Electric Vehicles in the Wintertime

The Ford Fusion performs well on a snowy road in Vermont. Courtesy photo.

David Roberts

Many recent car buyers are discovering the benefits of getting plug-in electric vehicles (EV), including:

• They have great performance and are fun to drive;
• They are cleaner than gasoline options – even factoring in upstream emissions of electric generation; and
• Federal, state, and utility incentives can bring purchase prices down significantly. Over the life of a vehicle, they can save thousands through lower fuel and maintenance costs.

We’re enthusiastic EV advocates at Drive Electric Vermont, but it is important to understand how cold temperatures may reduce battery range to make an informed purchase. Below are some tips on picking the right EV model, model options and operating practices to maximize cold-weather performance.

Winter Range EV Purchase Considerations

Cold weather reduces efficiency of all vehicle types, not just EVs. According to FuelEconomy.gov, conventional gasoline vehicles typically have a 20% reduction in fuel economy at 20° F. However, it is often more noticeable with an EV and is especially concerning for all-electric vehicle drivers who need to know they have enough range to reach their travel destinations.

Keeping the inside of the vehicle warm in winter is usually the biggest drain on EV range, especially when ambient temperatures plunge below 15° F. Lithium ion batteries used in EVs also do not perform as well in cold temperatures, which can lead to further range reductions.

The team at fleet analytics company, Geotab, analyzed thousands of EVs in varying conditions and developed detailed data on expected EV range reductions in cold conditions. Their general findings are that at -4° F, drivers of an average EV might see about half of the manufacturer’s estimated range. However, this varied significantly depending on the model, and how it is stored and operated. Their online EV temperature tool allows users to check the potential cold-weather performance of specific models.

Getting through the winter in your EV begins with purchasing the right vehicle for your needs. Most new all-electric models offer more than 200 miles of “official” range, so even with winter reductions, many drivers will rarely be inconvenienced by these issues. On the other hand, older used EV models may offer less than 100 miles of official range which can present significant challenges if drivers aren’t aware of winter reductions when purchasing.

If you have a long commute or are a winter road tripper, we recommend longer range all-electric models or plug-in hybrids that can run on gasoline for extended range. For long distance travelers wanting to go all-electric, Tesla’s proprietary fast charging network and navigation systems greatly simplify route planning. States and automakers are building out more non-Tesla fast charging along key routes, but Tesla has a significant lead in this effort.

We also highly recommend purchasing EVs equipped with cold weather options offered by many automakers, including heated seats and steering wheels. These are much more efficient than running cabin heating systems. Some EV models may also have battery heaters that help keep the battery pack at optimal temperatures. Several automakers offer more efficient heat pump heating systems that can significantly improve cabin heating efficiency down to about 15° F. The list below details model-specific cold-weather options for many current 2019 or 2020 model year vehicles.

• Audi e-tron includes a heat pump as standard equipment, but also offers a cold-weather package with heated rear seats and a higher-powered system for preheating while still plugged in.
• BMW i3 has an optional heat pump on the all-electric model.
• Chevrolet Bolt uses a resistance heating system – a heat pump option is not available. The base LT trim has an optional “Comfort and Convenience” package that includes heated front seats and steering wheel. The Premier trim includes heated steering wheel, front and rear seats as standard.
• Hyundai Ioniq Electric includes a heat pump on the higher “Limited” trim level. The base SE model does not have one. Hyundai Kona does not currently offer a heat pump for USA models, although one does come as standard equipment in Canadian models.
• Jaguar I-Pace includes a heat pump as standard equipment. A cold weather package is also available with a heated windshield and steering wheel.
• Kia Niro EV includes a heat pump in the Cold Weather Package, which also includes a heated steering wheel and battery heater.
• Mini Cooper SE all-electric includes a heat pump as standard equipment on all models.
• Nissan LEAF comes in S, SV and SL trims and the more efficient “hybrid heater system” is not available on the S, is optional on the SV (included in the all-weather package), and only standard on the top-of-the line SL Plus.
• Subaru Crosstrek Hybrid plug-in hybrid includes a heat pump system according to the owner’s manual.
• Tesla Model Y is the only Tesla currently offered with a heat pump, although other models include systems that recover waste heat from electronics to improve the efficiency of heating systems.
• Toyota Prius Prime and RAV4 Prime plug-in hybrids come standard with heat pump systems.
• Volkswagen e-Golf includes a heat pump on the higher SEL trim level. The baseline trim SE model does not have one.
• Volvo all-electric models will likely include heat pumps. Existing PHEV models may not offer them. Dealers should have additional information on heating system options.

Models not included on this list are unlikely to offer heat pumps, but we recommend checking automaker resources to confirm.

Traction and Clearance

If you live in a snowbelt or regularly travel on rough roads, you may want to consider an EV model with higher ground clearance or all-wheel drive. You can filter Drive Electric Vermont’s vehicle comparison tool (https://www.driveelectricvt.com/why-go-electric/compare-vehicles) to show what’s currently available.

EV batteries are often placed along the underside of the vehicle. This extra weight helps keep your wheels on the road, especially if you have winter tires installed. Studies have shown winter tires are the single most important investment you can make for safe winter driving in any vehicle, and EVs are no exception. Winter tires tend to be less efficient than all-season or summer tires, but in most cases, they will not have a major impact on range.

Most EVs available today have front wheel drive, which is fine for most winter driving conditions in the northeast when accompanied by winter tires and modern traction control systems. A growing number of EVs have all-wheel drive (AWD), including models from Toyota, Tesla (“dual motor”), Mitsubishi, Subaru, Audi, BMW, Mini and Volvo all offer models with AWD. Many more options are due to arrive in the next few years.

A few EV models have rear wheel drive (RWD) systems, which may be less predictable in winter road conditions. Many owners have reported traction-control systems and winter tires make RWD acceptable in northeast conditions. We recommend researching specific models prior to a purchase to ensure they will work for your needs.

Aerodynamic body parts help EVs maximize their range, but they do sometimes include trim pieces which reduce the ground clearance of the vehicle. Some EV models have adjustable suspension systems that allow drivers to increase ride height at the press of a button. Another option is putting in a “lift kit” that boosts the standard suspension further off the ground. If you regularly drive in deep, snowy conditions you can inquire with your dealer or manufacturer as there may be other options to provide more clearance.

Charging in Winter

EVs can charge on Level 1 charging (plugging into a standard 120V home outlet), which typically takes overnight or longer to charge. Faster Level 2 (240V) charging is also available. Some EVs include DC fast charging capability which can provide an 80% charge in 30-60 minutes under normal conditions. All three types of charging may require more time in cold winter conditions, but this is especially true of DC fast charging.

If you have a garage or carport for your EV that will help keep the battery a bit warmer. Some EVs have battery heaters that turn on in the coldest temperatures (e.g. below 0° F) to prevent permanent battery damage, so it is often prudent to leave your EV plugged in overnight when polar air visits your neighborhood – especially if your vehicle is parked outside. Check with your EV dealer or owner’s manual for more information on whether this is a consideration for your vehicle.

If you have an all-electric vehicle, upgrading to a Level 2 charger will speed your charging and can also boost your ability to preheat while still plugged in to save range.

For DC fast charging in winter, some EVs may have preconditioning systems that warm up the battery when you approach a fast charging stop. For example, if you are on a trip including a stop at one of their Supercharger DC fast chargers, be sure to use the built-in vehicle navigation system as it will automatically precondition the battery prior to a Supercharging session.

Driving Tips

Fortunately, there are some things EV drivers can do to restore some of the range lost in colder winter conditions. Best practices include:

• Preheating – getting the vehicle cabin up to temperature while still plugged in means more energy is available for range. This can often be controlled with smartphone apps or key fobs and generally works best on higher powered Level 2 chargers. Preheating can also make it much easier to remove snow and ice from your vehicle before leaving home.
• Departure Time Scheduling – Many EV models will allow you to schedule a departure time that will finish a charging session just before you need to go. This is a great way to get the battery warmed up a bit from charging and, for some models, it will include preheating.
• Heated Surfaces – Using heated seats and steering wheels if your vehicle has these is usually much more efficient than operating the cabin heat, even if you have a heat pump installed. Some drivers will use a lap blanket or continue wearing jackets to avoid operating heat for longer distance travels.
• Tire Pressure – Cold temps increase the density of air, which commonly leads to lower tire pressures. You can find the recommended tire pressure on a sticker located on the driver’s door jamb. Check pressure and add air regularly to increase winter efficiency.
• Driving Speed – reducing travel speed is one of the most effective ways to boost range in any condition as air resistance increases significantly with speed. Slowing down 5-10 mph can provide an additional 10-20% or more of range, depending on the model and conditions.
• Eco-Driving – Some vehicles have “eco” or economy modes that reduce power to the motors and do other things to increase efficiency. Also, following basic eco-driving principles (accelerating slowly, braking slowly, letting off on the accelerator as you crest a hill, and anticipating stoplights and slowing down) will help maximize the use of regenerative braking systems that put energy back in the battery instead of wasting it with mechanical brakes. You should also remove any heavy objects, roof racks, snow and ice, etc. from the vehicle when possible to increase efficiency.

Most EV owners find these practices become second nature, and they enjoy running their EVs year-round. That said, if you are in a single-car household and don’t relish the thought of more planning for road trips in winter, you may be happier with a plug-in hybrid EV model that can run on gasoline when needed.

Automakers and battery designers are working on new battery chemistries that promise more range and less impacts from colder temperatures, so hopefully these issues will continue to diminish as these technologies are integrated into future EVs.

Additional Resources

https://www.energy.gov/eere/electricvehicles/maximizing-electric-cars-range-extreme-temperatures

https://www.greencarreports.com/news/1109449_driving-electric-cars-in-winter-tips-from-experienced-owner

https://www.fueleconomy.gov/feg/evtips.shtml

https://insideevs.com/features/381393/tesla-model-3-winter-tips/

https://www.tesla.com/support/winter-driving-tips

David Roberts is the Drive Electric Vermont coordinator. He has driven all-electric vehicles for the past 8 years and says if you have to drive, drive electric.