Flex Fuel

What is Flex Fuel?

 Flex fuel is a phrase many people use when talking about a flex fuel vehicles. Flex fuel is short for flexible fuel, and it's used to describe vehicles with an internal combustion engine which runs on more than one type of fuel. Flex fuel vehicles usually operate on a blend of gasoline and either ethanol or methanol. Both the gasoline and the ethanol or methanol are kept in the same storage tank. Flex-fuel vehicles, or FFVs, can burn any proportion of this combination. Electronic sensors control the operation of the timing and spark plugs to accomodate the blend being used. Flex-fuel vehicles, which can use either gasoline or an ethanol blend up to 85 percent (E85).

Flex-fuel vehicles are not the same thing as hybrids, which generally run on a combination of gasoline and battery power. They are also not the same thing as electric cars, which run solely on battery-powered electricity.

Brazil and the United States lead the world in FFV use. According to recent statistics, Brazil has more than million automobiles, motorcycles and light duty trucks, and the U.S. has about 9 million. Canada and Sweden are two other countries where FFV use is becoming more common.

There as also been some testing done in the U.S. and Europe with methanol-gasoline blends. Vehicles that use the methanol blend are known as M85 vehicles. In Europe, M85 and E85 FFVs are generally called flexifuel vehicles.

The blend is set at a maximum of 85 percent ethanol in the U.S. due to ethanol emissions at low temperatures and to avoid cold starting problems during cold weather. In some areas of the world, including Wyoming in the United States, ethanol content is reduced to 70 percent during the winter months.

Auto manufacturers have been producing FFV’s since the 1980’s, although the history of FFvs goes all the way back to Henry Ford's first Model T in 1908. But fuels using ethanol fell out of favor during the Prohibition years in the United States and didn't start making a comeback until the oil supply crisis of the 70s. Many popular cars today are FFV’s. There’s a good chance your own car is an FFV. To find out, check your owner’s manual or look for a sticker on the inside of your fuel tank hatch.

If your car is an FFV and you have not run E85 in it before, you may wonder how your car will perform. Running an FFV on ethanol will not affect performance at all; your car will run as it always has. However, a gallon of ethanol does contain less energy than a gallon of gasoline, so you should expect a mileage reduction of 20-30 percent.

If you have an FFV vehicle, or are considering buying one, using E85 whenever possible is a great way to drive a conventional vehicle, use renewable fuel without an expensive conversion, and have an impact on the environment, all at the same time.

Also see our articles on green vehicles, alternative fuels and how to get better gas mileage.