Winter Weather Cuts MPGs by One Third: Study

Luke Vandezande
by Luke Vandezande

It shouldn’t come as much of a surprise that colder weather hurts fuel economy, but you might be surprised to learn how steep the penalties can be.

Results from new research conducted by Oak Ridge National Laboratory suggests that some vehicles suffer a third hit in mpgs in 20-degree weather. The returns worsen in colder weather and during short trips where the car has less time to warm up.

Conventional gasoline vehicles suffered a roughly 12 percent drop at that temperature compared to “normal” conditions, but cars like the Ford Fusion Hybrid exhibited declines between 31 and 34 percent.

Cold weather is a major contributing factor to decreased mileage, but there are other reasons for cars returning worse fuel economy. Tires slipping on snow and ice will cause them to spin, using more fuel. People tend to let their cars idle longer in cold weather where they get zero miles per gallon and the car’s systems operate less efficiently in cold weather. For example, running seat heaters and fans calls for more energy from the car. Winter fuel blends are also less energy dense. In colder temperatures, your vehilce’s fluids will also cause more internal friction.

But Oak Ridge suggests a handful of steps to improve your winter fuel economy. They suggest using the manufacturer-recommended oil for cold weather use. Spend less time running your car at idle to warm it up. It will reach the optimal operating temperature sooner while driving. It’s also important to be diligent about tire pressure. Tires lose pressure in cold weather and softer tires cause rolling resistance and cost more fuel.

Luke Vandezande
Luke Vandezande

Luke is an energetic automotive journalist who spends his time covering industry news and crawling the internet for the latest breaking story. When he isn't in the office, Luke can be found obsessively browsing used car listings, drinking scotch at his favorite bar and dreaming of what to drive next, though the list grows a lot faster than his bank account. He's always on <A title="@lukevandezande on Twitter" href="">Twitter</A> looking for a good car conversation. Find Luke on <A title="@lukevandezande on Twitter" href="">Twitter</A> and <A title="Luke on Google+" href="">Google+</A>.

More by Luke Vandezande

Join the conversation
 1 comment
  • Danwat1234 Danwat1234 on Feb 11, 2014

    It especially hurts MPG when you find a nice big open parking lot by your house and help yourself to some power slides and donuts every day until the snow melts!