When the heat is on, EV driving distance drops.

As summer temperatures climb, the distance covered by your fully charged electric vehicle may drop. A recent AAA study found that the driving range of an electric vehicle can be nearly 33 percent lower in extreme heat.

“Motorists are accustomed to shifts in fuel economy triggered by consistent use of the air conditioner in gasoline-powered vehicles,” says Greg Brannon, Director of AAA’s Automotive Engineering and Industry Relations Department. “Electric vehicles experience similar variations.”

Electric motors provide smooth operation, strong acceleration and require less maintenance than internal combustion engines. These environmentally friendly vehicles have the added benefit of reducing dependence on imported oil because they use domestically produced energy. Motorists with short daily commutes find electric vehicles a cost-effective option.

AAA’s analysis.

To help motorists better understand the fluctuations in EV battery range, AAA conducted tests of battery performance in cold, moderate and hot climates. The study was conducted with a Nissan Leaf, Ford Focus Electric and Mitsubishi iMiEV.

All of the vehicles evaluated demonstrated reduced driving range in hot climates; the average EV battery range was 169 kilometres at 24°C, but dropped to 111 kilometres per full charge at 35°C.

Battery-saving tips.

Batteries perform best in comfortable, 24°C weather. They are sensitive to heat and experience a high rate of degradation once temperatures rise above 35°F. Warm temperatures also cause the vehicle to use more battery power to cool the cabin.

Here are a few tips to maximize the range of your EV in extreme weather.

• Store the vehicle in the garage or shade to lower its internal temperature.
• Cool the car while it’s plugged in to reduce the drain on the battery.
• Check tire pressure frequently. Properly inflated tires can improve mileage.
• Map – or app – charging stations locations so that you are prepared for recharging. AAA’s TripTik® Travel Planner highlights electric vehicle charging stations along your route.

“A swing in miles per gallon is not as critical for gas-powered vehicles as it may be for an electric vehicle with limited charging options,” says Brannon. “Drivers need detailed knowledge of their vehicle’s range in various climates to plan accordingly.”