All gasoline vehicles are capable of operating on gasoline/ethanol blends with up to 10% ethanol. In fact, some states require the seasonal or year-round use of up to 10% ethanol as an oxygenate additive to gasoline to mitigate ozone formation. These low percentage oxygenate blends are not classified as alternative fuels. We speak of ethanol vehicles as those specifically manufactured to be capable of running on up to 85% denatured ethanol, 15% gasoline (E85), or any mixture of the two up to the 85% ethanol limit. E85 may be seasonally adjusted in colder climates such that the real proportion of E85 is less than 85% ethanol. Vehicles manufactured for E85 use are commonly called flexible fuel vehicles (FFVs). For more information on lower percentage ethanol blends, please see our site on fuel blends. For more information on alternative fuel vehicles capable of fueling with higher percentages of ethanol, read on.
Light-duty FFVs include a wide range of vehicles, from compacts to sport utility vehicles to pickup trucks. Unlike bi-fuel natural gas and propane vehicles that have two unique fueling systems, FFVs have only one fueling system. To qualify as an alternative fuel vehicle (AFV) for tax credits, incentives to meet requirements for mandated fleets (federal, state, and fuel provider fleets) under the Energy Policy Act of 1992 (EPAct), a vehicle must be capable of using fuel blends up to 85% ethanol.