How EV drivers can maximize their range in the cold
JUANA SUMMERS, HOST:
I am not sure how many ways we can express the fact that it is just really cold in much of the country, but here's another one. In Chicago, electric vehicle owners are having a hard time with their car batteries. It is so cold that, if they reach a charging station before their batteries give out, they are facing long lines and slow charging times once they do plug in. So what gives? Why is it so hard?
Michael Crossen has spent a lot of time evaluating how EV batteries behave in extreme cold. He is an automotive technician with Consumer Reports' Auto Testing Center. He joins us now. Welcome.
MICHAEL CROSSEN: Hi. Thank you for having me.
SUMMERS: So Michael, if you could, can you just start by breaking down the challenge that these awful cold temperatures pose to EV batteries and their ability to charge?
CROSSEN: Yeah, it's definitely something that is certainly current, you know, with the weather that we're all having. And EVs tend to do worse in cold weather, mainly because of the need for heating in the cabin. Gas cars are less efficient in the cold, too, but it's less of a consideration because, you know, if we're getting a little worse fuel economy, when we run out of fuel or run low on fuel, we can stop and just fill up the tank pretty quickly. But all of the heat that we get inside the cabin is coming from the battery of the vehicle, so that is affecting our range. And in our testing here at Consumer Reports, we see anywhere from 25- to 30% reduction in overall range in colder temperatures, and a big portion of this is due to using the climate control in the vehicle.
SUMMERS: OK, so I have a question here. I don't drive an electric vehicle myself, but my neighbor does. And one of her constant complaints is the fact that she has trouble often finding places to charge her car. So I'm wondering, in places like Chicago, where we're seeing some of the biggest problems, how much of the issue is exactly that - not having sufficient charging stations?
CROSSEN: It's definitely a consideration for an EV driver. You know, if you can charge at home, if you have great charging infrastructure at home and maybe even at your place of work, it's probably a little bit of a - less of a concern. But if you're relying on public charging, it can be a bit of a roll of the dice. You know, you drive there. You use some of the maybe less range that you have. You get there, and maybe - of the six chargers, maybe two are not working. There's cars already charging. Maybe there's even cars waiting. So it can be a bit of a disappointment and definitely deserves some considerations and planning as an EV driver. You don't want to be on your way to work and realize that you need to charge, and now, you know, you're waiting for someone else to charge. And before you know it, you know, you're showing up to work three hours late because you had to stop and charge your EV.
So it's a bit of a different lifestyle. You definitely have to plan ahead and kind of be conscious of that. But it is something we're seeing here in Connecticut as well, so it's not just sort of a Chicago problem. And even places where, you know, they don't get the extreme weather, where it is a little bit, you know, more mild and warm, you can still run into those issues with the charging stations.
SUMMERS: I mean, listening to you talk about this, I'm a little hungry for some tips for drivers. What can people driving electric vehicles do to maximize their range?
CROSSEN: I would say the biggest thing you can do is, in the morning, when you're kind of getting things ready, leave the vehicle plugged in if you can. If you have a charger at home, leave it plugged into the wall as you're maybe clearing snow and ice off the car and do what they call preconditioning. You can either do this from the vehicle itself, or a lot of these EVs have an app that you might use off your smartphone. But basically, you're warming up the inside of the car and the battery, and that's key, too. The battery likes to be a little bit warmer than subfreezing temperatures. So the warmer that battery is, the more efficient that battery will be, and you kind of gain some range back - not to mention the electricity is coming through the plug, off the grid, to warm the vehicle up, so you're not pulling off of your available range to get that vehicle warmed up and melt some of that snow and ice.
The second thing is going to be precondition the battery before you DC fast-charge. Again, these batteries like to be warm, and fast charging is kind of strenuous on the battery. We're putting a lot of energy back into the car, and we want that battery to be as warm as possible. And through the infotainment screens on these cars, there's a preconditioning setting that you can do to prepare the vehicle for fast charging.
And the next two things you can do is try to lower the heat in the cabin. You know, definitely don't drive around with it off. You know, you want to be comfortable. You want to be safe. You want to be able to, like, defog the windows, but you don't need to ride around at 80 degrees. You know, think about, you know, kind of what temperature maybe you set a house to. You know, you don't want to have to be all bundled up either. You don't want to be freezing in the car, but you also don't need to be sweating. So pick a mild temperature - 72, 74, 76 degrees - and that will save a little bit of range.
And then this next one is for EVs in general, whether it's cold out or even warm out - drive a little bit slower. EVs become less efficient the faster you go. So at the highway speeds, they're less efficient than around town. So maybe just take five or 10 miles an hour off your speed, and you will gain a little bit of range back. And again, you just need to plan ahead so you leave enough time to get to your destination.
SUMMERS: That's Michael Crossen, an automotive technician with Consumer Reports' Auto Testing Center. Michael, thank you, and stay warm.
CROSSEN: Thank you so much. Transcript provided by NPR, Copyright NPR.
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