What Are Flexible-Fuel Vehicles?

Definition and Examples of Flexible-Fuel Vehicles


Flexible-fuel vehicles, or FFVs, are cars that can run on gasoline or a gasoline-ethanol blend containing up to 85% ethanol.

Woman at the gas station refueling car
Photo: Jecapix / Getty Images

What Are Flexible-Fuel Vehicles?

FFVs are cars, SUVs, or trucks with the option to run on gasoline or a gasoline-ethanol blend containing up to 85% ethanol. Common gasoline-ethanol blends include E85, E15, and E10, where the number after the "E" signifies the maximum percentage of ethanol in the fuel.

Although ethanol has a lower energy content than regular gasoline, such vehicles typically don't exhibit performance loss other than a decline of 15% to 27% of their fuel efficiency when E85 is used.

  • Acronym: FFVs
  • Alternate name: Flex-fuel vehicles


Despite the "E85" moniker, the U.S. Department of Energy technically defines this flexible fuel as a gasoline-ethanol blend containing between 51% and 83% ethanol.

How Flexible-Fuel Vehicles Work

Henry Ford built the first FFV, the 1908 Model-T Ford, which could run on either gasoline or ethanol. But it wasn't until 1994 that the first mass-produced FFV hit the market. The Ford Taurus E85 was released that year with the ability to run on gasoline or gasoline blended with ethanol (a renewable grain alcohol made from corn or sugarcane). It also had a computer system that could distinguish between fuel blends to optimize the car's performance.

Today, there are many more options for FFVs on the market today. According to the Renewable Fuels Association, there were more than 24 million FFVs on the road in the United States as of 2018.

FFVs have the same acceleration, payload, power, and cruise speed as traditional gasoline-powered cars and trucks, and require similar maintenance. They even look the same. In fact, short of looking up the fuel type of a car in the owner's manual, the only qualities that might visibly distinguish an FFV from a regular car are:

  • A yellow gas cap or fuel-filler ring
  • A label of "E85" on the fuel door
  • Badges on the body of the vehicle, such as "E85," "Flex-Fuel," or "FFV"

The main difference is that the fuel systems and other components of FFVs are uniquely designed to handle a blend of gasoline and ethanol ranging from 0% to 85%. While this design enables gasoline to be used when E85 isn't available, the lower energy content of ethanol means that you'll get 15% to 27% fewer miles per gallon with a flexible fuel than with gasoline, which only contains about 10% ethanol. That said, you'll typically experience no substantial loss in performance; in fact, some FFVs offer greater torque and horsepower when they run on E85 than on gasoline.


Driving a flexible-fuel vehicle will cause your gas mileage performance to decline somewhat, but this drawback is partially offset by the generally lower per-gallon costs of a gasoline-ethanol blend.

Pros and Cons of Flexible-Fuel Vehicles

These vehicles have their advantages and drawbacks:

  • Choice of fuel

  • Cleaner fumes

  • Less dependence on imported energy sources

  • Lower fuel economy

  • Limited availability of E85

  • Not eligible for a tax credit

Pros Explained

The advantages of flexible-fuel vehicles include:

  • Choice of fuel: As the name implies, an FFV empowers you to choose between using traditional gasoline and a gasoline-ethanol blend. If, for example, E85 prices are lower than gasoline in your area, you could save money. And when the blend is unavailable, you can fuel up with gas.
  • Cleaner fumes: While FFVs still emit waste from the tailpipe, ethanol is a renewable fuel that burns cleaner than traditional gasoline does, reducing greenhouse gas emissions and keeping the air around you cleaner.
  • Less dependence on imported energy sources: E85 also fuel helps achieve the goal of reducing our reliance on foreign oil while supporting the domestic economy by improving the condition of local farmers who grow the corn and sugarcane used to produce ethanol.

Cons Explained

The negatives of flexible-fuel vehicles include:

  • Lower fuel economy: Ethanol is a less-efficient source of fuel than traditional gasoline is; in other words, ethanol-laden fuel contains less usable energy for an equal amount of gas. Because of this, a flex-fuel vehicle running on a blended fuel like E85 is going to have a slightly lower gas mileage. Depending on E85 prices, you might have to pay more to travel a shorter distance when you opt for this fuel type.
  • Limited availability of E85: E85 is sold at more than 2,500 stations in the U.S., but it may not be offered at your local pump. If that's the case, you'll have an FFV but won't be able to take advantage of its environmental and fuel cost benefits.
  • Not eligible for a tax credit: Currently, the Internal Revenue Service only offers a tax credit for consumers on qualified plug-in electric vehicles.

How Much Do Flexible-Fuel Vehicles Cost?

An FFV doesn’t necessarily cost more than any other type of vehicle. The U.S. Department of Energy offers a list of the various FFVs on the market. Among 2020 models are the Chevrolet Impala, Ford Explorer, and GMC Yukon. While costs may differ by dealership and location, Kelly Blue Book might put the MSRP of these new vehicles at $32,495, $34,010, and $50,895, respectively.

That said, the costs of driving your car will also depend on your choice of fuel, as well as car maintenance costs. Your location can have an impact on fuel cost, as can the state of the global oil market and the yield of corn and sugarcane crops in recent years. E85 is typically cheaper per gallon than regular gasoline but more expensive per mile. E85 costs an average of $2.74 per gallon in the U.S. as of November 2021, compared to $3.68 for regular gasoline (E0).


Compare fuel costs and determine fuel savings for FFVs at FuelEconomy.gov.

Do the math and figure out whether it makes sense for your budget to fuel with E85. For example, if you estimate that you lose 25% of your fuel efficiency on E85, and regular gasoline is $2.50 a gallon at the station, consider fueling your car with E85 only if's priced at $1.88 per gallon or less.

Lastly, choosing to drive a flexible-fuel vehicle will not necessarily increase or decrease your car insurance premium. Of course, the type of vehicle itself might: A sporty model is going to be more costly to insure in general, whether fueled by traditional gas or a gasoline-ethanol blend.

Key Takeaways

  • A flexible-fuel vehicle can run on gasoline or a gasoline-ethanol blend containing up to 85% ethanol.
  • It performs as gasoline-powered cars do and may be visibly distinguishable from one only by its gas cap color or FFV-affiliated labels or badges on the vehicle.
  • It offers an eco-friendly alternative to a traditional gasoline-only vehicle that can save on fuel costs per gallon but can slightly reduce fuel economy.
  • You should factor in the cost of the vehicle, fuel, and maintenance to determine if an FFV fits into your budget.
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The Balance uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. FuelEconomy.gov. "Flex-Fuel Vehicles." Accessed Nov. 25, 2021.

  2. U.S. Department of Energy. "Fact Sheet: Ford Taurus: Ethanol-Fueled Vehicle." Accessed Nov. 25, 2021.

  3. Renewable Fuels Association. "RFA Releases Updated Brochure Allowing Consumers To Track Latest Flex Fuel Models." Accessed Nov. 25, 2021.

  4. National Service Center for Environmental Publications (NSCEP). "E85 and Flex Fuel Vehicles." Accessed Nov. 25, 2021.

  5. U.S. Department of Energy. "Ethanol." Accessed Nov. 25, 2021.

  6. Internal Revenue Service. "Plug-In Electric Vehicle Credit IRC 30 and IRC 30D." Accessed Nov. 25, 2021.

  7. FuelEconomy.gov. "New Flex-fuel Vehicles." Accessed Nov. 25, 2021.

  8. E85Prices. "E85 Prices." Accessed Nov. 25, 2021.

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