I drive a 2020 Chevy Bolt electric vehicle. No matter what time of year, everyone asks if I get less range in the winter. I get a little less, especially if my kid cranks up the heat. But it’s really not a problem. I have way more range than I need for regular driving. We can go skiing to Kelowna with a couple of 20-minute stops at a fast charger and, for normal driving, I can fill up in my driveway. Here’s my question: People who don’t drive EVs worry about them losing range in winter, but don’t gas cars have worse fuel economy in the winter too? – Danielle, Vancouver
Whether you drive gas or electric, your range and fuel economy will suffer in winter.
“Gas cars lose range just like electric cars; you’re consuming more fuel in winter than in summer,” said Yves Racette, a Quebec-based consultant who specializes in training automotive technicians about EVs and hybrids. “Your gas mileage is really affected in winter, but people are so used to putting in gas that they don’t really think about it.”
Cold temperatures, snowy roads, softer winter tires and blasting the heater in the cabin can all make your car work harder and use more energy, regardless of what powers it.
To put it simply, when we talk about fuel economy in Canada, we’re talking about fuel consumption: how much fuel your car consumes to go a certain distance. It’s measured in litres per 100 kilometres for gas-powered vehicles and kilowatt hours (kWh) per 100 kilometres for electric.
Range describes how far you can go on a full tank in a gas-powered car or on a full battery in an electric car.
While it varies by vehicle and how you drive, gas-powered cars are about 15 per cent less efficient at minus 7 degrees Celsius, while EVs can be up to 40 per cent less efficient, according to the U.S. Department of Energy.
The DOE doesn’t calculate winter range on gas cars, but if you’re using more gas, you won’t get as far on a full tank.
For EVs, estimates vary. The DOE says you could see up to 41 per cent less range on a cold day – but about two-thirds of that is for heating the cabin.
On electric vehicles, batteries start losing range above and below about 21 degrees Celsius in part because of battery chemistry. But there are a number of other reasons.
Blasting the heat on cold days or the air conditioning on hot days are the biggest range thieves. In fact, if you’re not using the heat, you’re only losing about 12 per cent EV range at minus 7 degrees compared to a warm day.
That’s why experts suggest using the heater in an EV in short bursts, to set the temperature a little lower or rely more on heated seats.
Again, that varies by vehicle. EVs with heat pumps use less power to heat the cabin. But they only work if outside temperatures are above minus 15 degrees, Racette said.
Racette said he sees less range in his EV in the winter – but it’s still more than he needs for daily driving.
“I have a Ford Mach-E. In summer, I get 450 to 475 [kilometres] in range,” Racette said. “The first winter, I had about 270 kilometres in range. //But the second winter, after over-the-air updates, I got 320 kilometres.”
That increase was possible because some EVs have the potential for more range than the numbers shown on the dash, Racette said.
“There’s always a part of the battery they’re not using,” Racette said. “Look at how Tesla suddenly increased the range in Florida during the hurricane there a few years ago.”
If you’re taking mostly shorter trips – less than five kilometres – in a gas car in the winter, you’ll see a bigger drop in fuel economy than just 10 to 20 per cent. You could see a drop of up to 33 per cent.
That’s because it takes a while for engine oil and other fluids to warm up on cold days, the DOE said. Your engine needs time to warm up to more fuel-efficient temperatures.
Natural Resources Canada (NRC) lists other reasons too. Winter gas has slightly less energy per litre. The alternator has to work harder in winter to keep your battery charged. And using the heater fan, defroster and heated seats all draw power too, as does using all-wheel drive or four-wheel drive.
Also, if you leave your engine idling for more than 30 seconds to warm it up before driving, you’re wasting gas.
Just ten minutes of idling could burn up to half a litre of gas, NRC said. Instead, you could be warming up your engine while you’re driving – and actually get somewhere.
You can also use a block heater on a timer set to go on two hours before you need to drive.
Winter a drag on all cars?
Winter tires and deep snow both increase resistance, so your vehicle has to work harder and use more fuel, whether it’s electric or gas, Racette said.
Plus, colder air is denser, which means there’s more drag on your vehicle, especially at highway speeds, the DOE said.
Even if you don’t use winter tires, tire pressure drops as it gets colder. If your tires aren’t inflated to what your car manufacturer recommends, there will be more resistance and you’ll get worse mileage.
Transport Canada recommends checking pressure monthly, even if your car has a tire pressure monitoring system (TPMS).
[Losing range and efficiency in winter is] not just an EV problem,” Racette said. “It’s a problem for everyone – but if you drive a gas car, you might only notice when gas prices are high.”
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