Category: Community

by Paul Cutting, Energy Planner

Electric Vehicles (EVs) have improved by leaps and bounds over the past five years. The 2017 Nissan Leaf—then one of only a few EVs on the market—had a range of just 107 miles. Today that same vehicle has a range of 215 miles. In fact, most new entry level EVs, like the Chevy Bolt (259 miles range), the upcoming Chevy Equinox (300 miles), the upcoming Blazer (300 miles), VW’s ID.4 (275 miles) and the Kia Niro (253 miles) all have ranges approaching their equivalent internal combustion engine counterparts. In fact, the number of 2022 models with ranges of at least 300 miles grew to fourteen as compared to five from the year before. But beyond improvements in range and ever-increasing access and availability to public charging infrastructure, there are several other lesser known considerations one should take into account when contemplating an EV, including cold weather range reduction, vehicle charging speed, how the vehicle is heated, and whether the vehicle will be stored in a heated garage. 

All EVs exhibit reduced performance in cold weather. If you’re a current hybrid driver, you know what I’m talking about. My small hybrid truck consistently gets 45-48 mpg during the warm months, but struggles to achieve 32 mpg during the winter. Battery performance, and the systems meant to protect batteries from freezing during cold weather, greatly affect winter mileage. This is true whether you’re driving a hybrid, plug-in hybrid, or pure EV. Some EVs have reported cold weather performance losses of 30% of rated range. EPA range calculations are complex, but the short end of it is that they don’t accurately account for real-world winter driving conditions. 

Some EVs suffer more range loss during cold weather driving than others, and much of this variation is due to how the vehicle’s cabin is heated. A normal internal combustion engine vehicle siphons heat from the engine and uses this byproduct to heat the vehicle. That advantage doesn’t exist for a vehicle without a gas engine, and instead heating is achieved through either an electric resistance element or the combination of a heat pump coupled with an auxiliary electric resistance element. 

The combination heat pump/electric resistance heater uses less electricity than a sole resistance element, and as a result has less effect on cold weather performance. For example, the Ford Mustang Mach-E with its resistance heater suffers a roughly 30% cold weather range hit, whereas the Tesla 3 with its hybrid heat pump/resistance heater suffers a range hit about half that. When comparing heating systems between EVs, keep in mind that not all trim levels of the same model use the same method of cabin heating. Some entry level trims may utilize resistance heating while the seemingly same higher end trims may utilize a hybrid system.

A related consideration is how the vehicle is stored, or whether the vehicle can be preheated while still connected to electrical supply. An EV stored in a heated garage will have a much lessened cold weather range and performance hit. Before going any further, I’m not implying that having a heated garage is a requirement of EV ownership in our climate, or that anyone should heat their garage for the sole purpose of making their EV happy in the winter. That said, an EV stored well above freezing with its battery and cabin preheated close to room temperature will operate much better than one stored outside in freezing temperatures. Similarly, some models have features that allow for either scheduled or keyfob activated preheating while the vehicle is connected to external power. 

EV ownership will become more compelling for more people as public charging becomes widely available. EV charging is done at three speeds: Level 1, 2 and 3. Level 1 charging utilizes a standard wall outlet operating at 120 volts and achieves a rate of charge of about 2-4 miles of range per hour, depending on vehicle efficiency. Level 2 charging utilizes 240 volt power, and is what’s most widely available at public chargers. Level 2 charging achieves a rate of charge anywhere from 18 to 50 miles of range per hour and is really the only option for public charging currently available in Northeast Iowa. 

Level 2 charging speeds vary greatly by vehicle. For example, the Nissan Leaf is capable of charging at a rate of about 23 miles per hour of charge while the Chevy Bolt can achieve a rate of about 44 miles per hour. Keep in mind, level 2 charging speed varies depending on both the capability of the vehicle and the capability of the charger (or outlet) the vehicle is plugged into. Most EV owners charge at home at level 1 or 2, and with adequate time spent charging overnight, consideration of level 2 charging speeds, in practice, really doesn’t matter all that much. With level 3 DC fast charging still scarce for the foreseeable future, level 2 charging speeds become important for those who need a charge to get home.

Some day relatively soon, level 3 charging will be available at commercial locations in Northeast Iowa. Some slow level 3 chargers allow for a rate of charge of about 75 miles per hour, whereas the fastest level 3 chargers (350 kW in speed), can fully charge (from about 10% capacity to 80% capacity) in as short as 15 minutes.  (Lithium-based batteries are not designed to be fully discharged or charged, and instead operate in that sweet spot between 10-80% of charge.) But not all vehicles can accept 350kW level 3 charging, and some only allow for level 3 charging speeds of up to 50kW. For example, the Chevy Bolt can be charged from 10% to 80% capacity in about an hour (at a rate of 50kW), whereas higher-end EVs like the Hyundai Ioniq 5 can charge in as short as 18 minutes (at a rate of 350kW).

As Level 3 charging rolls out more widely throughout the country, especially along interstate corridors, which was prioritized in the Bipartisan Infrastructure Law, a level 3 rate of charge will become increasingly important. The challenges for  those taking their EVs on road trips cross countryare widely documented.

If you’re in the market for a new vehicle or are EV-curious, now might be the time to take the plunge. Ranges of EVs have increased tremendously over the last few years, more entry level models with fantastic ranges are coming to market every year, and the nationwide network of Level 3 DC fast chargers is currently being built. Despite the fact that some changes in the EV tax credit that will make some models ineligible (see our prior newsletter post here), many vehicles still qualify for the $7,500 credit, which in some cases puts EVs at cost parity to their gas equivalents.