I bought a 2020 Chevy Bolt about two weeks back. It’s an electric vehicle with a roughly 250-mile range. I did my research. Waited for prices to drop. Got a pretty good deal on a low-mileage car. I think. Post #1924 summarizes that.
And wouldn’t you know it, the very next week the news was full of horror stories about what a bad idea EVs are, owing to poor performance in the cold. Long lines at public chargers, people being stranded, people getting towed. The whole nine yards. This, accompanied by the usual sneering comments from John Q Public.
OMG, did I just make a huge mistake?
Nah.
Funny thing is, despite the cold here (got down below 10F several nights), I wouldn’t have known there was this huge issue, if I hadn’t read about it.
I figured I’d take one post to work through the nuances on this.
The nuances of the issue, in three easy steps
It’s not as if the facts of cold weather and electric vehicles are hard to grasp. It’s that they are so obvious that nobody in the press cares to cover them.
To understand the vast, almost incomprehensible amount of courage it takes even to consider driving an EV in cold weather, you must first break down what happened in this last cold snap into three pieces:
- Charge-at-home drivers, who largely had no problems.
- Public-charger users, who faced a weather-driven shortage of available charger-hours.
- EV owners who are also, incidentally, dumbasses.
There may be a smattering of other groups out there. I suspect that, as with regular gas cars, some people now own old, beater EVs that aren’t up to the cold weather. Some may have actually had some critical part fail, in the cold. Some may have simply had extraordinary bad luck.
But I think the first three cover nearly everything you are likely to encounter.
The vast majority of EV owners fall into Group 1, those who dealt with the cold snap with no particular difficulty. That’s where I fall, plugging in at home, at night, in an unheated garage. And not pushing my car to the limits of its range. I think I’ll include almost all Tesla drivers of all stripes in that group, no matter where they charge, as they tend to have enough public charging slots to handle demand. In any case, the people in Group 1 are just not newsworthy. So you won’t see them represented in stories on winter EV driving.
I guess the point that needs to be made is that there’s nothing about cold weather that makes it impossible, or even difficult, to drive an EV. I’ve been driving mine, just fine, through this recent cold snap.
Group 2 boils down to “there aren’t enough public car chargers to handle unusual demand”. Which in turn boils down to “it takes a long time to charge an EV, compared to filling a gas car”. Something that should not come as a shock to anyone who has given this even a moment’s thought. Long charge time has an absolutely irreducible minimum just from the basic physics of pushing around a lot of electrons, all at once:
Three factors lead to a surge in the demand for public charging-station hours during a cold snap. And so to a shortage of public charger-hours.
First, charging a cold battery takes longer. Sometimes a lot longer. That’s really not news, and its true for all types of batteries, including good old 12V lead-acid car batteries.
Here’s an actual, real-word of example of DC fast charging times for a fleet of 2012 Nissan Leafs. Leafs are pretty much bottom-of-the-heap in terms of maintaining battery temperature. But I think this is reasonably indicative of what you might see in a cold snap — charging times greatly increase as the battery temperature approaches freezing — 32 F, or 0 C.
Source: U.S. DOE, Idaho National Laboratories, Empirical Analysis of Electric Vehicle Fast Charging under Cold Temperatures, November 2018. Annotations are mine.
The longer each car takes, the fewer cars can pass through any given charger in a unit of time. And the greater the inconvenience when you find all slots already full at a given charging station.
Second, EV range decreases in the cold. This may increase the frequency of charging for some drivers. Range does fall, but only somewhat. (Virtually every statistic you will see, in the news, is somebody’s worst-case scenario, not an actual observed average). And that reduction is mostly due to use of passenger cabin heating, and so is partially within the driver’s control. Drivers can take other steps, such as pre-heating the car while its still plugged in.
Source: As reported on Kelley Blue Book (kbb.com).
In any case, people who routinely go from near-100%-charge to near-zero-charge will now have to recharge more frequently, to stay away from depleting their battery. So this adds to the demand for public-car-charger hours.
Finally, some charge-at-homes (Group 1) with unheated parking may find that they can no longer completely recharge their car overnight. That’s particularly true of those relying on the slowest (Level I, 120V) charging. If temperatures drop, and stay low, some people will find that their daily commute exceeds the ability of their home system to recharge the car in a single night, in the cold. It that goes on long enough, the battery gets close to depletion, and those people then seek out public fast-charging stations to make up for the home-charging shortfall, and further add to demand for charger-hours.
And so, if you are not a Tesla driver and depend on some sort of public charger, at present, you are going to be vulnerable in a cold snap. A charger network that barely functions in the best of times is going to get congested when individual car charge times triple (or so) in the cold. Along with other factors adding to public-charger demand. People who got caught out by that, and ended up with long waits for charger access, made up the bulk of what seems to have made the news reporting.
A brief interlude: Long lines for refueling your car? That’s un-American!
Above: Gas lines, 1970s Arab Oil Embargo (1973, mostly)
Following the 1973 Arab oil embargo, Americans routinely faced long lines for gasoline. As note above, most states implemented odd/even rationing (based on last digit on the license plate). Note the Nixon sign. As is true today, the stupidest among us blamed the (then-) President for it.
Above: Gas lines, evacuation for hurricane fill-in-the-blank (pick a year, any year).
Any time there’s a significant evacuation (e.g., for a hurricane), there are long gas lines, and the gas stations run out. This occurs like clockwork, even if the advance warning precedes the hurricane by days. This is so routine that below you see the first piece of advice that the FEMA offers, regarding evacuations:
Source: FEMA, Basic Preparedness.
I modified my home emergency preparedness to provide for spending a couple of days in the car. That, because the one constant of American weather-related disasters is that they generate massive traffic jams (Post #1620, Post #1625).
Above: Gas lines, Colonial Pipeline ransomware shutdown (2021). (Except the lady in the yellow jacked seems to have made it into this set, and the set above.)
And, of course, if there’s even a hiccup in key infrastructure, you end up with … long lines for gasoline. That can be a pipeline shutdown, an extended loss of electrical power, or even just a blip in demand that is more than supply chain routinely accommodates, as was the case for spot shortages of gasoline (and toilet paper) during the pandemic.
Above: Jump-starting cars, in winter.
Finally, cold weather does no favors for batteries of any sort. If you’ve ever been stranded by (or helped someone with) a dead car battery in the winter, you know that it takes for-ever to charge a cold 12V car battery. And lead-acid batteries have one of the more forgiving battery chemistries, when it comes to cold weather.
Group 3: People who don’t understand their EV.
That said, there’s still a group of people who managed to get caught out, in this last big freeze, mostly because they did something kind of dumb. And the complaints from those folks make great click-bait. So they get vastly over-represented in news reporting, compared to their actual prevalence in the population.
Here are three common ways that people seem to trip themselves up. And then complain about it publicly.
The guess gauge can drop rapidly, and that’s normal. EVs will show you a predicted amount of range left. This is the equivalent of the gas gauge on a standard car.
EV users uniformly dub this the “guess gauge”. There is a reason for that. To guess how far you can go, on a given amount of charge, the EV has to take your driving habits into account. That’s always backward-looking, that is, it’s based on how many miles per KWH you’ve gotten historically, in your recent trips.
For example, even two weeks after I bought it, the guess gauge on my Bolt continues to (appear to) violate the laws of conservation of energy. I’ll start with a given amount of range showing, drive a few miles, and end up with even higher range showing. That’s because it’s slowly forgetting its experience at the dealership — lots of sitting around with the heat on, lots of apparently fast driving — and slowly getting used to me (moderate-speed around-town driving). Eventually, the dealership experience will be forgotten, and the car will cease to appear to manufacture energy out of thin air.
When there’s a sharp change in anything effecting your mileage (miles per KWH of charge), the guess gauge will be wildly off. And as it catches up with current conditions, its guess may change pretty rapidly. (This depends on the particular car. At the extreme, by reputation, the Tesla guess gauge never reacts to anything, and is more-or-less just a state-of-charge gauge, translated to miles.)
And so, just as the guess gauge consistently understates my available range right now, it would consistently overstate available range at the start of a deep cold snap. It’s showing you how far you can go, based on how far you were able to go in normal weather. It takes it some time for the lower mileage, of the colder weather, to work its way into its algorithm.
If you drive an EV, and you don’t realize that, you could be in for some bad surprises. And so you find reports of people who said that the range of their car dropped rapidly as they drove. They think the car is behaving abnormally, when, in fact, this is merely the guess gauge catching up to their current energy use, and no longer making its prediction on their past energy use.
Sure, I can see where a novice driver might be confused by this. Might think the car is misbehaving. But mostly, you have to keep in mind that it’s called the guess gauge for a reason. You need to take it with a grain of salt, and you need to pay attention to additional information such as battery state of charge, and recent miles per KWH, to get a firmer grip on how much range you really have left.
Running low on charge is inherently riskier than running low on gas. That’s just the way it is, and you have to plan accordingly.
With a gas car, you rarely find every pump at any gas station filled; you typically have multiple choices of gas stations within range; and stopping for gas means literally one minute pumping fuel into the car. If one particular gas pump or even gas station is fully occupied, it’s no hardship to find another.
With an EV, you have far fewer choices of places to fuel up, and refueling is a far larger time commitment. In addition, because there are so few places, and because the non-Tesla charging network is so haphazard, you always face a non-zero chance that you won’t find an empty, working charger, despite what your app may be telling you.
It’s just a completely different ballgame. And until that changes, you’re kind of nuts to drive an EV as you would drive a gas car. Getting down to the last tenth on the gas gauge is no big deal. By contrast, driving until your battery is down to 10 percent state-of-charge is not smart at any time, least of all in extreme cold weather.
Stone cold, stone dead — that’s a no-no. There’s really only one rock-solid rule for driving an EV in winter. You do not want to find yourself with a totally dead, stone-cold battery. Ever.
If the weather is below freezing, but you’ve got some charge left? No problem, you can make you way to a charger, or to a warm garage. Not a problem. Just about out of charge, but it’s warm out? Again, not a problem, you can just limp along to get to somewhere you can plug in.
But if you get to the point where the battery is below freezing, and is out of charge, basically, you are stuck. That’s for two reasons.
First, the car will not allow you to charge the battery if the battery is below freezing. This is to avoid permanent damage to the battery due to “lithium plating”, or buildup of solid lithium material. Instead, EV batteries have internal heating elements, and these are actuated when you plug in to charge and the battery is cold. But if the battery is really frozen through, it can take a really long time to warm up enough to be charged at a non-trivial rate.
Second, if the batteries get really, really cold — like 0F or so, depending — that will permanently damage most Li-ion batteries. For that reason, I think most if not all EVs have fail-safe heaters that will come on and run, off the energy in the battery, if the battery gets close to those limits. But if there’s no charge left in the battery, those protective heaters will not run. My belief — though I’m finding it hard to document this — is that if you take an EV, drain the battery completely, and park it in extreme (sub-zero-F) cold, you’ll damage the battery beyond repair.
And so, if you kill the battery totally dead, you’ve removed that last line of defense. A totally dead battery, and really cold temperatures, is a combination that can, I think, effectively trash your car.
This aspect of EVs is completely unlike a gas car. In theory, as long as you’ve got the right antifreeze in everything, you can park a gas vehicle, cold-soak it down to extreme cold temperatures, and more-or-less nothing will happen. Warm it back up, maybe charge the 12V lead-acid battery, and it will start. By contrast, I’m pretty sure that if you take a totally dead EV, and leave it outside in extreme cold, you can damage the battery beyond use. It takes some serious cold to do that, but that makes EVs fundamentally different from gas vehicles for extreme-cold climates.
Summary
My Chevy Bolt is a refugee from the frozen north. It was first sold in Vermont. In fact, all the used EVs I looked at were “salt belt refugees”, in that all of them had been sold originally in cold climates, and shipped south for resale as used cars (Post #1919).
So I have no doubt that EVs work better in a more temperate climate. That’s what the used car market is telling me. And so, at present, they may not be a good choice for everyone, everywhere.
But winter just doesn’t matter to me, for driving a Chevy Bolt, in Virginia. I recharge at home, in an unheated garage. The car can stay plugged in until I need it. I typically drive with no heat, only the low-wattage heated steering wheel on. I don’t routinely use the entire range of the car. And I don’t even notice a reduced range when it’s colder out.
So in my case, all I can say is that the wintertime death of my EV has been greatly exaggerated. So far –for all two weeks of ownership — it’s probably the best used car I’ve ever purchased.
That’s boring. It’s nothing you’ll see reported in the news. But, I suspect, that’s the way it is not just for me, but for the overwhelming majority of EV owners.
The big issue that this recent freeze has highlighted is the poor state of the non-Tesla charger infrastructure. And the weird economics of it, in that you predictably need vastly more charger capacity during cold snaps. But only during cold snaps.
I have a feeling that it’s never going to prove economic to satisfy that transient demand. In exactly the same way that gas stations don’t keep enough gas on hand to satisfy the panic-buying that precedes an evacuation order.
Unless there’s some way around that, I think events like this most recent cold snap are going to be a real barrier to more widespread adoption of electrical transport in the cold-climate areas of the country. People depend on their cars. And, by inference, they depend on their car fuel infrastructure. Outside of Teslas, that network is already slipshod enough. If public car charging will predictably turn into a nightmare once or twice per winter, people in snow-belt states aren’t going to buy EVs.
And while I’m happy to benefit from a used-car bargain on account of that, I think that would be a step backward for the country as a whole.
