner starting and driving his Gen II Volt at between -15 and -25F https://www.youtube.com/watch?v=oo1Umb4K3vk)

4. At stationary idle, at what temperature does the cabin heating system reach equilibrium and can no longer thaw the cabin? Don't know. At milder winter temperatures the engine heat seems come on once the engine coolant reaches 140 F.

5. On starting the vehicle in extreme cold, when it's been plugged into a 240v source, does the generator load up the engine? I don't think so. Anytime the outside temperature is below 15 F and you start the Volt the gas engine will run, then cycle on and off as needed. The only way the gas engine will not automatically start and run at temperatures below 15 F is if the Volt is plugged in when you initiate a remote start cycle and have the Engine Heat Assist When Plugged in comfort setting is set to "No" (this is a safety feature to avoid carbon monoxide build up when remote starting while inside a garage.) Is there a way to ensure the battery is depleted enough to make mandatory a charging cycle, even when plugged in beforehand? No, I don't think so. At -45, most vehicles don't reach operating temperature at idle because the cabin heat takes too much energy away. In the Youtube video the Volt operates at between -15 and -25 F, at the end of the trip the Volt energy display shows that the Volt ran approximately 50% EV mode and 50% on the gas engine.

6. Does the remote start/precondition result in a warm-ish car in extreme cold events? Maybe not at -45 but normally if you set the climate controls to Auto, Maximum, "HI" temperature and recirculate setting and remote start the Volt (you can initiate up to 2 remote start cycles in a row before you must manually start the Volt) the car will be warm when you get in. The Volt will be warmer if the gas engine is allowed to run during the remote start cycle (assumes you are parked outside and plugged in.)

7. Does the G2 volt have a coolant-based heater core as well as the electrical heater, or JUST the electrical one? The Volt has a coolant-based heater core The Volt has 3 coolant loops, one radiator."
 

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I would suspect that if you could keep it plugged in to 120v at all times it is not being used, you will find it the same as any other vehicle in extreme cold. Unplugged though, as mentioned above, you likely will exceed the battery low temp limits and this may strand you. When the lithium battery is that cold, the only heat and propulsion will come from the engine and I think it will result in a reduced propulsion mode (others will have to chime in here).

I suspect in Alaska, you have 120v or 240v plugs everywhere as normal vehicles would require this for block heaters.

GM did test the Volt in extremes so Alaska is likely one of the places they tested. The other issue you have is a supporting dealer that can service the Volt should you have issues with it. Dealers need to have some special tools and have to make an investment in training etc to be able to service the beast.

There are certainly volts around that live in very cold regions such as Northern Manitoba but the lengthy cold soak would still be rare in most of those populated regions.

With respect to the engine, you certainly would want to make sure you have the correct oil for extreme cold and then again for your summer months. Likely, people in Alaska are used to seasonal oil changes for that purpose.
I would think 0-30 oil in Gen 2 Volts and likely 5-30 oil can handle -40. Mobil has a video showing that their 5-30 Mobil One flows at -40. I suspect 0-30 can go even lower.

I imagine aftermarket solutions for preheating the engine could be applied but think they're probably unnecessary.

The OP's question 4 is probably only something GM can answer with any accuracy. They probably did an environmental test that would give the answer.
 

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Just to clarify, as a few others have mentioned the extremes being unplugged but not the norms - if you leave the car plugged in to 120V or 240V, it will occasionally cycle it's HVAC as needed to maintain optimal battery temps (in your case mostly the heat). So if you run an extension cord to wherever you park it (if parked location is the issue for you) the system will maintain it's own internal temp while you are away from it.

The heating system should not have any issues keeping the windshield clear even in the extreme cold temps - the vehicle will cycle the engine on and off to provide supplemental heat below certain outdoor temps, so you may find in the extreme cold you aren't getting as much pure EV range as you are hoping for.

Some people thing the electric heat is enough, so have modified the outside temp sensor to fool the system into not running the engine, or running it at a lower temp. I'm not sure if that affects your warranty or not, personally I think given your location you should just expect the gas engine to be cycling on and off in the extreme cold. I'm not sure what the thresholds are for the 2016/2017s, I know for Gen 1 the low settings were 25F (early years) or 15F (later years) - below that temp outside and the engine would cycle.
 

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p.s. GM tests the car to work to at least -40.
The heater will work, but it will need the engine to maintain ability to clear the windshield from a cold start.

I alluded to it before in that you can disable the engine for heat for very short trips - but at -40 that would be a losing proposition except for short trips. You would remote start while plugged into 240V to pre-heat the cabin, because from dead cold start the electric heat is not as powerful as ICE. When preheated, it should be able to keep up.
 

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You may also want to view this thread and related videos. There's a Gen 1 Volt in Fairbanks and it seems to easily start up at -50F.

Although I would recommend keeping it plugged into an L1 EVSE, just like this owner was doing.

While the electrolyte is kept from being frozen, it seems the LCD screen isn't. ;) Expected at those temps I suppose.

http://gm-volt.com/forum/showthread.php?273874-Mileage-at-47F
 

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Discussion Starter #13
Thanks for all your input so far. Thanks especially for those of you that collected information from truly cold first-person experience.

The volt was tested by GM here in Fairbanks, Alaska. In fact, many automakers test their new cars here and there are businesses based around this, and lots of blacked out cars driving together at certain times. Unfortunately, you can't control the weather and sometimes the arctic winter testing isn't as extreme as desired.

Especially helpful is NPVolt's video in North pole. That was a -47 to -55 cold snap we experienced. The differences between that and temperatures as warm as -35 are much larger than the scale indicates. What works consistently and smoothly at -35 can be a completely different story at -45. That 10 degrees is where things die.

His window got stuck, that's not actually a bad mark for the car, that's normal. Few cars parked outside at those temperatures are able to open and close their windows without risking that. It's an example of operating outside the design parameters of almost all vehicles. Automotive grade gear is tested and supposed to operate down to -40F/C. Any further is operating outside design, and predictably, things go haywire.

I'm glad that NPvolt has proven that plugging in keeps the system warm enough to start in extreme cold. I'd further be interested in how much power the system consumes keeping things warm enough to work. Some back-of-napkin calculations have indicated to me that unless really well insulated, a 120v circuit may not be enough. At such extreme temperatures, up to 2KW of electric heating may be continuously required to keep the systems warm, assuming it's been plugged in the whole night. It depends on what temperature the system tried to keep the battery at when plugged in, anyone know?

I'm also interesting in knowing if he's got a block and/or pan heaters installed.

I'm still concerned about cabin heat. As I sort of alluded to before, I'm interested in making sure the car can be comfortable. My escape can fully warm up the cabin at -40, it's close though. I am un-interested in car that can't warm up when its needed the most, mileage be damned.
 

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With the ERDTT mod, the ICE still kicks in around 0°F.
The mod can be adjusted for any climate, if desired. That's just one resistor value that still bottoms out at 0F.
Some have also gone the other way and not have it adjust as hard as they're in a milder climate.
 

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I get more cabin heat if I run the generator? I did not have this certainty in my mind from reading many posts on this forum. I thought that I was totally dependent on electric heat. This modifies my driving habits on winter commutes in below zero temperatures. Regardless, I find the heating system deficient for my nine-mile commute distance.
 

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I get more cabin heat if I run the generator? I did not have this certainty in my mind from reading many posts on this forum. I thought that I was totally dependent on electric heat. This modifies my driving habits on winter commutes in below zero temperatures. Regardless, I find the heating system deficient for my nine-mile commute distance.
You've been here for a year and a half, surely seen dozens of ERDTT arguments and never knew what it was FOR? You're even in a place that will BENEFIT from it. :D
 

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The volt was tested by GM here in Fairbanks, Alaska. In fact, many automakers test their new cars here and there are businesses based around this, and lots of blacked out cars driving together at certain times. Unfortunately, you can't control the weather and sometimes the arctic winter testing isn't as extreme as desired.
They also test cars in Kapuskasing ON, not too far from my home town!

http://gm-volt.com/2010/02/23/chevy-volt-cold-weather-testing-update/

Some back-of-napkin calculations have indicated to me that unless really well insulated, a 120v circuit may not be enough. At such extreme temperatures, up to 2KW of electric heating may be continuously required to keep the systems warm, assuming it's been plugged in the whole night. It depends on what temperature the system tried to keep the battery at when plugged in, anyone know?
Reportedly the battery pack is well insulated so I don't think it would need more than the 960W even 8A provides. But ya, that wouldn't be nearly enough for the cabin.
Wonder if the system intelligently controls the valves to gives priority to the battery circuit?
 
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