With Winter Comes Poor Gas Mileage

Have you been thinking that your car’s fuel economy has been lower over the last few weeks? If you have, it’s not your imagination it’s just the fact that, in winter, your fuel economy usually does go down, at least a little bit and in some cases quite a lot.

In fact, some cars can lose as much as a third of their fuel economy when the outside temperatures drops to 20°F, according to new research from the Oak Ridge National Laboratory. Not only that but on short trips during cold weather your fuel economy drops even further.

Bo Saulsbury, from Oak Ridge’s research group, said that “cold weather and winter driving conditions can reduce your fuel economy significantly,” adding that “fuel economy tests show that, in short-trip city driving, a conventional car’s gas mileage is about 12% lower.”

Oak Ridge compared to the fuel economy of over 600 conventional vehicles as well as 14 hybrids during weather that was 20° and compared that to their fuel economy during “normal” weather.

Interestingly enough, battery-based vehicles saw the biggest drop in fuel mileage, from between 31% and 34%. So, for example, a car that’s getting 45 MPG regularly will drop to only 30 mpg when the temperature outside  drops way down. Gas powered cars fared a little better but still didn’t do that well. For example, a car that normally gets 30 mpg will, when the temperature is 20°F or lower, drop down to 24 mpg during short trips.

The temperature alone isn’t the only reason that an automobile will be getting reduced fuel economy. Some other factors include;

• Roads that are icy or snow-covered, something that can decrease traction and waste fuel as a car literally spins its wheels
• Driving slower on ice, snow or slush covered roads. Most cars deliver their best mileage at higher speeds
• Operating a vehicle for long periods of time in four wheel or all-wheel drive
• Fluids like oil that have lower viscosity in the cold, increasing friction and the time it takes for a vehicle to reach optimal operating temperatures
• Power blower fans, seat heaters and defrosters using more energy
• Lower energy level gasoline blends made for the Winter
• Warming a vehicle up for an inordinate amount of time

One of the biggest problems that battery and gas powered vehicles have is the battery. When it’s cold a car’s battery is less efficient and thus requires that the alternator run more frequently. In a hybrid vehicle, cold batteries hold less energy and thus limit range and energy efficiency.

There are a number of things that drivers can do to improve their mileage, according to Oak Ridge. These include parking the car where it will stay warmer, combining trips and using an oil recommended for winter driving. Limiting the amount of time that your vehicle warms up is also a good idea, especially when you consider the fact that it will heat up faster while you’re actually driving it.

Then of course there’s the old standby, tire pressure. As the temperature falls, your tires aren’t as energy-efficient and if they are already low on air they become even less efficient because they don’t get an adequate grip on the road.

Hopefully these tips will help you to increase your mileage but, frankly, if you’re really worried about increasing your mpg during the winter it might be just a matter of getting up and moving to a warmer state like Florida, Texas or Southern California. If not, be careful and be safe while driving this Winter.