November is here, and you may have noticed that the weather is getting colder all the time. Cold weather brings various car-based challenges with it, and even the best electric cars are no exception to that.
The colder the weather, the less power you’re going to be able to get out of your car’s battery. Thanks to the laws of physics, batteries don’t do so well in the cold, and your range will likely suffer as a result.
That’s the bad news anyway. The good news is that you likely won’t experience much of a dip, and may not even notice any difference if you prepare your car correctly. But it’s still worth remembering the effects of cold weather on an electric car — especially if this is going to be your first winter without gas.
How does cold affect EVs?
If you paid attention in high school physics, you’ll already know that cold atoms move more slowly than when they’re hot. The colder the environment, the less energy is available and the slower those atoms move.
This is particularly important to remember where EVs are concerned, since cold weather makes it much harder for lithium ions to move between each side of the battery. So there isn’t quite as much power for you to draw from, which has a direct impact on your range.
As bad as that sounds, it’s not quite a full picture. For starters, automakers have developed systems to keep batteries as close to optimal temperatures as they can. However, as Consumer Reports notes (opens in new tab), you also have to take into account the fact that heating systems (including the ones inside the cabin) have to rely on that very same battery for power.
In other words it’s a balancing act between losing range to cold, and losing range because your battery has to keep both the car and yourself warm.
How much range will your EV lose in the cold?
There are a lot of factors that affect total EV range, and temperature is just one of them. However putting a figure on that has led to some debate.
AAA (opens in new tab) has previously warned that you could lose as much as 41% of your total battery capacity in temperatures around 20 degrees Fahrenheit (-6 Celsius). Meanwhile Consumer Reports has pegged the figure closer to 50%, though neither of them is particularly comforting.
On a more optimistic note, the Norwegian Automobile Federation (opens in new tab) (NAF) did some testing with 20 different EV vehicles and discovered the average drop is closer to 20%. What’s more, the cars themselves made it perfectly clear when they were low on power, so drivers had plenty of warning when the car was due for a recharge.
Norwegians are pretty big fans of electric cars, and have been before the trend took off elsewhere. Considering temperatures can drop well below freezing in the winter months, EVs would not be as popular as they are if cold had such a considerable impact on range.
How to optimize EV range during winter
While winter isn’t an automatic death sentence for EVs, you will end up getting less mileage out of your car. That’s just how it is. Thankfully there are things you can do to try and maximize your range, and make sure your power economy doesn’t take a nosedive when it gets a bit frosty.
Don’t let the battery get too low: Automakers know lithium batteries don’t function as well in the cold, so any EV worth its stuff will have thermal management systems in place to keep everything running optimally. However this requires power, and typically an EV will keep around 15-20% in reserve to keep the battery warm.
It’s already good practice to keep your EV battery over 20%, since letting the charge get too low can speed up battery degradation. However it’s especially important in cold weather if you want to keep yourself moving.
Dump your excess weight: The heavier your car, the more energy is needed to move. This is true at any time of year, but it’s just as important to remember during the colder months when you’re already at a disadvantage. So be ready to dump all the unnecessary weight to get as much range out of your car.
Park inside if you can: If you have access to a garage then you’re going to want to keep your EV parked inside and away from the elements during the winter months. They may not be the warmest places around, but it’s a heck of a lot warmer than out on the street or the driveway. That warmth will help your battery charge faster and maintain that charge for longer.
Likewise, using a covered parking garage, rather than an open parking lot or street bays, is the best option if you’re out and about.
Heat up your car before you leave: While EVs don’t have engines, and don’t need time to warm up on particularly cold days, it does help to warm up the cabin before you leave. Not only will that make your trip a lot more pleasant, some of that heat will warm up the battery and improve its performance.
If you can, do this while your car is plugged in, so your battery doesn’t take a hit before you leave. Likewise, if your car has a companion app with remote access, use that to turn on the heating ahead of time. That way you’re not sitting around waiting for the car to heat up.
Avoid the heater when possible: A gas-powered engine produces a fair amount of heat during use, and that is exploited to heat the cabin when needed. EVs don’t have engines, and don’t have that same luxury, so it essentially has a built-in space heater that taps into your battery reserves — lowering your overall range in the process.
If your car has a heated steering wheel, heated seats, or anything else along those lines, use them instead. They don’t use nearly as much power and that means preserving all those extra watts for increased driving distance.
Check your tire pressure: While not unique to EVs, it’s important to make sure your tires are prepared for the winter months. The most important thing is to regularly check the tire pressure. Colder air contracts, which reduces the internal pressure, and increases resistance on the road. Minimizing resistance and drag is essential for maximizing range.
You may also want to invest in some winter tires, especially if you live in an area with a lot of snow. Winter tires will lower your range, thanks to the increased grip and low rolling resistance, there’s no avoiding that. But by finding tires with the right balance between the two means you’ll be able to optimize your winter range while still keeping a nice safe grip on the road.
Turn on Eco-Mode: If your electric car has a dedicated eco-mode, you should make sure to switch that on if it's not already. Eco-Mode is an important part of maximizing range at the best of times, since it reduces power consumption across the board.
This means your acceleration will be slower, and power-hungry features like the heater won’t be as powerful, but it does translate to more drivable miles. And in winter, with everything else working against your total range, that’s even more important.
There are advantages to cold weather EV driving
While EV range can take a hit during the winter months, EVs themselves do offer a few advantages compared to your typical gasoline-powered vehicle. The main one being that you can usually switch on the heater when the car is still plugged in, so you can leave home with a full battery. Remote starting is very common on EVs too, which adds to this.
The fact EVs don’t have an exhaust means you can keep it running in an enclosed space (like your garage) without turning it into a major safety hazard. Electric motors also don’t need warming up, in the same way an engine does, so you don’t have to worry about making sure everything is warmed up before leaving home — even if it is a good idea to get some heat on for the battery.
However the main benefit is in the driving. EVs don’t have gears, meaning power is applied quite smoothly while you’re driving. This is beneficial in slippery conditions, and means you’re not as likely to slip or skid while accelerating in icy or snowy conditions.
Likewise regenerative braking can also prove useful at smoothly slowing your car down — which is a boon when the roads are slippery. The only downside is that regenerative braking, even on cars with one-pedal driving systems, is not as powerful as the actual brakes, so it’s usefulness is a little bit more limited.
- Plus: Electric car tax credits: What you need to know about EV financial incentives