Cold Weather Reduces Range
One of the most common questions about electric cars is how much cold weather affects their range. It’s true: temperature can have an effect on the performance of EV batteries – just like our mobile phones and other electronic devices. It’s also true that all cars – no matter what they are powered by – have less range in cold weather. But reduced winter range is more noticeable in an electric car, because they take longer to “fill up” than a gasoline vehicle – potentially making the reduction more of an inconvenience.
Why do electric cars lose range in the winter? Like in all batteries, chemical reactions occur more slowly in cold temperatures. Lower temps inhibit chemical reactions, and act as increased electrical resistance. This slows down physical processes – so you need more electricity to perform the same amount of “work” like accelerating the car.
Also, electric vehicles have to generate their own heat. A gasoline vehicle bleeds off excess heat that is generated by the internal combustion engine to warm the cabin – this shows just how inefficient gasoline vehicles are, but you essentially get heat “for free.” On the other hand, the much more efficient electric motor in an EV doesn’t generate nearly as much heat. The heater in an electric car actually has to draw additional power from the battery to warm the cabin. And in fact, in some conditions, battery power must be used to heat the battery itself, to maintain performance. All of this reduces the amount of available battery power left for actual driving.
So, you can expect winter weather to affect the amount of range you get from an EV. But do some models perform better than others in the cold? Some new data from EV-industry watcher Recurrent Auto helps give electric car shoppers in colder climates some guidance. They analyzed several popular EV models to show range loss in different driving conditions, using aggregated data from thousands of vehicles across the U.S.
Which EVs Performed Best in Winter?
The top EV range performers in winter were all high-end crossovers with large batteries. Tied for third place were the mid-size Tesla Model Y Long Range and the larger Tesla Model X 75D, both of which lost 15 percent of their range in winter conditions (20 to 30 degrees Fahrenheit) versus regular conditions (70 degrees Fahrenheit). In second place was the Audi e-tron Premium Plus, which lost just 8 percent of its range. And top spot went to the Jaguar i-Pace, which was remarkable for only dropping 3 percent of its range in cold conditions.
Why did crossover EVs with all-wheel drive and large batteries perform well? For one thing, their driving behavior in cold, slippery conditions and on dry roads is similar; unlike two-wheel drive EVs, their twin-motor setups don’t have to work that much harder in the winter. But more importantly, a larger battery suffers less on a percentage basis when some electricity is bled off to heat the cabin – the impact of a few kWh of usage is far less on a 100-kWh battery than on a 50-kWh battery.
All three of the top performers also use a heat pump to warm the cabin without imposing as much of a drain on the high-voltage battery. Heat pumps recapture and store waste heat from the motor in warmer conditions. All of the top performers also have energy-efficient standard heated seats, which warm driver and passenger bodies faster and more effectively than warming the air in the cabin.
Why Do Some EVs Lose So Much Range?
Which electric cars lost the most range in the winter? In third place was the BMW i3. It’s a compact, rear-wheel drive city car. With a small 42-kWh battery and no heat pump, it lost 24 percent of its range in winter compared to more temperate conditions. Tied for second-worst were the Volkswagen ID.4 and the Ford Mustang Mach-E. Both vehicles do not come with a standard heat pump, and lost 30 percent of their range in the winter. The worst performer was the Chevy Bolt, which has a relatively small 60-kWh battery and no heat pump; its winter range was 32 percent below its summer range.
Recurrent’s study says that the Bolt is highly sensitive to temperatures, and the available range can drop significantly even in relatively mild conditions. On the other hand, the Bolt’s EPA-rated range of 250 miles is one of the best in its class, so even with the degradation, it is one of the longest-range small cars.
How to Improve Your Range
If you’ve decided on an electric car and live in a colder climate, Recurrent’s range data can help you choose the right car. But there are good driving practices that will help you extend the range of any vehicle.
By adjusting your driving style – accelerating more gradually, and easing off the accelerator when you see traffic bunching up ahead – you can eke out many more miles from every change. Slowing down your cruising speed by even a couple of miles per hour will also help significantly.
Check that your tires are in good condition and at the correct pressure. Use the seat and steering wheel heaters, if installed, instead of the cabin heater, and you can find a few more miles as well. And for more tips, we have a full article here on GreenCars with detailed information.