As gasoline prices at the pump hit record highs, some drivers are wondering about cheaper ways to fill their cars.

One of those options, at least for some drivers, is ecofriendly E85 fuel. E85 is a fuel that contains gasoline, but also consists of up to about 85% ethanol, a renewable resource which is made from plant materials such as corn, sugar cane, and grasses. The percentage of ethanol depends on the geographical location and time of the year.

Here is how to check if can you put E85 in your car, as well as some factors you might want to consider.

Which vehicles use E85?

E85 should only be put in certain vehicles, called flex fuel vehicles (FFVs), which have a fuel delivery system and engine that are designed to use it. Many drivers already own a FFV and do not even know it!  To check if a car is a flex fuel vehicle, see U.S. Department of Energy’s (DOE) fuel economy site or simply look for a few signs:

  • Yellow-colored gas cap, yellow ring around capless fuel fillers, or a flex fuel label on the fuel door
  • Markers on the outside of the car with the labels: E85, FFV or Flex Fuel
  • Reference to E85 in the owner’s manual

FFVs are capable of running on both ethanol-gasoline blends like E85 and regular gasoline. However, it is NOT recommended to put E85 fuel in any vehicle other than a flex fuel vehicle. Doing so can ruin the engine and void the manufacturer’s warranty.

In addition to needing to be used in a flex fuel vehicle, E85 is not as widely available in some parts of the United States.  There are over 3,900 E85 stations throughout the country, and the DOE’s AFDC fuel locator, offered both in a mobile app and web version, can help drivers find the closest E85 stations. 

What are the benefits of E85?

  • E85 generates more torque and horsepower than gasoline
  • E85 burns cleaner and leaves no residue
  • E85's105 octane rating and cooling properties combine to provide a higher resistance to engine knocking than gasoline
  • E85 has fewer emissions than gasoline, resulting in cleaner air
  • By using less petroleum, we stretch our domestic supply of oil further, resulting in less dependence on foreign oil

How much does E85 cost?

As of June 10, the national average for E85 fuel was $4.316 per gallon.  That is 67 cents less or 22% lower than the average national price for regular gasoline, which was a record high of $4.986 per gallon, according to AAA.  This price difference offers a more-affordable fuel option for flex fuel vehicle owners.  However, like gasoline prices, alternative fuel prices can vary based on location, time of year, geopolitical events, and fluctuations of the energy markets.

While E85 is typically cheaper per gallon than gasoline it might be more expensive per mile. Since ethanol contains less energy per volume than gasoline, FFVs will generally get 15%-27% fewer miles per gallon when fueled with E85, depending on the car and the driver’s driving habits. Consumers can use the DOE’s vehicle cost calculator to determine how much a flex-fuel vehicle can save on fuel costs and greenhouse gas emissions.

For more information on FFVs and E85 check out Energy Saver’s Consumer Guide to Ethanol and Flexible Fuel Vehicles.