The E85 blend is used in gasoline engines modified to accept
such higher concentrations of ethanol, and the fuel injection is regulated
through a dedicated sensor, which automatically detects the amount of ethanol
in the fuel, allowing to adjust both fuel injection and spark timing
accordingly to the actual blend available in the vehicle's tank. Because
ethanol contains close to 34% less energy per unit volume than gasoline, E85
FFVs have a lower mileage per gallon than gasoline. Based on EPA tests for all 2006
E85 models, the average fuel economy for E85 vehicles was 25.56% lower than
unleaded gasoline.
The American E85 flex-fuel vehicle was
developed to run on any mixture of unleaded gasoline and ethanol, anywhere from
0% to 85% ethanol by volume. Both fuels are mixed in the same tank, and E85 is
sold already blended. In order to reduce ethanol evaporative emissions and to
avoid problems starting the engine during cold weather, the maximum blend of
ethanol was set to 85%. There is also a seasonal reduction of the ethanol
content to E70 (called winter E85 blend) in very cold regions, where
temperatures fall below 0 °C (32 °F) during the winter. In Wyoming
for example, E70 is sold as E85 from October to May.
E85 flex-fuel vehicles are becoming increasingly
common in the Midwest, where corn is a major crop and is the primary feedstock
for ethanol fuel production. Regional retail E85 prices vary widely across the
US, with more favorable prices in the Midwest region, where most corn is grown
and ethanol produced. Depending of the vehicle capabilities, the break-even
price of E85 has to be between 25 and 30% lower than gasoline.
As ethanol
FFVs became commercially available during the late 1990s, the common use of the
term "flexible-fuel vehicle" became synonymous with ethanol FFVs. In
the United States flex-fuel vehicles are also known as "E85
vehicles". In Brazil, the FFVs are popularly known as "total
flex" or simply "flex" cars. In Europe, FFVs are also known as
"flexifuel" vehicles. Automakers, particularly in Brazil and the
European market, use badging in their FFV models with the some variant of the
word "flex", such as Volvo Flexifuel, or Volkswagen Total
Flex, or Chevrolet FlexPower or Renault Hi-Flex, and Ford
sells its Focus model in Europe as Flexifuel and as Flex in
Brazil. In the US, only since 2008 FFV models feature a yellow gas cap with the
label "E85/Gasoline" written on the top of the cap to differentiate
E85s from gasoline only models.
Flexible-fuel vehicles (FFVs) are based on
dual-fuel systems that supply both fuels into the combustion chamber at the
same time in various calibrated proportions. The most common fuels used by FFVs
today are unleaded gasoline and ethanol fuel. Ethanol FFVs can run on pure
gasoline, pure ethanol (E100) or any combination of both. Methanol has also
been blended with gasoline in flex-fuel vehicles known as M85 FFVs, but their
use has been limited mainly to demonstration projects and small government
fleets, particularly in California.
The term flexible-fuel vehicle is sometimes
used to include other alternative fuel vehicles that can run with compressed
natural gas (CNG), liquefied petroleum gas (LPG; also known as autogas), or hydrogen.
However, all these vehicles actually are bi-fuel and not flexible-fuel vehicles,
because they have engines that store the other fuel in a separate tank, and the
engine runs on one fuel at a time. Bi-fuel vehicles have the capability to
switch back and forth from gasoline to the other fuel, manually or
automatically. The most common available fuel in the market for bi-fuel cars is
natural gas (CNG), and by 2008 there were 9,6 million natural gas vehicles, led
by Pakistan (2.0 million), Argentina (1.7 million), and Brazil (1.6 million).
Natural gas vehicles are a popular choice as taxicabs in the main cities of
Argentina and Brazil. Normally, standard gasoline vehicles are retrofitted in
specialized shops, which involve installing the gas cylinder in the trunk and
the CNG injection system and electronics.
Multifuel vehicles are capable of
operating with more than two fuels. In 2004 GM do Brasil introduced the Chevrolet
Astra 2.0 with a "MultiPower" engine built on flex fuel technology
developed by Bosch of Brazil, and capable of using CNG, ethanol and gasoline
(E20-E25 blend) as fuel. This automobile was aimed at the taxicab market and
the switch among fuels is done manually. In 2006 Fiat introduced the Fiat Siena
Tetra fuel, a four-fuel car developed under Magneti Marelli of Fiat Brazil.
This automobile can run as a flex-fuel on 100% ethanol (E100); or on E-20 to
E25, Brazil's normal ethanol gasoline blend; on pure gasoline (though no longer
available in Brazil since 1993, it is still used in neighboring countries); or
just on natural gas. The Siena Tetrafuel was engineered to switch from any
gasoline-ethanol blend to CNG automatically, depending on the power required by
road conditions. Another existing option is to retrofit an ethanol
flexible-fuel vehicle to add a natural gas tank and the corresponding injection
system. This option is popular among taxicab owners in São Paulo and Rio de
Janeiro, Brazil, allowing users to choose among three fuels (E25, E100 and CNG)
according to current market prices at the pump. Vehicles with this adaptation
are known in Brazil as "tri-fuel" cars.
Flex-fuel hybrid electric and
flex-fuel plug-in hybrid are two types of hybrid vehicles built with a
combustion engine capable of running on gasoline, E-85, or E-100 to help drive
the wheels in conjunction with the electric engine or to recharge the battery
pack that powers the electric engine. In 2007 Ford produced 20 demonstration Escape
Hybrid E85s for real-world testing in fleets in the U.S. Also as a
demonstration project, Ford delivered in 2008 the first flexible-fuel plug-in
hybrid SUV to the U.S. Department of Energy (DOE), a Ford Escape Plug-in Hybrid,
which runs on gasoline or E85. GM announced that the Chevrolet Volt plug-in
hybrid, launched in the U.S. in late 2010, would be the first commercially
available flex-fuel plug-in capable of adapting the propulsion to several world
markets such as the U.S., Brazil or Sweden, as the combustion engine can be
adapted to run on E85, E100 or diesel respectively. The Volt was initially
expected to be flex-fuel-capable in 2013.]
Lotus Engineering unveiled the Lotus CityCar at the 2010 Paris Motor Show. The
CityCar is a plug-in hybrid concept car designed for flex-fuel operation on ethanol,
or methanol as well as regular gasoline.
A 2005 survey found that 68 percent
of American flex-fuel car owners were not aware they owned an E85 flex. This
was because the exteriors of flex and non-flex vehicles look exactly the same;
there is no sale price difference between them; the lack of consumers'
awareness about E85s; and also the initial decision of American automakers of
not putting any kind of exterior labeling, so buyers could be aware they are
purchasing an E85 vehicle. Since 2008, all new FFV models in the US feature a bright
yellow gas cap to remind drivers of the E85 capabilities and proper flex-fuel
badging.
Some critics have argued that
American automakers have been producing E85 flex models motivated by a loophole
in the Corporate Average Fuel Economy (CAFE) requirements, that allows for a
fuel economy credit for every flex-fuel vehicle sold, whether or not in
practice these vehicles are fueled with E85. This loophole might allow the car
industry to meet the CAFE targets in fuel economy just by spending between US$100
and US$200 that it cost to turn a conventional vehicle into a flex-fuel,
without investing in new technology to improve fuel economy, and saving them
the potential fines for not achieving that standard in a given model year. The
CAFE standards proposed in 2011 for the period 2017-2025 will allow
flexible-fuel vehicles to receive extra credit but only when the carmakers
present data proving how much E85 such vehicles have actually consumed.
A major restriction hampering sales
of E85 flex vehicles, or fueling with E85, is the limited infrastructure
available to sell E85 to the public. As of May 2011, there were only 2,749
gasoline fueling stations selling E85 to the public in the entire US, with a
great concentration of E85 stations in the Corn Belt states. The main
constraint for a more rapid expansion of E85 availability is that it requires
dedicated storage tanks at filling stations, at an estimated cost of US$60,000
for each dedicated ethanol tank. The Obama Administration set the goal of
installing 10,000 blender pumps nationwide until 2015, and to support this
target the US Department of Agriculture (USDA) issued a rule in May 2011 to
include flexible fuel pumps in the Rural Energy for America Program (REAP).
This ruling will provide financial assistance to fuel station owners to install
E85 and blender pumps.
General Motors announced that the
new Chevrolet Volt plug-in hybrid, launched in the United States market in
December 2010, will be flex-fuel-capable in 2013. General Motors do Brasil
announced that it will import from five to ten Volts to Brazil during the first
semester of 2011 as part of a demonstration and also to lobby the federal
government to enact financial incentives for green cars. If successful, GM
would adapt the Volt to operate on ethanol fuel, as most new cars sold in
Brazil are flex-fuel.
In 2008, Chrysler, General Motors, and Ford
pledged to manufacture 50 percent of their entire vehicle line as flexible fuel
in model year 2012, if enough fueling infrastructure develops. The Open Fuel
Standard Act (OFS), introduced to Congress in May 2011, is intended to promote
a massive adoption of flex-fuel vehicles capable of running on ethanol or
methanol. The bill requires that 50 percent of automobiles made in 2014, 80
percent in 2016, and 95 percent in 2017, would be manufactured and warranted to
operate on non-petroleum-based fuels, which includes existing technologies such
as flex-fuel, natural gas, hydrogen, biodiesel, plug-in electric and fuel cell.
|
Comparison of key
characteristics among the leading
ethanol flexible-fuel vehicle markets |
||||
|
Characteristic
|
Units/comments
|
|||
|
80% imported
|
||||
|
23.0 million
|
229,400
|
10 million(1)
|
||
|
Share of flex-fuel vehicles as % of total
registered
|
22.0%
|
4.7%
|
4.0%
|
|
|
35,017
|
1,723
|
2,757
|
Brazil for December
2007, the US and Sweden as of August 2011.
|
|
|
100%
|
30%
|
1.7%
|
As % of total
fueling gas stations in the country.
|
|
|
Ethanol fueling stations per million inhabitants
|
184.2
|
130.4
|
6.5
|
See List of countries by population.
Brazil and US as of 2008-09-12, and Sweden as of 2008-06-30.
|
|
US$ 2.60/gal
|
||||
|
Retail price of gasoline or E25. (local currency/unit)
|
US$ 3.70/gal
|
|||
|
Price economy ethanol/gasoline price as %
|
47.2%(2)(3)
|
26.7%(3)
|
29.7%(2)(3)
|
São Paulo, June 2008,
Sweden January 2008, and Minnesota, August 2008.
|
|
Notes: (1)The
effective number of E85 flex vehicles in US roads actually using ethanol fuel
is lower than shown, as a survey have shown than 68% of E85 owners are not
aware they own a flex-fuel vehicle.[12]
A 2007 national survey found that only 5% of drivers actually use biofuels.[189]
(2) Regional prices vary widely in Brazil and the US. The states chosen
reflect some of the lowest retail prices for ethanol, as both São Paulo and Minnesota
are main growers of feedstock and producers of ethanol, hence, the comparison
presented is one of the most favorable for ethanol/gasoline price ratios. For
example, US average spread was 16.9% in August 2008, and it varied from 35%
in Indiana
to 3% in Utah.[188]
See more US price comparisons for most states at e85prices.com, and annual fuel costs for
2008 FFV US models at www.fueleconomy.gov.
(3) Brazilian gasoline is heavily taxed (~54%),[190]
US ethanol production was subsidized (a US$ 0.51/gal federal tax credit)
until December 2011,[95]
and Swedish E85 is exempt of CO2 and energy taxes until 2009 (~30% price
reduction).[109][124]
|
||||
Certain information for this article was
sourced from Wikipedia.org
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