AAA confirms what Tesla, BMW, Nissan electric car owners suspected — cold weather saps EV range

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EatsShootsandLeafs

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https://www.cnbc.com/2019/02/06/aaa-confirms-what-tesla-bmw-nissan-ev-owners-suspected-of-cold-weather.html

The AAA study appears to be the first to have used standard, repeatable methodology to confirm the problem.

A new AAA study finds that when the thermometer dropped to 20 degrees Fahrenheit, range fell by an average of 41 percent on the five models it tested.

I'm glad we are seeing some more attention to this because it is a serious issue. I personally found that single-digit F with a cold-soak resulted in a 50% range reduction in my 2012 Leaf, leading me to replace it before the lease was up with an ICE (this was several years ago).
 
There was another article posted the day before on cnbc that talked about the same thing, but more anecdotally based on individual users: https://www.cnbc.com/2019/02/05/tesla-jaguar-and-nissan-evs-lose-power-in-freezing-temps-.html

I agree its an issue, but I believe it really is only affecting folks who live in the coldest areas of our country that get down to below 0 Fahrenheit.
I grew up in Ohio, and even those temperatures are pretty rare. Hopefully, battery tech can improve, and people's expectations can be made appropriately when weather this cold happens.

What both articles I think fail to mention is how LITTLE power is required to run seat / steering wheel heaters. The power is so small (less than a few hundred watts combined with all other electronics / displays running) that the range hit would be less than half to 1 percent of the total range. I've seen at least a couple sources report that using seat heaters will reduce your range, which couldn't be farther from the truth.
 
I saw that this morning on the morning news. By leaving it to the news media to regurgitate semi-accurate info, the car makers and the EPA have dropped the ball. At least the warning about range is now getting out in some form...
 
Energy/mile drops as the length of the trip increases. The AAA 'study' fails to clarify this relationship.
And it fails to mention pre-heating.
And it fails to mention use of seat instead of cabin heating.

Absolutely garbage of an article.
 
40% range reduction?
Maybe only among the worst electric vehicle owners.
Only possible explanations I can think of is the battery is cold so there is little to no regen, they crank up the heat to the max, turn on the rear defroster, leave it on and drive 10mph over the speed limit on the highway.

If I did that on my drive to and from work I wouldn't make it back home.

I think a 40% range reduction is possible, but it would mostly the drivers fault.
 
Is there a link to more data from their study? I find it interesting that the article just states the overall EV average range hit without any delineation of how each car fared. In theory, Tesla's response could be accurate as they could have been the best performer in this test with stellar results but since AAA only reported the average of the 4 models in one number, there is no way to know.

While there are apparent issues with the study as noted in the above posts, at least it is a step in the right direction. We need more and better designed studies to understand and disseminate this aspect so the new consumer is better informed about what they are getting into. Very few 'first' studies of an issue are comprehensive. But they often are still valuable as they can provide a useful though not complete picture.
 
And we definitely need groups like AAA and Consumer Reports to do these studies. Ones done by the automakers will only see the light of day if they make their product look good. IIRC, without independent researchers on these types of topics, the who VW diesel-gate would have never come to light.
 
I find it interesting that the article just states the overall EV average range hit without any delineation of how each car fared. In theory, Tesla's response could be accurate as they could have been the best performer in this test with stellar results but since AAA only reported the average of the 4 models in one number, there is no way to know.

Tesla can "win" this only by finessing the rules a bit, and making the winner the car with the most actual range in the coldest temps. This ignores efficiency in cabin heating and focuses on 'brute capacity' instead. IIRC, there was a test of Winter range done in Europe, and the Ionic was the winner in efficiency, and maybe in actual range...assuming a 90 or 100kwh Tesla wasn't in the test.
 
DarthPuppy said:
Is there a link to more data from their study?
yes.
Each car was reported. IIRC the i3 and the Bolt fared the worst.
But I'll say it again: the trip length is paramount. The study is FUD
 
LeftieBiker said:
I find it interesting that the article just states the overall EV average range hit without any delineation of how each car fared. In theory, Tesla's response could be accurate as they could have been the best performer in this test with stellar results but since AAA only reported the average of the 4 models in one number, there is no way to know.

Tesla can "win" this only by finessing the rules a bit, and making the winner the car with the most actual range in the coldest temps. This ignores efficiency in cabin heating and focuses on 'brute capacity' instead. IIRC, there was a test of Winter range done in Europe, and the Ionic was the winner in efficiency, and maybe in actual range...assuming a 90 or 100kwh Tesla wasn't in the test.
No.
Although the "study" was too idiotic to understand the effect of trip length on estimated range, presumably all the cars were tested over the same trip length.

I found the test method.
https://www.aaa.com/AAA/common/AAR/files/AAA-Electric-Vehicle-Range-Testing-Report.pdf
It is the height of idiocy
a custom drive sequence
was constructed with a combination of EPA dynamometer drive schedules as specified in Appendix B of
SAE J1634. The UDDS was performed first, immediately followed by the HWFET and a ten (10) minute
soak period.
After the soaking period, the UDDS and US06 Driving Schedule (or Supplemental FTP) were
performed in succession. Immediately following the US06, a mid-test CSC at 65 mph was driven. The
distance of the CSC was specific to each vehicle and was selected such that the end-of-test CSC was
about 20 percent of the distance driven throughout the entirety of the test procedure. After the midtest CSC, the UDDS-HWFET-soak-UDDS-US06 test sequence was repeated and an end-of-test CSC at 65
mph was driven until the vehicle was unable to maintain steady-state speed. The constructed drive
sequence was utilized for all test vehicles and ambient temperatures.

AAA did not test winter range, it tested short drive winter efficiency by drivers who reheat the cabin every trip.
 
Oilpan4 said:
40% range reduction?
Maybe only among the worst electric vehicle owners.
Only possible explanations I can think of is the battery is cold so there is little to no regen, they crank up the heat to the max, turn on the rear defroster, leave it on and drive 10mph over the speed limit on the highway.

If I did that on my drive to and from work I wouldn't make it back home.

I think a 40% range reduction is possible, but it would mostly the drivers fault.
My worst ever day on a 12-bar 2012 Nissan Leaf consisted of a 100% charge. Car was on my driveway, so cold-soaked and it was low single digits I believe. Since it was terribly cold I had the heat on max, of course, and that is not driver error. I got to work, and then at the end of the day after it had been sitting all day I drove home. Again, all defrosting on/heat cranked because it was cold--same way I would in any car.

Speeds were probably 20 average, with a mix of country but since the weather was nasty that day a reasonable (but not crazy amount) of edging along in traffic due to people going slowly. I was by no means sitting in gridlock traffic just cooking myself.

I managed to turtle it right at around 35-37 miles, because by the time I got home I realized I had almost nothing left, so drove around my block until it turtled.

That was my first, and last complete winter with that car.
 
SageBrush said:
AAA did not test winter range, it tested short drive winter efficiency by drivers who reheat the cabin every trip.

How far off do you think that is from a typical commuters behavior? The average American commute is about 25 minutes and I suspect most people hop in the car and blast the heat until the cabin warms up.
 
golfcart said:
SageBrush said:
AAA did not test winter range, it tested short drive winter efficiency by drivers who reheat the cabin every trip.

How far off do you think that is from a typical commuters behavior? The average American commute is about 25 minutes and I suspect most people hop in the car and blast the heat until the cabin warms up.
Those drives are not where range comes into play.

You will notice that the EPA range test does not repeatedly cold soak the test every 30 minutes or so .
 
SageBrush said:
Those drives are not where range comes into play.

You will notice that the EPA range test does not repeatedly cold soak the test every 30 minutes or so .

I think it is relevant for 2 reasons

  • If your battery is <30kWh and your commute is >25 miles then winter range could be a huge issue depending on driving/HVAC habits. Range does come into play for these people just scan the leaf forum for threads about that exact topic.
  • Even a longer range EV owner making that kind of cold weather commute will see their efficiency drop considerably. Imagine you have an advertised 250 mile range EV and a 50 mile daily commute... the average consumer using the heat as any ICE driver might would be shocked to find their battery nearly depleted by Wednesday night.

If EV's are going to become mainstream these kinds of tests need to be done and discussed IMO. Of course the media will F* up the reporting, because that's what they do with anything technical in nature, but consumers need to be aware of these kinds of issues rather than just reading the EPA numbers all the time or getting their info from pie in the sky EV blogs that act like charging is 100% efficient, we'll all use seat heaters only, and everyone drives 55 on the interstate for their "real world" scenarios.
 
Testing a modern EV as if it is a degraded 24 kWh LEAF makes this "study" FUD
Using cabin heating in an EV instead of seat heating makes the driver a fool.
The EPA highway test does not simulate 55 mph driving.

The cabin heater pulls up to 6 kW at full blast and settles down to ~ 1 kW at steady state temperature. If Merkins were not abject idiots that would be all that is required to know and the echo chamber of FUD and propaganda could be constrained to the White House.
 
SageBrush said:
Testing a modern EV as if it is a degraded 24 kWh LEAF makes this "study" FUD
Using cabin heating in an EV instead of seat heating makes the driver a fool.
The EPA highway test does not simulate 55 mph driving.

The cabin heater pulls up to 6 kW at full blast and settles down to ~ 1 kW at steady state temperature. If Merkins were not abject idiots that would be all that is required to know and the echo chamber of FUD and propaganda could be constrained to the White House.

So basically if someone buys an EV expecting 250 miles of EPA range, commutes around 40 miles daily using the heat like they would any other car, and is shocked to find that they only get ~200 miles of range in the winter they are fools...

And if someone buys a used Leaf, Soul, Focus, or i3 EV expecting 80 miles of range, commutes around 40 miles daily using the heat like they would any other car, and is shocked to find that they can barely make it home in the winter they are fools...

Got it. Glad we have that settled. I think that'll make a great marketing campaign. Perhaps Mr. T is available. :D

And for the record I never said or implied that the EPA highway tests uses 55mph driving... You must be responding to someone else.
 
It was +4F this morning.
I set the climate control to 65F, recirculation of course, lowest fan speed, after about 15 miles it eventually settled to between 1.5 and 3kw. My guess would be close to 2kw and no where near 65F inside the car as there was some frost inside the windows.

Definitely getting a 5kw Eberspacher diesel fueled hydronic heater and installing it this spring.

I'm very comfortable when setting the house thermostat to 58 to 62F during the winter. I freeze slightly in the leaf.
 
golfcart said:
SageBrush said:
Testing a modern EV as if it is a degraded 24 kWh LEAF makes this "study" FUD
Using cabin heating in an EV instead of seat heating makes the driver a fool.
The EPA highway test does not simulate 55 mph driving.

The cabin heater pulls up to 6 kW at full blast and settles down to ~ 1 kW at steady state temperature. If Merkins were not abject idiots that would be all that is required to know and the echo chamber of FUD and propaganda could be constrained to the White House.

So basically if someone buys an EV expecting 250 miles of EPA range, commutes around 40 miles daily using the heat like they would any other car, and is shocked to find that they only get ~200 miles of range in the winter they are fools...
No
Per the AAA "study" a 250 EPA range estimated car would go about 125 miles in the winter. That is wrong because even the fools that use cabin heating instead of heat seating would find the heater power drops once the cabin reaches its set point.

This is not complicated: Even the EPA realizes that a range test should be continuous driving and not multiple cold soaks.
 
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