Extremely cold temperatures can decrease electric vehicle operating range by 41 percent, according to a new report by the American Automobile Association. The excess battery drain results primarily from using the vehicle’s HVAC to warm the vehicle interior.
High temperatures that require greater effort by an EV’s air conditioning system also shorten driving range, but keeping passengers warm when it’s below freezing has the greater effect.
AAA compared average operating range and fuel economy among five electric vehicles at 20 degrees and 95 degrees Fahrenheit to their performance at 75 degrees, a moderate temperature at which the vehicles had the highest range and fuel economy.
Even when the EVs were run without using their HVAC systems, operating range and fuel economy dropped, but not as drastically as when the heating or cooling systems were employed.
At 20 degrees Fahrenheit, the average driving range decreased 12 percent and fuel economy dropped nine percent; both compared to 75-degree temperature operation. With the HVAC systems in use, however, the tested EVs’ average driving range decreased 41 percent and fuel economy fell 39 percent at 20-degree temps.
At an above normal 95 degrees, running with no air conditioning cut the range by four percent and fuel economy by five percent. When the AC was turned on in 95-degree testing the range decreased by 17 percent and fuel economy slipped 18 percent.
AAA has four recommendations to help owners prepare for EV’s reduced driving range and lower fuel economy before driving when the weather is colder or hotter than usual:
- Account for the lower driving range and plan for more charging stops than usual. Check the locations of charging station along your route before beginning your trip.
- Reduce the EV’s effort to bring the cabin to a comfortable temperature range by pre-heating or pre-cooling while connected to a charger.
- Park the EV in a garage.
- Get used to planning if you own an EV in areas in the U.S. with frequent extreme temperatures, especially in states with long, cold winters.
AAA tested five electric vehicles in conjunction with the Automotive Club of Southern California’s Automotive Research Center (ARC) in Los Angeles. AAA selected one vehicle per manufacturer, with the requirement that the EVs were sold in the U.S. and had a minimum 100-mile EPA estimated driving range. The test vehicles included a 2018 BMW i3s, 2018 Chevrolet Bolt, 2018 Nissan Leaf, 2017 Tesla Model S 75D, and a 2017 Volkswagen e-Golf.