The 2018 Chevrolet Bolt EV can travel more than 200 miles on a single charge — weather permitting. (CHEVROLET)
GM claims the Chevy Bolt gets 238 miles per charge. Here's why that's misleading
By PETER HOLLEY
The Washington Post
As the first vehicle to travel more than 200 miles on a single charge, the Chevy Bolt has quickly become electric royalty.
The vehicle’s mainstream success, which includes being named Motor Trends Car of the Year in 2017, has quieted skeptics and prompted General Motors to fully commit to an all-electric future.
But as automakers like GM tout the increasingly impressive distances their electric vehicles can travel, many consumers may not be aware that peak numbers are heavily dependent upon ideal weather conditions — such as southern California’s warm climate.
The Bolt can travel nearly 240 miles on a single charge, according to General Motors. The company claims some drivers have traveled 300 miles with the same amount of battery power.
But according to driving tests conducted by The Washington Post, that number can easily drop 100 miles or more depending on road conditions, individual driving style and — perhaps most importantly — cold weather.
Despite the disparity, the Environmental Protection Agency, which tests the range of all EVs on American roads, does not dispute GM’s numbers. Yet both GM and the EPA admit those numbers can vary significantly depending on the outside temperature.
On its website, the EPA says the range estimates are a “general guideline” for consumers.
“For any electric vehicle, range will always depend on several factors like weather, driving conditions, temperature preferences in the car, and overall driver habits,” Joe LaMuraglia, a Chevrolet spokesman, said. “To alert customers of potential range in real time while driving, driver information center includes a confidence gauge which displays high and low range estimates for the remaining battery life. There are also three in-vehicle energy screens available to monitor energy usage.”
In colder climates, as many EV drivers quickly learn, low temperatures are the enemy of range. Electric motors use energy far more efficiently than internal combustion engines but generate heat more slowly in low temperatures, forcing an EV battery to use some of its own energy to generate power, according to the Union of Concerned Scientists, a science advocacy nonprofit. EV range drops even more when you combine cold temperatures with abundant heater use, fast driving, quick trips multiple times a day and conventional breaking (instead of regenerative).
Over the course of several cold weather driving days, a Bolt tested by The Post nearly ran out of power after about 140 miles of driving, nearly 100 miles less than engineers expect from the car under more favorable conditions. That number improved by about 20 miles when the Bolt was driven in a setting that uses regenerative braking, which allows the vehicle to recover electric power each time it slows.
The lower range is not entirely surprising, according to Michael Lelli, the Bolt’s Chief Engineer.
“If the car was aggressively used in very cold weather and never plugged in, then it’s possible you’d see the range decrease the way you did,” Lelli explained. “When the weather warms up and heaters are used less and you employ strategies to make the driving more efficient, you’d see the vehicle move back up to the 230- or 240-mile range.”