Extreme Weather Reduces Electric Car Range

Ever since electric cars were first introduced to the market, range anxiety has been one of their biggest problems. That's one of the reasons why they haven't caught on the way, on top of the high purchase price and long recharging times. In particular, electric car batteries have a reputation of not being able to perform at their best at low temperatures. There have been many reports of electric cars losing range in cold weather, with the most notable examples involving arguably the best all-electric car on the market, the Tesla Model S, which has been having issues when temperatures drop below freezing. Tesla, and other electric car manufacturers obviously claim that electric vehicles' performances are not affected by cold weather, but a recent research conducted by the AAA shows that range of electric cars does fluctuate in freezing weather.

What's more, the AAA says that battery range of EVs is not only affected by freezing temperatures, but by extremely hot weather, as well. The AAA Automotive Research Center in Southern California has tested the batteries of three electric cars: the 2013 Nissan Leaf, the 2014 Ford Focus, and the 2012 Mitsubishi iMIEV, and has found that their range drops up to 57% on average, depending on the temperature.

The range of these three vehicles was tested at cold, moderate, and hot temperatures. The AAA conducted simulations that replicated city driving, with stop-and-go traffic. The batteries of all vehicles were fully charged before the beginning of the tests, driving on a dynamometer in a climate-controlled room until their batteries were drained. When driving at 75 degrees Fahrenheit, which is a moderate temperature, the average range for a full charge was 105 miles. When the temperature dropped to 20 degrees, the average range was cut to 43 miles, which is a 57% decline. The difference wasn't that drastic in very hot weather, but still, when tested at 95 degrees, the average range was reduced to 69 miles, or 33% lower than at moderate temperatures. The tests were performed between December 2013 and January 2014.

Greg Brannon, AAA's director of automotive engineering, said that the Ford Focus and the Mitsubishi iMIEV had special devices that managed the battery temperature. He said: "We were expecting that difference would yield differences in the optimal range of the vehicles in extreme temperatures,", but it turned out that it did not. Brannon added that this huge fluctuations are probably due to the fact that in very cold or very hot weather, a significant amount of an electric car's battery is being used to heat or cool the battery, which leaves less power for the car's range.

AAA says that the goal of this research was not to highlight the drawbacks of electric vehicles. Actually, Brannon said that even with these reductions in range when driving at extreme temperatures, electric car batteries can still deliver a range that is enough for a round-trip commute, which is usually less than 40 miles.