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

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SageBrush said:
golfcart said:
You were specifically talking about "long trips" (not commuting) in the part I responded to.
If so, then irrelevant to the Oak Ridge or AAA results.

You cannot have it both ways. Either we are talking about short trips and then the refueling time is trivial for EV owners with convenient L2 charging; or you are talking about long distance driving and then the SINGLE cold soak penalty is diluted.

Which brings us back to why the AAA study is FUD:
Efficiency of short trips does not extrapolate to long trips;
EVs are designed to be heated differently than an ICE.

It's actually not irrelevant I was just responding to what you said specifically. Anyone who is not a complete moron would realize that responses that include quotes are generally responding specifically to what is in the quote.

There are two scenarios. One is short trips (daily commuting and running errands) and one is long trips (road trips requiring multiple refuels as quickly as possible). There are advantages and disadvantages in each scenario all of which have been hashed out in this thread already. Nice try though.
 
Sagebrush, I know that you believe that you're surrounded by morons, and now we all know this too. Do NOT keep telling us.
Why not ?
I spent years telling people they were making themselves sick. Occasionally they took heed
 
golfcart said:
Anyone who is not a complete moron would realize that responses that include quotes are generally responding specifically to what is in the quote.
In your case you were quoting out of context. Thus my reply that your comment was irrelevant to the AAA or Oak Ridge results.
 
SageBrush said:
golfcart said:
Anyone who is not a complete moron would realize that responses that include quotes are generally responding specifically to what is in the quote.
In your case you were quoting out of context. Thus my reply that your comment was irrelevant to the AAA or Oak Ridge results.

Once again not true. The comment was in reference to the two reasons you posted in response to Titanium48 (see below). Any mention of the Oak Ridge study from me came after your response to Titanium48 was posted and was in a different context entirely. You are 0-2, want to keep swinging?

Original Exchange In Question said:
SageBrush said:
Do ICE owners then say "Ahh, I guess that means I cannot take my ICE out for a long trip ?"
Obviously no, for two reasons:
1. is that they refuel more often
2. The other is that during a long trip the warm-up penalty is diluted by the length of the trip.

It would probably be useful to add

3. They can put 300+ miles of range back in their vehicle in about 2 minutes using a vast network of refueling stations as opposed to a best case scenario of an hour to do so in an EV. This is admittedly, at least in part, an infrastructure issue that could be fixed in time... but it explains a lot of the reason why people are more sensitive to EV range losses than ICE range losses.

For what it is worth, I would see about a 10% loss in winter range when I had my WRX on my daily routine using the heat at 70deg. I see about a 30% loss in my Leaf doing the same. Of course I don't drive my Leaf like that unless the family is with me but it is illustrative none the less.

For those who are sticklers about following EPA procedures, the Oak Ridge National Laboratory actually did compare ICE vehicles and hybrids using EPA procedures. They found the following:

Cold weather and winter driving conditions can reduce your fuel economy significantly.

Fuel economy tests show that, in short-trip city driving, a conventional gasoline car's gas mileage is about 12% lower at 20°F than it would be at 77°F. It can drop as much as 22% for very short trips (3 to 4 miles).

The effect on hybrids is worse. Their fuel economy can drop about 31% to 34% under these conditions.

Unfortunately they don't link to the actual study and I couldn't find it with a quick search. But they do offer a lot of helpful info on maximizing your winter efficiency in any type of vehicle.

https://fueleconomy.gov/feg/coldweather.shtml
 
I used to drive a '95 Honda Civic. Had it for 17 years and lived in and drove it in several climates over those years. For my use, it was more sensitive to the cold during short trips than we have experienced in our Leaf.

On one end of the spectrum, the Civic would get up to 43 mpg (without AC) on 40 mile long open freeway summer commutes I had for a few years, ~30mpg in the winter. At a different point, the car was used to commute ~4 miles in St. Louis, MO. It sat in an open garage in the basement floor of my apartment building. In the summer it would get ~25 mpg due to the warm up penalty. However, during 10-20 ºF winter days I got only ~13-15 mpg.
 
As SageBrush noted, distance matters (because, like preheat, once the car is warm, it takes less energy to keep it warm). For a single trip, speed also matters. My Leaf uses 5kw to heat if I blast the Defrost. Using 5kw constant consumption for heat as just one example:

If you are driving at 85 mph for an hour, consuming 0.4 kw-hrs per mile for propulsion(*), then in one hour you’d spend 34 kw-hrs on driving and 5 on heating (13% of energy consumption spent on heat). The high driving speed uses lots of energy for travel, and the short time per-mile uses less energy per-mile for heat.

But if you’re driving a constant 45 mph for an hour, consuming 0.1818 kw-hrs per mile, then you’d use 8.18 kw-hrs on driving and 5 on heat ( 38% of energy going to heat). That’s almost triple the “percent” range loss versus driving 85mph.

A commuter with traffic jams or stop-and-go city traffic will have an even more lopsided loss (50%+?).

For a fixed distance (say, 20 miles), Freeway commuters vs Highway vs City vs Stop-&-Go/traffic jam drivers will have very different experiences with EV range reduction. The slower you drive, and the more times you stop, the bigger the percent loss in range. So is the true EV range loss 13% or 50%+? Trying to describe range loss using a single percent number is pretty meaningless.

It would be more helpful to describe range reduction as miles lost per quarter-hour of commute time (including all stops); and give separate values for "city" and "highway." Everybody knows how long it takes to get home (including shopping/kids), so they can visualize what their range reduction would be.

((*)energy consumption estimates taken from Tony Williams range chart)
 
specialgreen said:
For a fixed distance (say, 20 miles), Freeway commuters vs Highway vs City vs Stop-&-Go/traffic jam drivers will have very different experiences with EV range reduction. The slower you drive, and the more times you stop, the bigger the percent loss in range. So is the true EV range loss 13% or 50%+? Trying to describe range loss using a single percent number is pretty meaningless.
Fair POV, although I think the common day usage of 'range' is "can my car make it to my destination ?", not what will the efficiency be.
 
iPlug said:
I used to drive a '95 Honda Civic. Had it for 17 years and lived in and drove it in several climates over those years. For my use, it was more sensitive to the cold during short trips than we have experienced in our Leaf.

On one end of the spectrum, the Civic would get up to 43 mpg (without AC) on 40 mile long open freeway summer commutes I had for a few years, ~30mpg in the winter. At a different point, the car was used to commute ~4 miles in St. Louis, MO. It sat in an open garage in the basement floor of my apartment building. In the summer it would get ~25 mpg due to the warm up penalty. However, during 10-20 ºF winter days I got only ~13-15 mpg.
Exactly.

Now where is that AAA study exposing the horrible range of ICE cars ?
 
While ICE/piston technology is long matured and does have certain advantages in certain situations, EV tech is improving rapidly and will continue to do so for a long time.

Batteries are getting more affordable at more than a snail's pace, battery energy density is increasing, solid state tech is deep into advanced research stages and reliably around the corner, heat pumps continue to improve, charging infrastructure is growing, fast charging is getting faster, etc...

Still a BEV works well right now for a large percent of people, even in the middle of winter. It only gets better from here and becomes more convenient and more affordable for more people each year.

YMMV.
 
SageBrush said:
I think the common day usage of 'range' is "can my car make it to my destination ?", not what will the efficiency be.

Yes; I agree that "efficiency" will not be understood. I'm suggesting something simple like:

- City commute: 9 miles of range reduction per 15 minutes of commute time (*)
- Highway commute: 5 miles of range reduction per 15 minutes of commute time (**)

Find me a commuter who doesn't know how long it takes to drive home! A commuter who knows that it takes them 35 minutes to get home (counting a stop at day-care) in city traffic would guess that they will lose a bit more than 18 miles range in their winter commute (35 minutes = a bit more than 2x 15 minutes).

These numbers are probably off; I'm just going by the range calcs (which don't go below 45mph), and not counting things like snow tires, snow, etc. But with some real-world testing, you could get a pair of city/highway numbers that would be more helpful to the average driver than a straight "% miles reduction" number, and would account for both driving speed and stopping time.

((*)35 mph, 7 mi/kw-hr, 5kw heating sacrifices 35 miles range per hour driven, or 8.75 miles per 15 minutes)
((**) 60 mph, 4.3 mi/kw-hr, 5kw heating sacrifices 21.5 miles range per hour driven, or 5.375 miles per 15 minutes)
 
specialgreen said:
I'm suggesting something simple like:

- City commute: 9 miles of range reduction per 15 minutes of commute time (*)
- Highway commute: 5 miles of range reduction per 15 minutes of commute time (**)

Try it out on some of our challenged members.

Personally, I do something similar but in terms of power:
Pre-heat the car
~ 1 - 1.5 kW heating load between the seats and forced air-flow.
Then I figure 60 mph during trips so about 15 - 25 Wh/mile extra in the winter on dry roads
This matches up with my experience.
 
Any assertion that AAA is biased against EVs is unsupported by evidence. They did a test designed around routine daily driving, and as those of us who've follow this stuff closely know, BEVs suffer severe range loss in that scenario. As the majority of AAA members (and all car owners) don't have any experience with BEVs, and are unaware of the differences between their and ICE behavior (which we've had over a century to get used to), anything that gets the word out to a wider general audience (i.e., not limited to those who visit EV forums) should help eliminate much of the buyer's remorse that has been exhibited here and elsewhere over the past 7 years, when non-technically-inclined buyers find that their new BEV's range is subject to all sorts of caveats that often never even makes it into the fine print, and which may require them to make compromises or alter their own behavior in ways which an ICE doesn't.

There's a huge difference between "If I'm burning more gas while it's cold, I need to go to the gas station every five days instead of once a week", and "Do I have to chose between using the heat or getting home?" IIRR, the shortest period between BEV new car excitement, disillusion*1 and dumping it*2 reported here was about four weeks, when a member in Chicago got his LEAF on Dec. 21st, 2011, used it for a bit, experienced his first cold trip with his family in the car where he had to make just that kind of calculation above, and ditched his LEAF for a Volt which wouldn't require him to make that trade-off. Sure, if he'd known to ask about this before he'd bought the car we could have saved him several thousand dollars as well as considerable angst, but he didn't, nor should anyone need to find a specialized forum such as this one and know to ask to learn that info. Once everyone's used to BEV behavior people will know what to expect, but we're likely decades away from that sort of universal knowledge.

The only way for BEVs to become mainstream is to eliminate those concerns and compromises as much as possible by increasing the car's battery capacity (at an affordable price) so that they're no longer a factor, along with boosting the charging infrastructure and speed. Calling mainstream consumers idiots or morons for expecting that a car shouldn't control their lives isn't an effective alternative to get them to switch. I had thought that we were past this sort of elitist attitude here, but clearly some still hold it.


*1https://www.mynissanleaf.com/viewtopic.php?f=48&t=357&hilit=chicagoland&start=560#p163317

*2 https://www.mynissanleaf.com/viewtopic.php?f=48&t=357&p=168416#p168416
 
The EPA says: "Fuel economy tests show that, in short-trip city driving, a conventional gasoline car's gas mileage is about 12% lower at 20°F than it would be at 77°F. It can drop as much as 22% for very short trips (3 to 4 miles)..."
https://www.fueleconomy.gov/feg/coldweather.shtml

Anecdotal evidence on my part, but only 22% drop on very short trips (3 to 4 miles) with an ICE is far too optimistic.

My former ICE experience at these temps is about a 40% drop in mpg going 3-4 miles at cold soaked 20°F compared to 77°F.
 
I was staying on the sidelines, but decided to reply with some observations:

Cold weather, short trip efficiency of gasoline engine vehicles varies a lot. I have a couple of 4WD vehicles with cast iron straight six cylinder engines. They take some time to warm up and provide heat in cold weather, but have minimal loss of efficiency. They also stay warm during short stops so that heat is available when restarting. The newer one is OBDII compliant and uses a bit more gasoline when cold trying to warm up quicker, but not a lot. Later versions of the same SUV (and other similar sized SUVs) that I have driven for work waste a lot more fuel during cold starts, but warm up much quicker (and cool off fast when turned off). It appears that the newer vehicles burn extra fuel to warm up the engine and get into closed loop emissions control mode sooner. I was really surprised how much gasoline it took using one of the newer SUVs as a portable office in 0 degree F weather (efficiency loss was way more than 22%). I have never read media reports of how much fuel the newer vehicles waste in cold weather.

It appears that AAA did not operate the EVs the way an owner would. They should have started with the car preheated while plugged in so that the first trip started with a full charge and warm car and then complete their short trip cycles. An EV is ideal for short trip use in cold weather as long as it has enough battery capacity to handle the daily driving needs because there is no wear from cold starts and no need to wait for oil pressure to build up before driving (the car is ready to drive as soon as it completes it boot up sequence).
 
I dislike AAA as much as almost anyone sane, but I don't think they're too far off here. My first year, immediately after replacing original tires with new EP442 Plus I was getting about 4.6 mi/kWh in early Fall and by "winter" (scare-quotes because Seattle rarely has winter) I was struggling to get 3.0 round-trip on the worst rain days. Between colder/stiffer tires, wet road and most importantly the need to run heat and AC to get good defogging with wet occupants of the vehicle and 100% relative humidity outside, it was a big surprise.
 
iPlug said:
The EPA says: "Fuel economy tests show that, in short-trip city driving, a conventional gasoline car's gas mileage is about 12% lower at 20°F than it would be at 77°F. It can drop as much as 22% for very short trips (3 to 4 miles)..."
https://www.fueleconomy.gov/feg/coldweather.shtml

Anecdotal evidence on my part, but only 22% drop on very short trips (3 to 4 miles) with an ICE is far too optimistic.

My former ICE experience at these temps is about a 40% drop in mpg going 3-4 miles at cold soaked 20°F compared to 77°F.
That article has a list of things to do to mitigate the loss of energy economy ... and limiting forced hot air is not one of them, but limiting heat seating is.

I wonder if the same fools who wrote the AAA article wrote the EPA article.
 
It appears that AAA did not operate the EVs the way an owner would. They should have started with the car preheated while plugged in so that the first trip started with a full charge and warm car and then complete their short trip cycles. An EV is ideal for short trip use in cold weather as long as it has enough battery capacity to handle the daily driving needs because there is no wear from cold starts and no need to wait for oil pressure to build up before driving (the car is ready to drive as soon as it completes it boot up sequence).

The above (emphasis added) would be more true in 2011 than it is now. With many people acquiring an EV while NOT having researched or driven one for years, the typical EV driver is now largely a myth. Having been told that they have a 150+ range car, a newbie Leaf driver isn't going to just plug in and preheat as some sort of instinctual behavior. They will get in the car and drive it, recharging it when it is low on charge, or plugging it in every night so they aren't worried about charge. Preheating is a behavior developed to deal with EV range way below 100 miles. It isn't something that is already embedded in American driving culture.
 
Most of the new EVs sold today would do just fine in bitter cold with average commutes and letting the driver do whatever (s)he wants to do with heating settings.

For those with no second car ICE/PHEV and substantially longer than average commutes, it’s still mostly the Tesla brand to go to at the moment.

With the range of Teslas and now Niro EV, Kona EV, Leaf e+, and others coming on line, this is mattering less each year for EVs.
 
Most of the new EVs sold today would do just fine in bitter cold with average commutes and letting the driver do whatever (s)he wants to do with heating settings.

Except for the ones who acquired their EV with range needs that approach the EPA range rating of the car. They, never having been told by the sales "people" about Winter range drop, are essentially screwed.
 
LeftieBiker said:
Most of the new EVs sold today would do just fine in bitter cold with average commutes and letting the driver do whatever (s)he wants to do with heating settings.

Except for the ones who acquired their EV with range needs that approach the EPA range rating of the car. They, never having been told by the sales "people" about Winter range drop, are essentially screwed.
Right, that is why I pointed out "most" would not have winter commute issues.

NHTS's most recent data (2017) notes that the average (mean) commuting distance by private vehicle was 12.71 miles. Although they don't report it, we know the median commute distance is even lower as we know the mean average includes those skewing the distribution with unusually long commutes (these guys need a Tesla or Bolt at a minimum from the current BEV offerings).

So a Leaf EPA rated "151 miles" range by EPA, even if it lost 50% of its range during the winter would still have 3x the needed range for the mean average round trip commute with no work charging. Sure, we also have to account for degradation loss (would be smallest in places that have bitter cold) and emergency provisions among other things.

Agree, education at dealerships is important and lacking.


https://nhts.ornl.gov/assets/2017_nhts_summary_travel_trends.pdf
 
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