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Sounds like the driver was on track to 200 miles EV range in bitter winter weather. That sounds very encouraging for winter range.
 

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Considering it was between 10 and 20 F and he was doing highway driving, 2.8 miles/kWh seems okay.

I still don't like the idea of perpetuating the myth that EVs are somehow so much more affected by cold than ICEVs. It's nearly the same percentage of range loss, so it only really matters if you are exceeding the vehicle's single-tank/battery range and need to refuel in a hurry.
 

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Considering it was between 10 and 20 F and he was doing highway driving, 2.8 miles/kWh seems okay.

I still don't like the idea of perpetuating the myth that EVs are somehow so much more affected by cold than ICEVs. It's nearly the same percentage of range loss, so it only really matters if you are exceeding the vehicle's single-tank/battery range and need to refuel in a hurry.
True, but that's a skyrocket of an "only if" that's a MUCH bigger deal for an EV, because it requires planning beforehand and enough time to watch an entire episode of Jessica Jones on Netflix, whilst for the conventionally-fueled, it's five minutes at gas station that you're hard-pressed to be NOT passing in the next ten minutes during most drives... Eventually, that won't be the case anymore, but it is now.
 

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Considering it was between 10 and 20 F and he was doing highway driving, 2.8 miles/kWh seems okay.

I still don't like the idea of perpetuating the myth that EVs are somehow so much more affected by cold than ICEVs. It's nearly the same percentage of range loss, so it only really matters if you are exceeding the vehicle's single-tank/battery range and need to refuel in a hurry.
It isn't a myth though. ICE improves in efficiency as the weather cools, due to increasing volumetric efficiency and improved Carnot cycle envelope (a colder 'cool' sink). This offsets the increased losses from higher air densities and wet roads.

Plus (of course) you get lots of 'free energy' (otherwise 'waste energy; in summer) to heat the cabin up with.

Meanwhile, as ICE improves in efficiency, everything in an EV gets worse, battery capacity, motor efficiency, etc.

I've never noticed any change in fuel economy from my ICE vehicles in winter, but it'll happily halve in winter in an EV with heating and will reduce by 25% or so without any heating (if I am an idiot for wanting to stay cold).
 

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I... everything in an EV gets worse, battery capacity, motor efficiency, etc...
Why would 'motor efficiency' (and the related inverter efficiency) go down in cold weather?

I can see a slight loss due to the ATF in the transaxle being slightly thicker, EV or ICE.

But an electric motor not liking it cold????
And the battery pack is in an insulated container that is heated or cooled as required when plugged in or power up.

BTW, every ICE I've ever had dropped a lot in the winter. Look at anyone keeping track on Fuelly year round.
 

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With ERDTT disabled I got maybe 15-20 mile range, and that is starting plugged in at one side of trip with high temps around 5 F.

As an experiment last week I drove on gas and was getting 24 mpg. In similar circumstances in the summer I get 40 mpg or 42 miles per charge. So in winter with gas I get about 60% my summer range, but with electric only about 40%. To be fair, I am using heat and the gas engine gets it for nearly free.

Without heat I might see 50% range drop because of the cold. Remember, a cold battery has higher internal resistance that reduces how much power you can draw from it. When the gas engine gets warm its advantage will be even larger in the winter.

I have my ERDTT enabled again, and using it with a high temp of -5 and it basically acts as hold mode in town as it runs almost constantly, recharging the battery. Figuring the added charge and I am getting around 25 mpg despite the bitter cold. If the battery actually dropped to that temperature it would be near unusable and trigger deep cold ERDTT.

Bottom line is EVs due take a much larger hit in winter unless you keep the battery warm. The Bolt will likely take a large range hit if parked outside unplugged on a night like last night at -18F and some wind.
 

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True, but that's a skyrocket of an "only if" that's a MUCH bigger deal for an EV, because it requires planning beforehand and enough time to watch an entire episode of Jessica Jones on Netflix, whilst for the conventionally-fueled, it's five minutes at gas station that you're hard-pressed to be NOT passing in the next ten minutes during most drives... Eventually, that won't be the case anymore, but it is now.
I don't think it's that much of a "skyrocket" when you can refuel at home. It really only matters for prolonged driving and road trips, which people generally try to avoid during harsh winter conditions.

It isn't a myth though. ICE improves in efficiency as the weather cools, due to increasing volumetric efficiency and improved Carnot cycle envelope (a colder 'cool' sink). This offsets the increased losses from higher air densities and wet roads.
That volumetric efficiency is only really a thing forced induction engines. With modern mass air sensors, your actual air fuel ratio wouldn't change, which is where most efficiency improvements come from.

Plus (of course) you get lots of 'free energy' (otherwise 'waste energy; in summer) to heat the cabin up with.
I wouldn't say "lots." You get enough to heat the cabin. Anything after that is still wasted.

Meanwhile, as ICE improves in efficiency, everything in an EV gets worse, battery capacity, motor efficiency, etc.
Not everything in an ICEV improves. ICEVs have far more lubricating fluids, their own batteries, belts, pulleys, pumps etc. that are all negatively affected by cold.

I've never noticed any change in fuel economy from my ICE vehicles in winter, but it'll happily halve in winter in an EV with heating and will reduce by 25% or so without any heating (if I am an idiot for wanting to stay cold).
I'm surprised to hear you say that. Every person I know who tracks their mileage in ICEVs reports significant impacts to fuel economy. It's ICEVs where this rule of thumb comes from: 6% fuel efficiency drop for every 10 F the temperature drops below 70 F.

Also, the percentage of energy it takes to heat the cabin drops as the battery size increases. On a Leaf, sure you might see 25-30% of your battery capacity go toward heating. But a Bolt would only need to allocate 12-15% of its battery capacity for heating.
 

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Happy to see objective data here to prove that it is merely a 'myth' that EVs are affected more than ICE.

I call BS. Not my experience at all.

I have been running diesels for the last few years, maybe they are affected more than 'gas'. I've tracked the fuel consumption continually and there's really been no objective impact by cold weather.

But we have a MPV 'gasser' at the moment now, with the Ampera, and it delivers 25mpg in summer. If I started seeing 15mpg in winter I'd have a fit and send it off for scrap! But going from 50 miles in the Ampera to 30 miles seems par for the course.

Sorry. No way. EVs are definitely more heavily impacted by cold weather than ICE. Absolutely no question about it, and you're BS-ing yourselves if you think otherwise.
 

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....Bottom line is EVs due take a much larger hit in winter unless you keep the battery warm. The Bolt will likely take a large range hit if parked outside unplugged on a night like last night at -18F and some wind.
So be nice to your BEV and ^ don't do that! ^:mad:

But what about the times when you leave it at the airport in the winter? Can't be helped.
Will the Bolt have some sort of 'Drop Dead' temp like the Volt has?
 

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Happy to see objective data here to prove that it is merely a 'myth' that EVs are affected more than ICE.

I call BS. Not my experience at all.

I have been running diesels for the last few years, maybe they are affected more than 'gas'. I've tracked the fuel consumption continually and there's really been no objective impact by cold weather.

But we have a MPV 'gasser' at the moment now, with the Ampera, and it delivers 25mpg in summer. If I started seeing 15mpg in winter I'd have a fit and send it off for scrap! But going from 50 miles in the Ampera to 30 miles seems par for the course.

Sorry. No way. EVs are definitely more heavily impacted by cold weather than ICE. Absolutely no question about it, and you're BS-ing yourselves if you think otherwise.
ICEs efficiency sucks all the time. Arguing about how much its efficiency is affected by the cold seems misplaced. As for the EV drive train, efficiency remains high, it's heating the battery and the cabin that are the extra loads that give us shorter ranges.
 

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ICEs efficiency sucks all the time. Arguing about how much its efficiency is affected by the cold seems misplaced. As for the EV drive train, efficiency remains high, it's heating the battery and the cabin that are the extra loads that give us shorter ranges.
Right. Pour $1 of gas into an ICE, waste about 75% ($0.75) as heat. The efficiency of electric motors is almost the mirror opposite. Put $1 of electricity into an EV, waste only 25% ($0.25) or less. I'm not sure of the Volt motor efficiency, but electric motors in general are far more efficient converting power into miles driven.
 

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I was intrigued by this sentence... "Chevy engineered the Bolt’s seats for maximum comfort and minimum size. I was comfortable throughout my drive.", given the recent thread on the uncomfortability and thin padding of the seat. (Third paragraph above first damage photo).
 

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Right. Pour $1 of gas into an ICE, waste about 75% ($0.75) as heat. The efficiency of electric motors is almost the mirror opposite. Put $1 of electricity into an EV, waste only 25% ($0.25) or less. I'm not sure of the Volt motor efficiency, but electric motors in general are far more efficient converting power into miles driven.
Pour $1 of gas into an ICE - about 15kWh of chemical energy, get 5kWh of traction enery and 5kWh of heat.

Pour $1 of electricity into an EV - about 10kWh of electrical energy (where do you live? what's your unit price?), get 5kWh of traction energy and 5kWh of heat.
 

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Happy to see objective data here to prove that it is merely a 'myth' that EVs are affected more than ICE.

I call BS. Not my experience at all.
As someone already mentioned, you just have to check fuelly.com to see the reports during winter months. Follow any of the fuel economy or hypermiling forums, and they will echo the sentiment that winter is the worst time for fuel economy, regardless of platform.

I have been running diesels for the last few years, maybe they are affected more than 'gas'. I've tracked the fuel consumption continually and there's really been no objective impact by cold weather.
If you are driving a diesel, then it is more than likely forced induction (not necessarily, but likely). So you will likely see a small improvement in engine efficiency due to denser air. However, you will also see additional pumping and heating requirements because diesel starts to get really thick in cold weather.

But we have a MPV 'gasser' at the moment now, with the Ampera, and it delivers 25mpg in summer. If I started seeing 15mpg in winter I'd have a fit and send it off for scrap! But going from 50 miles in the Ampera to 30 miles seems par for the course.
Again, smaller battery so a larger percentage of its charge goes to heating the cabin. Assuming half of the decreased efficiency is from heating, that would mean you're losing about 2 kWh to running the heater. That's 20% of the Ampera's available energy, but would only be 3% of the Bolt's available energy.

Also, continuing that line of thought, it would equal a roughly 20% drop in fuel economy for your MPV in the same conditions. Would you send your MPV off to get scrapped if it only got 20 mpg in winter? I hope not, because that is more than likely what you'd experience in those winter conditions.

Sorry. No way. EVs are definitely more heavily impacted by cold weather than ICE. Absolutely no question about it, and you're BS-ing yourselves if you think otherwise.
Define "more heavily." The only advantage ICEVs have is scavenged heat. In a Bolt, that's an additional 3% loss, which I wouldn't consider "more heavily impacted." Especially because you also have the option of preconditioning.
 

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So just to follow up, I figured I'd give a quick check of fuelly (haven't been there in ages). I couldn't find a way to filter by winter fill ups, but I thought this was interesting:

2003 MPV

Look at the average MPG for users. Then look at the average MPG for the two owners in Canada. Maybe Canadian drivers take their MPVs to the track a lot?
 

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So just to follow up, I figured I'd give a quick check of fuelly (haven't been there in ages). I couldn't find a way to filter by winter fill ups, but I thought this was interesting:

2003 MPV

Look at the average MPG for users. Then look at the average MPG for the two owners in Canada. Maybe Canadian drivers take their MPVs to the track a lot?
One thing about Canada or other northern locations, sometimes please drive with different rims with snow tires or studded tires or tire chains so the info might not be accurate...

I believe the bottom line is though, very few people are ready to buy an EV, discover the reduced winter range and pass on buying it...
 

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One thing about Canada or other northern locations, sometimes please drive with different rims with snow tires or studded tires or tire chains so the info might not be accurate...
It is a very small sample size to be sure, but I don't think you'll find any evidence anywhere that contradicts our assertion that ICEVs also suffer range loss in winter.

I believe the bottom line is though, very few people are ready to buy an EV, discover the reduced winter range and pass on buying it...
Which is why it is all the more important that we address these misconceptions before they take root.
 

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No I am not talking about with or without heater alone.

Winter with no heater is 20% to 30% lower EV range.

Winter with heater is 40% to 50% lower EV range.

Winter with more heating than you actually need is 0% to 15% lower gas range.

The issue is not for 'us Volt' drivers, we crank up the ICE so can exploit the waste heat. If you are very very clever with preconditioning and engine heating, and drive on dry roads not covered in dampness (maybe that is one difference to you guys - our roads are basically always damp in winter) then you can get within 10% to 15% of summer EV miles.

The problem is for BEV drivers who find their range that was adequate in summer is no longer adequate in winter. This is about a BEV.

But have it your way, believe what you want. If you want to start a counter-myth that it is no worse than ICE, please yourself. BS with no objective scientific control is how religions get started. Maybe you're right, just like maybe one of the many religions is right.
 

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Objective data proves that ALL vehicles suffer range/fuel efficiency losses during winter. It's less noticeable in ICEVs because they don't do a very good job of tracking fuel economy under any conditions. The myth is that EVs are significantly less efficient than their ICEV counterparts during winter, and we just don't have any proof of that. Sure, certain models of EVs (say a Leaf with no TMS on the battery) might be affected more, but that is because of poor engineering, not the fact that it is an EV.

Just be honest and objective about the facts; that's all I ask:
  • All vehicles suffer from lower fuel economy in cold, inclement weather.
  • All vehicles suffer from lower fuel economy as speeds increase.
To say anything else is misrepresenting the data we actually have available.

And yes, this is about BEVs, which is where the rule of thumb I mentioned comes into play. Expect to lose ~6% of your range for every 10 F the temperature drops below 70 F. Other factors can affect your economy too, but that will give you a baseline estimate of what you can expect for those weather conditions (assuming your other driving habits stay the same).

For example, if I get 250 miles of range for a given route at 70 F, I'm going to expect to only get about 170 miles of range over that same route in 10 F weather. Just as if I were driving an ICE that gets 25 MPG at 70 F, I'd expect to get about 17 MPG over the same route at 10 F.
 
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