Cold weather can cut an electric vehicle’s range by 20%, says What Car?

Cold weather had reduce an electric vehicle’s range by more than 20%, research by What Car? has found.

However, the magazine’s research also suggested an EV fitted with a heat pump significantly improves cold weather efficiency.

Steve Huntingford, editor of What Car?, said: “Range remains one of the key considerations for electric car buyers, but when deciding whether a particular model can go far enough on a charge to fit into your life, it’s important to bear in mind that batteries don’t work as well in cooler conditions.”

The magazine, together with its sister title Move Electric, put cars through a real-world winter range test and then compared the results with those for identically-specced models tested last summer.

In the winter range test, the Porsche Taycan 4S Performance Battery Plus managed 224 miles on a full charge. That’s a 20.1% drop on the 281 miles that the same model on the same-sized wheels achieved when What Car? tested it last summer.

Other models retested included the Ford Mustang Mach-E Extended Range RWD (which fell 18.0% short of its summer figure), the Skoda Enyaq iV 60 (15.7%) and the Fiat 500 42kWh (15.2%).

What Car? and Move Electric also found that if you specify your electric car with a heat pump, drivers were able to get significantly closer to the official WLTP range.

A heat pump reduces strain on the battery by drawing excess heat from the electric drivetrain, distributing it around the interior of the car through the air conditioning. 

Five models so equipped were tested, with these falling short of their official WLTP mileage figures by an average of 25.4%.

By comparison, five models that relied on a regular interior heater suffered an average deficit of 33.6%. 

 The tests were conducted on a closed vehicle proving ground, on a 15-mile route consisting of 2.6 miles of simulated stop-start urban traffic, four miles of steady 50mph driving and eight miles driving at a constant speed of 70mph, to simulate motorway journeys. 

In July last year, What Car? research found EVs fell short of their WLTP range by 14.8%.

Winter vs summer range test results

Ranges of cars with and without heat pumps

> Interested in comparing electric vehicle data? Check out our EV tool.

> Interested in ensuring the efficient use of EVs. Check out our dedicated editorial sections: Insight & policy | EV news | Charging & infrastructure | Costs & incentives | Benefit-in-kind | EV case studies | EV road tests

> EVs by range

> EVs by their efficiency

> Rapid charging EVs

> EVs by price: lowest to highest