If you live in a state hit by this winter's extreme weather, you already know how miserable it is to drive on snow and ice. But to makes things worse, the cold weather is likely cutting your car's gas mileage and boosting your bill for gasoline.
When the temperature is at 20 degrees, conventional gas engines get 12 percent lower gas mileage on short trips than in warm weather of 77 degrees, according to a study done at the Oak Ridge National Laboratory. With hybrids, mileage can be cut by over 30 percent. These results came from applying different temperatures to the EPA test procedure that measures estimated MPG for the government web site fueleconomy.gov.
The cold weather affects your mileage partly because cold engine oil and other fluids increase friction in the engine. And it takes longer for the engine to reach its most fuel efficient temperature, which especially cuts the mileage on short trips. In hybrids, the cold weather affects battery performance, meaning that you need to use the auxiliary gasoline engine more often.
But you can minimize this drain on gas and your wallet by taking some simple steps to help increase your gas mileage. Here are five mileage-boosting habits recommended by the scientists at Oak Ridge National Lab:
- If you have a garage, keep the car inside so that the engine will remain warmer than if it sat outside.
- Don't warm up your car at an idle, when you are getting zero MPG. Instead, drive off gently about 30 seconds after starting the engine, which will warm up faster while being driven.
- If you have errands to do, combine trips so that you will be driving less with a cold engine.
- Don't use seat warmers or defrosters more than necessary, since they additionally cut gas mileage.
- Check your tire pressure frequently. Cold weather decreases tire pressure, which in turn hurts gas mileage. This is a safety issue as well, since underinflated tires have a harder time gripping slick surfaces.
This cold winter is probably boosting your home heating bill. At least by taking some preventive action you can keep your gasoline costs from soaring as well.