How to Maximize Winter Performance

How does an electric vehicle perform in cold weather? Is it reliable? Of course—just ask the people of Norway, where over two-thirds of all new vehicles sold are electric.

There are pros and cons to driving an electric vehicle compared to a gas-powered engine, but nothing disqualifies them from performing reliably in cold weather. Anyone who drives with an ice scraper, shovel, and sand in their trunk knows that winter driving requires extra preparation and forethought. EV owners are not exempt from that rule.

Battery and Range

If you’ve ever woken to a cold morning and found that the battery is dead on your gas-powered vehicle, you may be worried, does the same thing happen to an electric vehicle?

Most electric vehicles use a 12-volt lead-acid battery to start the car, but starting an EV is much simpler and uses much less power than starting a gas-powered car. The battery in a gas-powered car has to turn over an engine, getting pistons pumping in oil that has turned viscous in the cold. The same battery in an EV just needs to start a few electronics. Electric vehicles are more reliable than gas-powered ones in terms of starting in the cold.

Just like an internal combustion vehicle, fuel efficiency declines in the winter. According to the U.S. Department of Energy, the fuel efficiency of a gas-powered vehicle declines between 10% and 33% at 20 degrees F, compared to temps at 77 degrees F.

Efficiency varies by model, of course, by the type of driving one does, and by whether or not the cabin heater is used. For drivers who warm up their vehicles before starting their trip, fuel efficiency is even worse, since their gasoline car is going nowhere.

For an electric vehicle, laboratory-based tests conducted in February 2019 by the American Automobile Association (AAA) determined that driving range decreased by 12% at 20 degrees F, compared to temps at 75 degrees F. When the cabin heater was used, the loss of range increased to 41%.

However, a more comprehensive study of 20 vehicles, done in real-world winter driving conditions in 2020 by the Norwegian Automobile Federation (NAF), found that EVs lost an 18.5% range on average, with some of the more recent models losing only 9%. These figures included climate controls maintaining a comfortable cabin temperature.

Climate Control and Range

For EVs, the main reason for decreased battery range in winter is cabin heating. While gas-powered vehicles draw heat from the engine in order to heat the cabin, EVs need to use electricity from the battery, resulting in greater fuel consumption compared to gas-powered vehicles.

Yet it’s important to compare apples to apples: Even if an EV loses 41% of its available electricity while using its heater in cold weather, as in the AAA study, a gas-powered vehicle loses even more of its available energy year-round, just by running the engine. Depending on the model, 58% to 62% of the energy available in gasoline is wasted as heat in the combustion process, with only a small percentage of that recaptured to heat the cabin in winter. Above everything else, this is what makes EVs more fuel-efficient than gas-powered cars, even in winter.

Many EV models include fuel-efficient heat pumps for cabin climate control, decreasing the range loss by 3 to 5 times, according to the EV charging station company ChargeHub. Some also offer a “cold weather package” that pre-warms the battery and provides higher-powered heating when the vehicle is plugged in, among other options. As the Norwegian study notes, some of the vehicles it tested came with these cold weather packages and heat pumps.

Charging Rates

For the same reason that driving range decreases in an EV in cold weather, charging speeds do as well. While drivers might not notice any difference if they’re charging their car in a protected garage with an insulated EV charger, at higher charging speeds and in colder temperatures (such as at a public DC Fast Charging station), basic physics reduces the conductivity of batteries, slowing down charging rates.

The same applies to regenerative braking (“regen”), which returns some of the vehicle’s forward momentum into electricity and sends it back into the battery. In colder weather, regenerative braking will only send store electricity once the battery reaches a certain temperature.

Driving and Handling

As with gas-powered vehicles, EVs come in front-wheel drive, rear-wheel drive, and all-wheel-drive models. According to Consumer Reports, however, using snow tires “provides the best grip and assurance for going, stopping, and cornering no matter what you drive: all-wheel drive, front-drive, or rear-drive.”

Electric vehicles are on average heavier than comparable gas-powered cars, due mostly to the weight of the battery. Most EV batteries are placed at the base of the vehicle, lowering their center of gravity and increasing their traction and stability on slippery roads. (Once sliding, however, a heavier vehicle may be more difficult to control.)

Electric vehicles often come with an “eco” mode, which increases the efficiency of the vehicle, usually by engaging regenerative braking automatically and reducing the power output of the motor. While some experienced EV drivers recommend turning off regenerative braking under slippery conditions, in fear that the brakes will lock up, anti-lock braking works the same way with regenerative braking as it does with disc braking. Reducing the power output of the motor is like using a lower gear in a gas-powered car in order to increase traction.

Cold-Weather Tips for EV Owners

• Preheat your electric vehicle. Most EV charging is done overnight, so most EV owners have the option of pre-heating their vehicles while the car is still plugged in. Most EV apps allow you to control the cabin climate remotely so that you can set the heater to turn on 10 to 15 minutes before you unplug the vehicle and drive away. This way, you are using grid electricity to heat your vehicle, rather than the car’s battery. You may then be able to keep yourself comfortable by relying solely on the seat heaters and steering wheel heater, which use far less electricity.
• You can also use your app to time your charging session so that it ends just before you leave on your trip. That way, the battery is already warm from charging and will be more efficient.
• Use one-pedal driving. Approach a stoplight by removing your foot from the accelerator and allow regenerative braking to slow the vehicle down, then only use the brakes to bring the car to a full stop. You will only regenerate a little electricity, but you won’t wear your brakes down as quickly.
• If you’re charging on the road, have a backup plan. You can use a phone app like PlugShare to see if and where public charging stations are available, but that doesn’t necessarily mean that the parking spaces have been plowed.
• As with a gas-powered vehicle, maintain the recommended air pressure in your vehicle’s tires. Cold air takes up less space than warm air, so tires in cold weather lose about 2% of their air pressure for every 10 degrees F drop in temperature, increasing their rolling resistance and decreasing efficiency.
• Slow down, especially on the highway. While electric vehicles are far more fuel-efficient than gas-powered vehicles, that increased efficiency is more pronounced in city driving than on the highway. An EV uses almost no electricity when stopped in city traffic, unlike a gas-powered car, whose engine is still burning fuel when “idling.” EVs are less efficient at converting chemical to electrical energy at higher speeds than at lower speeds. On highways, you’re not only using more electricity, you’re using it less efficiently.