What is an FFV?
An FFV, as its name implies, has the ex-
ibility of running on more than one type
of fuel. FFVs can be fueled with unleaded
gasoline, E85, or any combination of the
two. Like conventional gasoline vehicles,
FFVs have a single fuel tank, fuel system,
and engine. And they are available in a
wide range of models such as sedans,
pickups, and minivans. Light-duty FFVs
are designed to operate with at least 15%
gasoline in the fuel, mainly to ensure they
start in cold weather.
FFVs are equipped with modied
components designed specically to
be compatible with ethanol’s chemical
properties. In the illustration on the back,
the main modications for FFVs are
described. These modications ensure
seamless operation and a long useful life
across a wide range of ethanol blends.
Clean Cities posts a list of alternative fuel
vehicles, including FFVs, on its Alternative
Fuels and Advanced Vehicles Data Center
(AFDC) Web site at www.afdc.energy.gov.
To nd out about available models, go to
the Vehicles section of the AFDC and use
the Light-Duty Vehicle Search.
Can existing vehicles be
converted to FFVs?
Converting a conventional gasoline
vehicle to one that runs on E85 is techni-
cally possible. FFV conversions need to
be done by authorized companies and
require certication by the U.S. Environ-
mental Protection Agency (EPA) or the
California Air Resources Board. Using
noncertied conversions is illegal and
may affect warranties.
For more information on the vehicle
conversion process, refer to the EPA’s
Updated Certication Guidance for
Alternative Fuel Converters on its Web
site at www.epa.gov/otaq/cert/dearmfr/
cisd0602.pdf.
Does E85 aect vehicle
performance?
FFVs operating on E85 generally handle
and perform just as well as when fueled
with gasoline. Sensors in the FFV system
automatically prompt adjustments for fuel
composition, so emissions and standard
performance areas such as power and
acceleration are not signicantly affected
by E85. One difference between E85
and gasoline, however, is fuel economy.
Ethanol contains less energy per gal-
lon, which translates into a reduction in
fuel economy compared to gasoline. No
matter what type of fuel is used, however,
fuel mileage is affected by driving habits,
weather, and other factors.
Standard test results for fuel economy of
FFVs and their gasoline counterparts are
posted on the combined EPA and
U.S. Department of Energy Web site at
www.fueleconomy.gov.
What are the costs and
benefits of using E85?
Special features enabling vehicles to run
on E85 can add a minimal cost to their
purchase price. Because they have a
solid performance history, manufactur-
ers provide standard warranties for FFVs
equal to those for gasoline vehicles at no
additional charge.
Fuel, however, may be a cost factor.
E85’s reduced energy content compared
to gasoline, as explained in the previous
section, can increase fuel costs. This cost
differential is highly variable because it
is based on ethanol and gasoline price
differences. Like gasoline, ethanol prices
uctuate and are set based on market sup-
ply and demand. This variability means
that a driver may or may not experience
a difference in overall fuel costs, depend-
ing on local pump prices. To compare the
price of fueling with E85 versus gasoline,
use the AFDC’s Flexible Fuel Vehicle
Cost Calculator at www.afdc.energy.gov/
afdc/progs/cost_anal.php?0/E85.
Flexible Fuel Vehicles: Providing a Renewable
Fuel Choice
© GM Corp.
Flexible fuel vehicles can be fueled with
unleaded gasoline, E85, or any combination
of the two.
Today, almost 8 million vehicles on U.S. highways are flexible fuel
vehicles (FFVs). These vehicles can operate on gasoline or blends
of gasoline and ethanol up to E85 (85% ethanol, 15% gasoline).
As a renewable fuel, ethanol oers significant advantages. It is
manufactured predominantly in the United States, made from
homegrown feedstocks, and is cleaner burning than gasoline.
VEHICLE TECHNOLOGIES PROGRAM
www.cleancities.energy.gov • March 2010
Resources
AlternativeFuelsandAdvanced
VehiclesDataCenter
www.afdc.energy.gov
AmericanCoalitionforEthanol
wwwethanolorg
CleanCities
wwwcleancitiesenergygov
FuelEconomywwwfueleconomygov
GrowthEnergywwwefuelcom
HandbookforHandlingStoring
andDispensingE
wwwafdcenergygovafdcethanol
publicationshtml
RenewableFuelsAssociation
wwwethanolrfaorg
USEnvironmentalProtectionAgency
wwwepagovotaqconsumerfuels
altfuelsaltfuelshtm
VEHICLE TECHNOLOGIES PROGRAM
• March 2010 • Page 2
CLEAN CITIES
Where are E85 stations
located?
Stations offering E85 continue to increase
across the nation. As of January 2010,
more than 1,900 stations in 44 states sold
E85. To nd E85 stations throughout the
country, check out the Alternative Fuel
Station Locator at www.afdc.energy.gov/
stations, a database maintained by the
AFDC. This easy-to-use database allows
users to plot routes either across town or
across the nation, showing E85 stations
along the way.
1
Wang, Michael. Ethanol: The Complete Energy
Lifecycle Picture, Argonne National Laboratory,
March 2007.
2
Whitney, Kevin (Southwest Research Institute);
Fernandez, Tony (U. S. Environmental Protection
Agency). “Characterization of Cold Temperature
VOC and PM Emissions from Flex Fuel Vehicles
Operating on Ethanol Blends.” Presented at the
17th CRC On-Road Vehicle Emissions Workshop,
March 26–28, 2007.
Although your FFV’s fuel economy on
E85 is somewhat less than when operating
on gasoline, a bonus for its use is lower
greenhouse gas emissions. Using the
GREET model, Argonne National Labora-
tory indicates in “Ethanol, The Complete
Energy Lifecycle Picture” that greenhouse
gas emissions are reduced approximately
15% when ethanol produced from corn is
used.
1
Using E85 also reduces CO
2
emis-
sions and provides signicant reductions
in emissions of many harmful toxics,
including benzene, a known human
carcinogen. However, E85 also increases
emissions of acetaldehyde—a toxic pollut-
ant.
2
Additional testing is being completed
to expand the understanding of the emis-
sions impacts of E85.
How are FFVs identified?
Since September 2006, the Energy Policy
Act of 2005 requires auto manufacturers
to place a label inside the FFV fuel com-
partment that states the vehicle can run
on either E85 or gasoline. Flexible-fuel
capability also is outlined in the owner’s
manual and encoded in the vehicle identi-
cation number, or VIN.
EERE Information Center
1-877-EERE-INF (1-877-337-3463)
www.eere.energy.gov/informationcenter
Printed with a renewable-source ink on paper
containing at least 50% wastepaper, including
10% post consumer waste.
DOE/GO-102010-3002 • March 2010
Prepared by the National Renewable Energy Laboratory
(NREL), a national laboratory of the U.S. Department of
Energy, Oce of Energy Eciency and Renewable Energy;
NREL is operated by the Alliance for Sustainable Energy, LLC.
Fuel filler assembly:
Anti-siphon and spark
arrestor features are
included to handle
ethanol’s increased
conductivity.
Fuel rail and fuel lines: Must be made of
ethanol-compatible materials with seals, gaskets,
and rubber fuel hoses rated for ethanol use.
Fuel tank: Must be made
of ethanol-compatible
materials and designed to
minimize evaporative
emissions from ethanol.
Fuel system electrical connections and wiring:
System must be electrically isolated and made of
materials designed to handle ethanol’s increased
conductivity and corrosiveness (if exposed to fuel).
Internal engine parts: Piston
rings, valve seats, valves, and
other components must be
made of ethanol-compatible
materials that are designed to
minimize the cleansing eects
of alcohol fuels, which can
wash lubrication from parts.
Fuel identifier system:
System automatically
senses the composition
of the fuel and adjusts
engine for varying
ethanol-gasoline blends.
Fuel injection system: Must be made of ethanol-
compatible materials and designed for higher flow
to compensate for ethanol’s lower energy density.
Fuel pump assembly: In-tank components
must be made from ethanol-compatible
materials and sized to handle the
increased fuel flow needed to compen-
sate for ethanol’s lower energy density.
Engine calibration updates:
Fueling and spark advance calibrations
are directed by vehicle computer to
control combustion, enable cold start,
and meet emissions requirements.
Flexible Fuel Vehicle Features
