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Ethanol, E85, Flex Fuel…What Does It All Mean?

Do You Drive an FFV?
Have you ever seen a truck that runs on E85?
Have you ever seen a truck that runs on E85?

How do you tell if you have a Flex Fuel Vehicle? A yellow gas cap may be your first clue, or some designation inside the fuel filler door displaying the E85 alphanumeric. Vehicles running on E85 tend to experience a drop in fuel economy versus gasoline (up to 25-30%) due to Ethanol’s lower energy content but at the benefit of burning cleaner. Vehicles burning the E10 fuel blend will see a drop of about 3-4% in fuel economy over straight gasoline.

As Ethanol can be produced by fermenting and distilling any starch crop or “cellulosic biomass,” it is a promising renewable fuel source that, at least for now, will help reduce the world’s petroleum dependence.

One obstacle that stands in Ethanol’s way now is the higher fuel economy standards imposed by the current U.S. administration. As E85 is less efficient, automakers will be putting their efforts into ways to quickly increase the numbers the EPA places on those window stickers and Ethanol-rich fuel is not one of those – for now.