Driving an EV
Does Driving Range Decrease in Cold Weather?Written by Larry Thompson The short answer EV batteries operate and charge most efficiently when the battery and ambient temperatures are about 70 degrees Fahrenheit. According to a 2019 AAA study* driving when ambient temperatures are very cold (e.g. 20 degrees Fahrenheit) can reduce driving by as much as 41%, especially when using the cabin heater. Fortunately, we don’t have 20-degree temperatures in Connecticut very often and there are simple things you can do to mitigate possible range reduction such as: 1) Heat or cool your vehicle while it’s still connected to the Level 2 charger. Most EV’s today have a phone app which allows you to remotely control the heating and cooling system. Turn the heat or cooling on before you get in the car and you’ll have a nice comfortable car without reducing the driving range. 2) The cabin heater is energy-intensive so many EV owners will use the seat heaters and supplement the heat as necessary with the cabin heater. 3) Driving even 10mph slower than normal may significantly alleviate any range reduction due to cold weather and actually in any weather. 4) Underinflated tires reduce the driving range in all temperature conditions. In cold weather, tires can lose up to 1-2psi for every 10-degree drop in temperature. * https://www.aaa.com/AAA/common/AAR/files/AAA-Electric-Vehicle-Range-Testing-Report.pdf Learn more Also, note cold batteries cannot accept as much energy or as quickly as warm batteries. Therefore you may experience a reduction in the regenerative braking capability in your EV during that state. https://insideevs.com/features/342917/cold-weather-electric-car-tips-maximize-your-ev-for-winter/ https://www.chargepoint.com/blog/5-tips-ev-driving-cold-weather/ https://www.greenenergyconsumers.org/drivegreen/winterdriving
Written by Larry Thompson
(Updated March 2, 2020)
The short answer
Range anxiety is a term used to describe a concern the car will run out of battery capacity before reaching a charging station. The term was prevalent in earlier days when BEV driving range was limited and charging stations were few and far between.
Most new BEV’s have a driving range in excess of 220 miles which is generally sufficient for daily driving and the BEV will usually provide visual and audible warnings as the battery capacity becomes low. The longest range BEV currently available, the 2020 Tesla Model S, has a range of 390 miles. There are several vehicles expected to be available in the near term that will be 300+ miles.
PHEV’s are not subject to range anxiety as they have an internal combustion engine that can power the car separately from the battery system.
Upon acquiring an EV, you will quickly learn several tips for maximizing range. These include pre-conditioning the car while it is still plugged-in and using the heated seats instead of the cabin heating if it is not inordinately cold.
According to the US Department of Energy* there are approximately 366 public charging stations with 937 outlets in Connecticut. Tesla reports** a total of 18 Supercharger stations with 124 outlets and 7 additional stations planned.
Some BEV navigation systems can automatically plot a route to the nearest charging station when the battery capacity gets low.
Most EV’s have a portable charging cable that can be plugged into a 120 volt outlet, although the charge rates for 120 volt systems are slow, generally around 3-5 miles of charge per hour.
Updated March 5, 2020
How far can I drive an EV?
Written by Larry Thompson
The short answer
Most EV’s today have a driving range between 120 and 370 miles per charge. Given the average drive of 40 miles per day even EV’s at the lower end of the driving range should be suitable for daily driving assuming the car can be charged each day or two.
For trips longer than the EV’s estimated driving range owners will want to plan to stop at a charging station in route to their destination. (see the How Do I Charge my EV When Travelling? question).
Battery Electric Vehicles (BEV)
It’s important to remember that the manufactures driving range estimate is based on a set of predefined conditions that may or may not reflect your actual driving conditions. Factors that typically reduce driving range are 1) driving speed, 2) repeated and aggressive acceleration, 3) ambient temperature, 4) using the cabin heater or seat warmers and 4) towing trailers or other cars.
EV batteries operate and charge most efficiently when the battery and ambient temperatures are about 70 degrees Fahrenheit. Driving in ambient temperatures in the mid to low 30-degree range can reduce driving by up to 20-25%. Using the cabin heater will significantly reduce range, although seat warmers used in place of or in conjunction with the cabin heater is a more energy-efficient to stay warm in colder conditions.
EV batteries also charge faster in moderate ambient temperatures as the battery needs to be in a prescribed temperature range before optimal charging speeds can be obtained. Some EV’s automatically warm the battery when the EV’s navigation system is plotting a route to a charging station. See the “Will I lose driving range in the winter?” question for more range issues in Winter driving conditions.
Most EV’s have high efficiency LED headlights which do not noticeably reduce driving range.
Plug-in Hybrid Electric Vehicles (PHEV)
The above applies to battery electric vehicles (BEVs). Plug-in hybrids, which have a smaller battery pack along with a gas tank, do not have this constraint. Once the battery is depleted, the vehicle will automatically switch over to the gasoline engine. These vehicles do not all work in the same way. To conserve battery, some of these vehicles will engage the engine going up a steep hill or at high speeds even if there is charge remaining.