Monday, February 19, 2018

Electric Vehicles Do Work in Cold Weather

Electric cars do work in the cold.  Their driving range decreases in the cold, as is the case for all cars — because physics.  However, they still function fine, and you can also pre-heat many of them.

Charging in snow (Image Credit: Nissan) Click to Enlarge.
Critics of electric vehicles sometimes mistakenly or misleadingly try to dismiss electric vehicles by claiming that they don’t work in cold weather.  This view is quite untrue and easily proven incorrect.  All EVs operate in cold weather.  But their driving ranges do decrease to varying degrees in cold weather.

For example, the Tesla Model S 70D reportedly experiences a loss of about 19% in driving range in deep cold (0°F with the heater on), according to a post made by the Union of Concerned Scientists.  If you read the Tesla forums, some posters have written that on winter days in Chicago, they have experienced up to a 50% reduction in range.

That figure may be for multiple short trips.  One poster wrote that for longer trips in cold weather his driving reduction was about 20–30%. This figure is in line with what a Nissan LEAF owner in Colorado wrote in a blog post about his experiences driving in cold weather there.   “This means that in cold weather (15°F), you get about 20% less range, even though you could heat the battery to room temperature with just 0.5 kWh (under 2%) of its energy.  Or simply use wall power when it’s plugged in.  A 20% penalty in cold climates to avoid adding a $100 heater.  Why!??!”

He also generously listed some of the benefits of having an EV in such weather:
The electronic traction and stability control systems work much better with an electric motor, because it can be controlled more precisely.  In practice this means that while a normal car would dig itself into a rut, the Leaf applies just enough power to get through the snowbank.  Or it stops the wheel, giving you a chance to reverse and give it another go.
  • There’s no cold-cranking worries or waiting for a cold engine to warm up.  You press the button, the car is on, and cabin heat is instantaneous.
  • The heated seats and steering wheel make the experience even more luxurious (and reduce the need for cabin heat).
  • Remote heating with an in-dash timer or from an app on your phone means your car can be heated and defrosted (or cooled in summer) before you even reach it in your driveway.  Without even consuming battery power, if you have the car plugged in.
  • Big wheel diameter, low center of gravity and 50/50 weight balance make for better handling and traction.
  • Front-wheel drive prevents fishtailing, and is every bit as safe as all-wheel drive.  Adding snow tires in winter turns the Leaf into a monster snow crusher.
People who are on the fence about getting EVs might feel that old issue of range anxiety anxiety rising when they hear about reduced ranges in cold weather.  However, gas-powered vehicles also have lower fuel efficiency in cold weather.  “Fuel economy tests show that, in short-trip city driving, a conventional gasoline car’s gas mileage is about 12% lower at 20°F than it would be at 77°F.  It can drop as much as 22% for very short trips (3 to 4 miles).”

So, reduced energy efficiency in cold weather is not only an issue for electric vehicles, but EV critics will probably not mention this fact — or they are not aware enough to mention it.

Read more at Electric Vehicles Do Work in Cold Weather

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