Fuel Ethanol: Background and Public Policy Issues

Fuel Ethanol:
Background and Public Policy Issues
Updated April 24, 2008
Brent D. Yacobucci
Specialist in Energy and Environmental Policy
Resources, Science, and Industry Division

Fuel Ethanol: Background and Public Policy Issues
Ethanol plays a key role in policy discussions about energy, agriculture, taxes,
and the environment. In the United States it is mostly made from corn; in other
countries it is often made from cane sugar. Fuel ethanol is generally blended in
gasoline to reduce emissions, increase octane, and extend gasoline stocks. Recent
high oil and gasoline prices have led to increased interest in alternatives to petroleum
fuels for transportation. Further, concerns over climate change have raised interest
in developing fuels with lower fuel-cycle greenhouse-gas emissions. Supporters of
ethanol argue that its use can lead to lower emissions of toxic and ozone-forming
pollutants, and greenhouse gases, especially if higher-level blends are used. They
further argue that ethanol use displaces petroleum imports, thus promoting energy
security. Ethanol’s detractors argue that various federal and state policies supporting
ethanol distort the market and amount to corporate welfare for corn growers and
ethanol producers. Further, they argue that the energy and chemical inputs needed
to turn corn into ethanol actually increase emissions and energy consumption,
although most recent studies have found modest energy and emissions benefits from
ethanol use relative to gasoline, depending on how the ethanol is produced.
The market for fuel ethanol is heavily dependent on federal incentives and
regulations. Ethanol production is encouraged by a federal tax credit of 51 cents per
gallon. This incentive allows ethanol — which has historically been more expensive
than conventional gasoline — to compete with gasoline and other blending
components. In addition to the above tax credit, small ethanol producers qualify for
an additional production credit. It has been argued that the fuel ethanol industry
could scarcely survive without these incentives.
In addition to the above tax incentives, the Energy Policy Act of 2005 (P.L. 109-
58) established a renewable fuel standard (RFS). This RFS was expanded by the
Energy Independence and Security Act of 2007 (P.L. 110-140), and requires the use
of 9.0 billion gallons of renewable fuels in 2008, increasing each year to 36 billion
gallons in 2022. Much of this requirement will likely be met with ethanol. In
addition, the bill requires that an increasing share of the mandate be met with
“advanced biofuels” — biofuels produced from feedstocks other than corn starch.
Potential “advanced biofuels” include domestic ethanol from cellulosic material
(such as perennial grasses and municipal solid waste), ethanol from sugar cane, and
diesel fuel substitutes produced from a variety of feedstocks. The United States
consumed approximately 6.8 billion gallons of ethanol in 2007, mostly from corn.
A sigificant supply of cellulosic ethanol is likely several years off. Some analysts
believe the RFS could have serious effects on motor fuel suppliers, leading to higher
fuel prices.
Other issues of congressional interest include support for purer blends of ethanol
as an alternative to gasoline (as opposed to a gasoline blending component),
promotion of ethanol vehicles and infrastructure, and imports of ethanol from foreign
countries. This report supersedes CRS Report RL30369, Fuel Ethanol: Background
and Public Policy Issues, by Brent D. Yacobucci and Jasper Womach (out of print
but available from the authors).

In troduction ......................................................1
Ethanol Basics....................................................1
Ethanol and the Agricultural Economy.................................2
Ethanol Refining and Production......................................3
Fuel Consumption.................................................6
E85 Consumption.............................................7
Development of Cellulosic Feedstocks.................................9
Economic Effects.................................................11
Air Quality......................................................13
Before the Energy Policy Act of 2005.........................13
Following the Energy Policy Act of 2005......................14
E85 and Air Quality.......................................15
Energy Consumption and Greenhouse Gas Emissions....................15
Energy Balance..........................................15
Greenhouse Gas Emissions.................................16
Policy Concerns and Congressional Activity............................18
Renewable Fuel Standard (RFS).................................18
“Boutique” Fuels.............................................20
Alcohol Fuel Tax Incentives....................................21
Ethanol Imports..............................................21
Fuel Economy Credits for Dual Fuel Vehicles......................22
The 2008 Farm Bill...........................................23
Conclusion ......................................................23
List of Tables
Table 1. Corn Utilization, 2007-2008 Forecast..........................3
Table 2. Top 10 Ethanol Producers by Capacity, March 2008...............4
Table 3. Estimated U.S. Consumption of Fuel Ethanol, Gasoline,
and Diesel....................................................8
Table 4. Wholesale Price of Pure Ethanol Relative to Gasoline.............12
Table 5. Expanded Renewable Fuel Standard Requirements
Under P.L. 110-140...........................................19

Fuel Ethanol:
Background and Public Policy Issues
The promotion of alternatives to petroleum, including fuel ethanol, has been an
ongoing goal of U.S. energy policy. This promotion has led to the establishment of
significant federal policies beneficial to the ethanol industry, including tax incentives,
import tariffs, and mandates for ethanol use. The costs and benefits of ethanol —
and the policies that support it — have been questioned. Areas of concern include
whether ethanol yields more or less energy than the fossil fuel inputs needed to
produce it; whether ethanol decreases reliance on petroleum in the transportation
sector; whether its use increases or decreases greenhouse gas emissions; and whether
various federal policies should be maintained.
This report provides background and discussion of policy issues relating to U.S.
ethanol production, especially ethanol made from corn. It discusses U.S. fuel ethanol
consumption both as a gasoline blending component and as an alternative to gasoline.
The report discusses various costs and benefits of ethanol, including fuel costs,
pollutant emissions, and energy consumption. It also outlines key areas of
congressional debate on policies beneficial to the ethanol industry.
Ethanol Basics
Fuel ethanol (ethyl alcohol) is made by fermenting and distilling simple sugars.
It is the same compound found in alcoholic beverages. The biggest use of fuel
ethanol in the United States is as an additive in gasoline. It serves as an oxygenate,
to prevent air pollution from carbon monoxide and ozone; as an octane booster, to
prevent early ignition, or “engine knock”; and as an extender of gasoline stocks. In
purer forms, it can also be used as an alternative to gasoline in automobiles specially
designed for its use. It is produced and consumed mostly in the Midwest, where corn
— the main feedstock for domestic ethanol production — is grown.
The initial stimulus for ethanol production in the mid-1970s was the drive to
develop alternative and renewable supplies of energy in response to the oil
embargoes of 1973 and 1979. Since the 1970s, production of fuel ethanol has been
encouraged through federal tax incentives for ethanol-blended gasoline. The use of
fuel ethanol was further stimulated by the Clean Air Act Amendments of 1990,
which required the use of oxygenated or reformulated gasoline (RFG). The Energy
Policy Act of 2005 (P.L. 109-58) established a renewable fuels standard (RFS),
which mandates the use of ethanol and other transportation renewable fuels.

Approximately 99% of fuel ethanol consumed in the United States is “gasohol”1 or
“E10” (blends of gasoline with up to 10% ethanol). About 1% is consumed as “E85”
(85% ethanol and 15% gasoline), and alternative to gasoline.2
Fuel ethanol is usually produced in the United States from the distillation of
fermented simple sugars (e.g., glucose) derived primarily from corn, but also from
wheat, potatoes, or other vegetables.3 However, ethanol can also be produced from
cellulosic material such as switchgrass, rice straw, and sugar cane waste (known as
bagasse). The alcohol in fuel ethanol is identical chemically to ethanol used for other
purposes such as distilled spirit beverages and industrial products.4
Ethanol and the Agricultural Economy5
Corn constitutes about 95% of the feedstock for ethanol production in the
United States. The other 5% is largely grain sorghum, along with some barley,
wheat, cheese whey and potatoes. Corn is used because it is a relatively low cost
source of starch that can be relatively easily converted to simple sugars, and then
fermented and distilled. The U.S. Department of Agriculture (USDA) estimates that
about 3.2 billion bushels of corn will be used to produce about 6 billion gallons of
fuel ethanol during the 2007/2008 corn marketing year (September 2007 through6
August 2008). This is roughly 25% of the projected 13 billion bushels of total corn
utilization for all purposes.7 However, it should be noted that ethanol production
capacity is expanding rapidly, and corn demand for ethanol production may exceed
USDA’s projection.8
In the absence of the ethanol market, lower corn prices probably would
stimulate increased corn utilization in other markets, but sales revenue would not be
as high. The lower prices and sales revenue would likely result in higher federal
spending on corn subsidy payments to farmers, as long as corn prices were to stay
below the price triggering federal loan deficiency subsidies.

1 Technically, gasohol is any blend of ethanol and gasoline, but the term most often refers
to the 10% blend.
2 U.S. Department of Energy (DOE), Energy Information Administration (EIA), Alternatives
to Traditional Transportation Fuels 2005, updated November 2007.
3 In some other countries, most notably Brazil, ethanol is produced from cane sugar.
4 Industrial uses include perfumes, aftershaves, and cleansers.
5 For a more detailed discussion of ethanol’s role in agriculture, see CRS Report RL32712,
Agriculture-Based Renewable Energy Production, by Randy Schnepf.
6 One bushel of corn generates approximately 2.7 gallons of ethanol.
7 Utilization data are used, rather than production, due to the existence of carryover stocks.
Corn utilization data address the total amount of corn used within a given period.
8 As of March 2008, the Renewable Fuels Association reported U.S. production capacity at
8.3 billion gallons, with an additional 5.1 billion gallons of capacity under construction
(including expansions of existing plants). See [http://www.ethanolrfa.org/industry/
locations/] (updated March 17, 2008).

Table 1. Corn Utilization, 2007-2008 Forecast
(million bushels)Share of total use
Livestock feed & residual5,95045.9%
Food, seed & industrial:4,55535.2%
— Fuel alcohol3,20024.7%
— High fructose corn syrup5003.9%
— Glucose & dextrose2351.8%
— Starch2702.1%
— Cereals & other products1931.5%
— Beverage alcohol1351.0%
— Seed220.2%
Exports 2,450 18.9%
Total Use12,955100.0%
Total Production13,074
Source: Basic data are from USDA, Economic Research Service, Feed Outlook, March 13, 2008.
Note: Annual use can exceed production through the use of stocks carried over from previous years.
Ethanol Refining and Production
According to the Renewable Fuels Association,9 about 80% of the corn used for
ethanol is processed by “dry” milling plants (which use a grinding process) and the
other 20% is processed by “wet” milling plants (which use a chemical extraction
process). The basic steps of both processes are similar. First, the corn is processed,
with various enzymes added to separate fermentable sugars from other components
such as protein and fiber; some of these other components are used to make
coproducts, such as animal feed. Next, yeast is added to the mixture for fermentation
to make alcohol. The alcohol is then distilled to fuel-grade ethanol that is 85%-95%
pure. Then the ethanol is partially dehydrated to remove excess water. Finally, for
fuel and industrial purposes the ethanol is denatured with a small amount of a
displeasing or noxious chemical to make it unfit for human consumption.10 In the
United States, the denaturant for fuel ethanol is gasoline.
Ethanol is produced largely in the Midwest corn belt, with roughly 70% of the
national output occurring in five states: Iowa, Nebraska, Illinois, Minnesota and
South Dakota. Because it is generally less expensive to produce ethanol close to the

9 [http://www.ethanolrfa.org/].
10 Renewable Fuels Association, Ethanol Industry Outlook 2002, Growing Homeland
Energy Security.

feedstock supply, it is not surprising that the top corn-producing states in the U.S. are
also the main ethanol producers. This geographic concentration is an obstacle to the
use of ethanol on the East and West Coasts. Most ethanol use is in the metropolitan
centers of the Midwest, where it is produced. When ethanol is used in other regions,
shipping costs tend to be high, since ethanol-blended gasoline cannot travel through
petroleum pipelines, but must be transported by truck, rail, or barge. However, due
to Clean Air Act requirements,11 concerns over other fuel additives, and the
establishment of a renewable fuels standard, ethanol use on the East and West Coasts
is growing steadily. For example, in 1999 California and New York accounted for

5% of U.S. ethanol consumption, increasing to 22% in 2003, and 33% in 2004.12

The potential for expanding production geographically is one motivation behind
research on cellulosic ethanol. If regions could locate production facilities closer to
the point of consumption, the costs of using ethanol could be lessened. Furthermore,
if regions could produce fuel ethanol from local crops, there could be an increase in
regional agricultural income.
Table 2. Top 10 Ethanol Producers by Capacity, March 2008
(existing production capacity — million gallons per year)
Archer Daniels Midland (ADM)1,070
VeraSun Energy Corporation560
U.S. BioEnergy Corp.420
Hawkeye Renewables225
Aventine Renewable Energy207
Abenoga Bioenergy Corp.198
White Energy148
Renew Energy130
All others4,024
Source: Renewable Fuels Association, U.S. Fuel Ethanol Industry Plants and Production Capacity,
March 17, 2008.

11 P.L. 109-58 amended the Clean Air Act to eliminate the reformulated gasoline oxygenate
standard, one of the key federal policies promoting the use of ethanol. However, the act also
established a renewable fuels standard, effectively mandating the use of ethanol. (See
“Renewable Fuels Standard” below.)
12 U.S. Department of Transportation, Federal Highway Administration, Highway Statistics
Series, 1999, 2003, and 2004.

Historically, ethanol production was concentrated among a few large producers.
However, that concentration has declined over the past several years. Table 2 shows
that currently, the top five companies account for approximately 42% of production
capacity, and the top ten companies account for approximately 48% of production
capacity. Critics of the ethanol industry in general — and specifically of the ethanol
tax incentives — have argued that the tax incentives for ethanol production equate13
to “corporate welfare” for a few large producers. However, the share of production
capacity controlled by the largest producers has been dropping as more producers
have entered the market.
Section 1501(a)(2) of the Energy Policy Act of 2005 required the Federal Trade
Commission (FTC) to study whether there is sufficient competition in the U.S.
ethanol industry. The FTC concluded that “the level of concentration in ethanol
production would not justify a presumption that a single firm, or a small group of
firms, could wield sufficient market power to set prices or coordinate on prices or
output.”14 Further, they concluded that the level of concentration has been decreasing
in recent years.
Overall, at the beginning of 2008, domestic ethanol production capacity was
approximately 8 billion gallons per year, and is expected to grow to 13 billion gallons15
per year, counting existing plants and plants under construction. Under various
federal and state laws and incentives, consumption has increased from 1.8 billion
gallons per year in 2001 to 6.8 billion gallons per year in 2007. Domestic production
capacity will continue increasing to meet the growing demand, including increased
demand resulting from implementation of the renewable fuels standard established
by the Energy Policy Act of 2005.
Fuel is not the only output of an ethanol facility, however. Coproducts play an
important role in the profitability of a plant. In addition to the primary ethanol
output, the corn wet milling process generates corn gluten feed, corn gluten meal, and
corn oil, and dry milling process creates distillers grains. Corn oil is used as a
vegetable oil and is priced higher than soybean oil; the other coproducts are used as
livestock feed. In 2004, U.S. ethanol mills produced 7.3 million metric tons of
distillers grains, 2.4 million metric tons of corn gluten feed, 0.4 million metric tons16
of corn gluten meal, and 560 million pounds of corn oil.
Revenue from the ethanol byproducts help offset the cost of corn used in ethanol
production. The net cost of corn relative to the price of ethanol and the difference
between ethanol and wholesale gasoline prices are the major economic determinants

13 Erin M. Hymel, The Heritage Foundation, Ethanol Producers Get a Handout from
Consumers, October 16, 2002.
14 Federal Trade Commission, 2006 Report on Ethanol Market Concentration, December

1, 2006. p. 2.

15 Renewable Fuels Association, U.S. Fuel Ethanol Industry Plants and Production
Capacity, March 2008.
16 Renewable Fuels Association, Ethanol Industry Outlook 2005, Homegrown for the
Homeland, February 2005.

of the level of ethanol production. Higher the corn prices lead to lower profits for
ethanol producers; higher gasoline prices lead to higher profits. Recently, high corn
prices have cut into corn ethanol producers’ profits.
Fuel Consumption
Approximately 7 billion gallons of ethanol fuel were consumed in the United
States in 2007, mainly blended into E10 gasohol (a blend of 10% ethanol and 90%
gasoline). This figure represents only 5% of the approximately 140 billion gallons
of gasoline consumption in the same year.17 Under the renewable fuels standard,
motor fuel will be required to contain 36 billion gallons of renewable fuel annually
by 2022. It is expected that much of this requirement will be met with ethanol.
Ethanol consumption in 2007 accounted for approximately 4% of combined18
gasoline and diesel fuel consumption. Because of its physical properties, ethanol
can be more easily substituted for — or blended into — gasoline, which powers most
passenger cars and light trucks. However, heavy-duty vehicles are generally diesel-
fueled. For this reason, research is ongoing into ethanol-diesel blends.
A key barrier to wider use of fuel ethanol is its cost relative to gasoline. Even
with tax incentives for ethanol use (see the section on Economic Effects), the fuel is
often more expensive than gasoline per gallon.19 Further, since fuel ethanol has a
somewhat lower energy content per gallon, more fuel is required to travel the same
distance. This energy loss leads to a 2%-3% decrease in miles-per-gallon vehicle fuel
economy with 10% gasohol. This is due to the fact that there is simply less energy
in one gallon of ethanol than in one gallon of gasoline, as opposed to any detrimental20
effect on the efficiency of the engine.
However, ethanol’s chemical properties make it very useful for some
applications, especially as an additive in gasoline. The oxygenate requirement of the
Clean Air Act Reformulated Gasoline (RFG) program provided a major boost to the
use of ethanol.21 Oxygenates are used to promote more complete combustion of
gasoline, which reduces carbon monoxide (CO) emissions and may reduce volatile
organic compound (VOC) emissions.22 In addition, oxygenates can replace other
chemicals in gasoline, such as benzene, a toxic air pollutant. Conversely, the higher

17 DOE, EIA, Alternatives to Traditional Transportation Fuels 2005, Table C1.
18 Ibid.
19 However, gasoline prices have been high recently, making ethanol more attractive as a
blending component.
20 In fact, there is some evidence that the combustion efficiency of an engine improves with
the use of ethanol relative to gasoline. In this way, a greater percentage of energy in the fuel
is transferred to the wheels. However, this improved efficiency does not completely negate
the fact that there is less energy in a gallon of ethanol than in a gallon of gasoline.
21 Section 211, Subsection k; 42 U.S.C. 7545.
22 CO, VOCs and nitrogen oxides are the main precursors to ground-level ozone.

volatility of ethanol-blended gasoline can in some cases lead to higher VOC
emissions (see “Air Quality,” below).
The two most common oxygenates are ethanol and methyl tertiary butyl ether
(MTBE). Until recently, MTBE, made primarily from natural gas or petroleum
products, was preferred to ethanol in most regions because it was generally much less
expensive, easier to transport and distribute, and available in greater supply. Because
of different distribution systems and gasoline blending processes, substituting one
oxygenate for another can lead to significant transitional costs, in addition to the cost
differential between the two additives.
Despite the cost differential, there are several possible advantages of using
ethanol over MTBE. Since ethanol is produced from agricultural products, it has the
potential to be a sustainable fuel, while MTBE is produced from fossil fuels, either
natural gas or petroleum. In addition, ethanol is readily biodegradable, eliminating
some of the potential concerns about groundwater contamination that have
surrounded MTBE (see the section on MTBE). However, there is concern that
ethanol use can increase the risk of groundwater contamination by benzene and other
toxic compounds.23
Both ethanol and MTBE also can be blended into otherwise non-oxygenated
gasoline to raise the octane rating of the fuel. High-performance engines and older
engines often require higher octane fuel to prevent early ignition, or “engine knock.”
Other chemical additives may be used for the same purpose, but some of these
alternatives are highly toxic, and some are regulated as pollutants under the Clean Air
Act.24 Furthermore, since these other additives do not contain oxygen, their use may
not lead to the same emissions reductions as oxygenated gasoline.
E85 Consumption
In purer forms, such as E85, ethanol can also be used as an alternative to
gasoline in vehicles specifically designed to use it. Currently, this use represents only
approximately 1% of ethanol consumption in the United States. To promote the
development of E85 and other alternative fuels, Congress has enacted various
legislative requirements and incentives. The Energy Policy Act of 1992 requires the
federal government and state governments, along with businesses in the alternative

23 Gasoline contains many different chemical compounds, including toxic substances such
as benzene. In the case of a leaking gasoline storage tank, various compounds within the
gasoline, based on their physical properties, will travel different distances through the
ground. The concern with ethanol is that there is very limited evidence that plumes of
benzene and other toxic substances travel farther if ethanol is blended into gasoline.
However, this property has not been firmly established, as it has not been studied in depth.
Susan E. Powers, David Rice, Brendan Dooher, and Pedro J. J. Alvarez, “Will Ethanol-
Blended Gasoline Affect Groundwater Quality?,” Environmental Science and Technology,
January 1, 2001, p. 24A.
24 Lead was commonly used as an octane enhancer until it was phased-out through the mid-
1980s (lead in gasoline was completely banned in 1995), due to the fact that it disables
emissions control devices, and because it is toxic to humans.

fuel industry, to purchase alternative-fueled vehicles.25 In addition, under the Clean
Air Act Amendments of 1990, municipal fleets can use alternative fuel vehicles as
one way to mitigate air quality problems. Both E85 and E95 (95% ethanol with 5%
gasoline) are currently considered alternative fuels by the Department of Energy.26
The small amount of gasoline added to the alcohol helps prevent corrosion of engine
parts and aids ignition in cold weather.
Table 3. Estimated U.S. Consumption of
Fuel Ethanol, Gasoline, and Diesel
(million gasoline-equivalent gallons)
1996 1998 2000 2002 2004
E95 3 0 a 000
Ethanol in6608901,1101,1202,052b
Gasohol (E10)
Gasolinec 117,800 122,850 125,720 130,740 136,370
Diesel 30,100 33,670 36,990 38,310 40,740
Source: Department of Energy, Alternatives to Traditional Transportation Fuels 1999.
a. A major drop in E95 consumption occurred between 1997 and 1998 because the number of E95-
fueled vehicles in operation dropped from 347 to 14, due to the elimination of an ethanol-fueled
municipal bus fleet in California. This fleet was eliminated due to higher fuel and maintenance
costs. DOE currently reports that no E95 vehicles were in operation in 2004.
b. An estimated 3.4 billion gallons of ethanol were consumed in 2004. However, due to ethanol’s
lower energy content, the number of equivalent gallons is lower.
c. Gasoline consumption includes ethanol in gasohol.
Approximately 22 million gasoline-equivalent gallons (GEG)27 of E85 were
consumed in 2004, mostly in Midwestern states.28 (See Table 3.) A key reason for
the relatively low consumption of E85 is that there are relatively few vehicles that
operate on E85. In 2006 the National Ethanol Vehicle Coalition estimated that there29
were approximately six million E85-capable vehicles on U.S. roads, as compared

25 P.L. 102-486. For example, of the light-duty vehicles purchased by a federal agency in
a given year, 75% must be alternative fuel vehicles.
26 More diluted blends of ethanol, such as E10, are considered to be “extenders” of gasoline,
as opposed to alternatives.
27 Since different fuels produce different amounts of energy per gallon when consumed, the
unit of a gasoline-equivalent gallon (GEG) is used to compare total energy consumption.
It takes roughly 1.4 gallons of E85 to equal the energy content in one gallon of gasoline.
28 DOE, EIA, Alternatives to Traditional Transportation Fuels.
29 National Ethanol Vehicle Coalition, Frequently Asked Questions, accessed February 3,

2006 [http://www.e85fuel.com/e85101/faq.php].

to approximately 230 million gasoline- and diesel-fueled vehicles.30 Most E85-
capable vehicles are “flexible fuel vehicles” or FFVs. An FFV can operate on any
mixture of gasoline and 0% to 85% ethanol. A large majority of FFVs on U.S. roads
are fueled exclusively on gasoline. In 2004, approximately 146,000 flexible fuel
vehicles (FFVs) were actually fueled by E85.31 Proponents of E85 and FFVs argue
that even though few FFVs are operated on E85, the large number of these vehicles
already on the road means that incentives to expand E85 infrastructure are more
likely to be successful.
One obstacle to the use of alternative fuel vehicles is that they generally have
a higher purchase price than conventional vehicles, although this margin has
decreased in recent years with newer technology. Another obstacle is that, as stated
above, fuel ethanol is often more expensive than gasoline or diesel fuel. In addition,
there are very few fueling sites for E85, especially outside of the Midwest. As of
February 2006, there were 556 fuel stations with E85, as compared to roughly
120,000 gasoline stations across the country. Further, 362 (65%) of these stations
were located in the five highest ethanol-producing states: Minnesota, Illinois, Iowa,
South Dakota, and Nebraska. In February 2006, there were only 60 stations in 10
states along the east and west coasts, where population — and thus fuel demand —
is higher. However, E85 capacity is expanding rapidly, and the number of E85
stations nearly tripled (to 1,365) between February 2006 and March 2008, and the
number along the coasts had increased to 146 stations in 13 states (although roughly
half of all stations are still in the top five ethanol-producing states).
Development of Cellulosic Feedstocks
A key barrier to ethanol’s expanded role in U.S. fuel consumption is its price
differential with gasoline. Since a major part of the total production cost is the cost
of feedstock, reducing feedstock costs could lead to lower wholesale ethanol costs.
For this reason, there is a great deal of interest in producing ethanol from cellulosic
feedstocks. Cellulosic materials include low-value waste products such as recycled
paper and rice hulls, or dedicated fuel crops, such as switchgrass32 and fast-growing
trees. A dedicated fuel crop would be grown and harvested solely for the purpose of
fuel production.
However, as the name indicates, cellulosic feedstocks are high in cellulose.
Cellulose forms a majority of plant matter, but it is generally fibrous and cannot be

30 Federal Highway Administration, Highway Statistics 2003, November 2004.
31 DOE, EIA, Alternatives to Traditional Transportation Fuels. In 1997, some
manufacturers began making flexible E85/gasoline fueling capability standard on some
models. However, some owners may not be aware of their vehicles’ flexible fuel capability.
32 Switchgrass is a tall, fast-growing perennial grass native to the North American tallgrass
prairie. It is of key interest because it readily grows with limited fertilizer use in marginal
growing areas. Further, its cultivation can improve soil quality.

directly fermented.33 It must first be broken down into simpler molecules, which is
currently expensive. A 2000 study by USDA and the National Renewable Energy
Laboratory (NREL) estimated a 70% increase in production costs with large-scale
ethanol production from cellulosic biomass compared with ethanol produced from
corn.34 Therefore, federal research has focused on both reducing the process costs
for cellulosic ethanol and improving the availability of cellulosic feedstocks. The
Natural Resources Defense Council estimates that with mature technology, advanced
ethanol production facilities could produce significant amounts of fuel at $0.59 to
$0.91 per gallon (before taxes) by 2012, a price that is competitive with Energy
Information Administration (EIA) projections for gasoline prices in 2012.35
Other potential benefits from the development of cellulosic ethanol include
lower greenhouse gas and air pollutant emissions and a higher energy balance36 than
corn-based ethanol.37 Further, expanding the feedstocks for ethanol production could
allow areas outside of the Midwest to produce ethanol with local feedstocks.
In his 2006 State of the Union Address, President Bush announced an expansion
of biofuels research at the Department of Energy.38 A stated goal in the speech is to
make cellulosic ethanol “practical and competitive within six years,” with a potential
goal of reducing Middle East oil imports by 75% by 2025.39 This goal would require
an increase in ethanol consumption to as much as 60 billion gallons, from 4.9 billion
gallons in 2004.40 As part of the FY2007 DOE budget request, the Administration
sought an increase of 65% above FY2006 funding for “Biomass and Biorefinery
Systems R&D,” which includes research into cellulosic ethanol.41 In his 2007 State
of the Union Address, President Bush further defined a goal of increasing the use of

33 Lee R. Lynd, Dartmouth College, Cellulosic Ethanol Fact Sheet, June 13, 2003. For the
National Commission on Energy Policy Forum: The Future of Biomass and Transportation
34 Andrew McAloon, Frank Taylor, and Winnie Yee (USDA), and Kelly Ibsen and Robert
Wolley (NREL), Determining the Cost of Producing Ethanol from Corn Starch and
Lignocellulosic Feedstocks, October 2000.
35 Nathanael Greene, Natural Resources Defense Council, Growing Energy - How Biofuels
Can Help End America’s Oil Dependence, December 2004, Table 18.
36 The ratio of the energy needed to produce a fuel to that fuel’s energy output. For more
details, see section below on “Energy Balance.”
37 Alexander E. Farrell, Richard J. Plevin, Brian T. Turner, Andrew D. Jones, Michael
O’Hare, and Daniel M. Kammen, “Ethanol Can Contribute to Energy and Environmental
Goals,” Science, January 27, 2006, pp. 506-508.
38 President George W. Bush, State of the Union Address, January 31, 2006,
[ ht t p: / / www.whi t e house.gov/ news/ r el eases/ 2006/ 01/ 20060131-10.ht ml ] .
39 Ibid.
40 Peter Rhode, “Bush Biofuel Goal Likely Means Speeding Current Plans By Decades,”
New Fuels and Vehicles.com, February 3, 2006.
41 The FY2006 appropriation was $91 million; the FY2007 request is $150 million. DOE,
FY2007 Congressional Budget Request, February 2006, vol. 3, p. 141.

renewable and alternative fuels to 35 billion gallons by 2017.42 This would mean a
roughly seven-fold increase from 2006 levels. Such an increase would most likely
be infeasible using corn and other grains as feedstocks. Therefore, the President’s
goal will likely require significant breakthroughs in technology to convert cellulose
into motor fuels.
As stated above, the Energy Independence and Security Act of 2007 (P.L.110-
140) expanded the renewable fuel standard (RFS). Further, starting in 2016, and
increasing share of the RFS must come from “advanced biofuels,” such as cellulosic
ethanol, ethanol from sugar cane, and biodiesel. Further, of the advanced biofuel
mandate (which reaches 21 billion gallons in 2022), there is a specific carve-out for
cellulosic biofuels (reaching 16 billion gallons in 2022).
Economic Effects
Ethanol’s relatively high price is a major constraint on its use as an alternative
fuel and as a gasoline additive. As a result, ethanol has not been competitive with
gasoline except with incentives. Wholesale ethanol prices, excluding incentives from
the federal government and state governments, are significantly higher than
wholesale gasoline prices. With federal and state incentives, however, the effective
price of ethanol is reduced. Furthermore, gasoline prices have risen recently, making
ethanol more attractive as both a blending component and as an alternative fuel.
Before 2004, the primary federal incentive supporting the ethanol industry was
a 5.2 cents per gallon exemption that blenders of gasohol (E10) received from the
18.4¢ federal excise tax on motor fuels. Because the exemption applied to blended
fuel, of which ethanol comprises only 10%, the exemption provided for an effective
subsidy of 52 cents per gallon of pure ethanol. The 108th Congress replaced this
exemption with an income tax credit of 51 cents per gallon of pure ethanol used in
blending (P.L. 108-357).43 Table 4 shows that ethanol and gasoline prices are
competitive on a per gallon basis when the ethanol tax credit is factored in.
However, the energy content of a gallon of ethanol is about one third lower than a
gallon of gasoline. As Table 4 shows, on an equivalent energy basis, ethanol can be
significantly more expensive than gasoline, even with the tax credit.
The comparative cost figures in Table 4 are for ethanol as a blending
component in gasoline. However, the use of E85 in flexible fuel vehicles has been
associated with improved combustion efficiency. The National Ethanol Vehicle
Coalition estimates that FFVs run on E85 experience a 5% to15% decrease in miles-44
per-gallon fuel economy, as opposed to the 29% drop in Btu content per gallon.
Therefore, on a per-mile basis, E85’s cost premium is likely in the middle of these
above estimates.

42 President George W. Bush, State of the Union Address, January 23, 2007,
[ ht t p: / / www.whi t e house.gov/ news/ r el eases/ 2007/ 01/ 20070123-2.ht ml ] .
43 26 U.S.C. 40.
44 National Ethanol Vehicle Coalition, op. cit.

Table 4. Wholesale Price of Pure Ethanol Relative to Gasoline
(August 2006 to January 2008)
Relative price byRelative price on an
volumeequivalent energy basisc
Ethanol Wholesale Pricea150 to 250cents/gallon227 to 379cents/equivalent gallon
Alcohol Fuel Tax Incentive51 cents/gallon77 cents/equivalentgallon
Effective Price of Ethanol99 to 199cents/gallon150 to 302cents/equivalent gallon
Gasoline Wholesale Priceb135 to225cents/gallon135 to 225 cents/gallon
Wholesale Price Differenced(-)101 to (+)39cents/gallon(-)50 to (+)142cents/gallon
Source: CRS analysis of Chicago Board of Trade, Ethanol Derivatives, Updated through January
2008, February 13, 2008;US Wholesale Posted Prices,” Platt’s Oilgram Price Report. August 1,
2006, through January 31, 2007.
a. This is the average Chicago daily terminal price for pure (“neat”) ethanol.
b. This is the average Chicago price for regular gasoline.
c. A gallon of gasoline contains 115,000 British thermal units (Btu) of energy, while a gallon of
ethanol contains 76,000 Btu. Therefore it takes roughly 1.51 gallons of pure ethanol to equal
the Btu content of one gallon of gasoline.
d. The wholesale price difference is computed on a daily basis.
Many proponents and opponents agree that the ethanol industry might not
survive without tax incentives. An economic analysis conducted in 1998 by the Food
and Agriculture Policy Research Institute, concurrent with the congressional debate
over extension of the excise tax exemption, concluded that elimination of the
exemption would cause annual ethanol production from corn to decline roughly 80%
from 1998 levels.45
The tax incentives for ethanol are criticized by some as “corporate welfare,”46
encouraging the inefficient use of agricultural and other resources and depriving the
government of needed revenues.47 In 1997, the General Accounting Office estimated
that the excise tax exemption reduced Highway Trust Fund by $7.5 to $11 billion
over the 22 years from FY1979 to FY2000.48

45 Food and Agriculture Policy Research Institute, Effects on Agriculture of Elimination of
the Excise Tax Exemption for Fuel Ethanol, Working Paper 01-97, April 8, 1997.
46 Erin Hymel, op. cit.
47 U.S. General Accounting Office (GAO), Effects of the Alcohol Fuels Tax Incentives,
March 1997.
48 Jim Wells, GAO, Petroleum and EthanolFuels: Tax Incentives and Related GAO Work,

Proponents of the tax incentive argue that ethanol leads to better air quality and
reduced greenhouse gas emissions, and that substantial benefits flow to the
agriculture sector due to the increased demand for corn to produce ethanol.
Furthermore, they argue that the increased market for ethanol reduces oil imports and
strengthens the U.S. trade balance.
Air Quality
One often-cited benefit of ethanol use is improvement in air quality. The Clean
Air Act Amendments of 1990 (P.L. 101-549) created the Reformulated Gasoline
(RFG) program, which was a major impetus to the development of the U.S. ethanol
industry. The Energy Policy Act of 2005 (P.L. 109-58) made significant changes to
that program that directly affect U.S. markets for gasoline and ethanol.
Before the Energy Policy Act of 2005. Through 2005, ethanol was
primarily used in gasoline to meet a minimum oxygenate requirement for RFG.49
RFG is used to reduce vehicle emissions in areas that are in severe or extreme
nonattainment of National Ambient Air Quality Standards (NAAQS) for ground-
level ozone.50 Ten metropolitan areas, including New York, Los Angeles, Chicago,
Philadelphia, and Houston, are covered by this requirement, and many other areas
with less severe ozone problems have opted into the program, as well.51 In these
areas, RFG is used year-round.
EPA states that RFG has led to significant improvements in air quality,
including a 17% reduction in volatile organic compound (VOC) emissions from
vehicles, and a 30% reduction in emissions of toxic air pollutants.52 Furthermore,
according to EPA, “ambient monitoring data from the first year (1995) of the RFG
program also showed strong signs that RFG is working. For example, detection of
benzene (one of the air toxics controlled by RFG, and a known human carcinogen)
declined dramatically, with a median reduction of 38% from the previous year.”53

48 (...continued)
September 25, 2000.
49 Clean Air Act, Section 211, Subsection k; 42 U.S.C. 7545.
50 Ground-level ozone is an air pollutant that causes smog, adversely affects health, and
injures plants. It should not be confused with stratospheric ozone, which is a natural layer
some 6 to 20 miles above the earth and provides a degree of protection from harmful
51 Under new ozone standards recently promulgated by EPA, the number of RFG areas will
likely increase.
52 The RFG program defines “toxic air pollutants” as benzene, 1,3-butadiene, polycyclic
organic matter, acetaldehyde, and formaldehyde.
53 Margo T. Oge, Director, Office of Mobile Sources, U.S. EPA, Testimony Before the
Subcommittee on Energy and Environment of the Committee on Science, U.S. House of
Representatives, September 14, 1999.

However, the benefits of oxygenates in RFG have been questioned. Although
oxygenates lead to lower emissions of carbon monoxide (CO), in some cases they
may lead to higher emissions of nitrogen oxides (NOX) and VOCs. Since all three
contribute to the formation of ozone, the National Research Council concluded that
while RFG certainly leads to improved air quality, the oxygenate requirement in RFG
may have little overall impact on ozone formation.54 In fact, in some areas, the use
of low-level blends of ethanol (10% or less) may actually lead to increased ozone
formation due to atmospheric conditions in that specific area.55 Some argue that the
main benefit of oxygenates is that they displace other, more dangerous compounds
found in gasoline such as benzene. Furthermore, high gasoline prices have also
raised questions about the cost-effectiveness of the RFG program.
Evidence that the most widely used oxygenate, methyl tertiary butyl ether
(MTBE), contaminates groundwater led to a push by some to eliminate the oxygen
requirement in RFG. MTBE has been identified as an animal carcinogen, and there
is concern that it is a possible human carcinogen. In California, New York, and
Connecticut, MTBE was banned as of January 2004, and several states have followed
Some refiners claimed that the environmental goals of the RFG program could
be achieved through cleaner, although potentially more costly, gasoline that does not
contain any oxygenates.56 These claims added to the push to remove the oxygenate
requirement and allow refiners to produce RFG in the most cost-effective manner,
whether or not that includes the use of oxygenates. However, since oxygenates also
displace other harmful chemicals in gasoline, some environmental groups were
concerned that eliminating the oxygenate requirements would compromise air quality
gains resulting from the current standards. This potential for “backsliding” is a result
of the fact that the current performance of RFG is substantially better than the Clean
Air Act requires. If the oxygenate standard were eliminated, environmental groups
feared that refiners would only meet the requirements of the law, as opposed to
maintaining the current overcompliance. The amendments to the RFG program in
P.L. 109-58 require refiners to blend gasoline in a way that maintains the toxic
emissions reductions achieved in 2001 and 2002.57
Following the Energy Policy Act of 2005. P.L. 109-58 made substantial
changes to the RFG program. Section 1504(a) eliminated the RFG oxygenate
standard as of May 2006, and required EPA to revise its regulations on the RFG

54 National Research Council, Ozone-Forming Potential of Reformulated Gasoline, May,


55 Wisconsin Department of Natural Resources, Bureau of Air Management, Ozone Air
Quality Effects of a 10% Ethanol Blended Gasoline in Wisconsin, September 6, 2005.
56 Al Jessel, Senior Fuels Regulatory Specialist of Chevron Products Company, Testimony
Before the House Science Committee Subcommittee on Energy and Environment, September

30, 1999.

57 P.L. 109-58, Section 1504(b).

program to allow the sale of non-oxygenated RFG. This revision is effective May

6, 2006 in most areas of the country.58

E85 and Air Quality. The air quality benefits from purer forms of ethanol can
be substantial. Compared to gasoline, use of E85 can result in a significant reduction
in ozone-forming vehicle emissions in urban areas.59 And while the use of ethanol
also leads to increased emissions of acetaldehyde, a toxic air pollutant, as defined by
the Clean Air Act, these emissions can be controlled through the use of advanced60
catalytic converters. However, as stated above, purer forms of ethanol have not
been widely used.
Energy Consumption
and Greenhouse Gas Emissions
Energy Balance. A frequent argument for the use of ethanol as a motor fuel
is that it reduces U.S. reliance on oil imports, making the U.S. less vulnerable to a
fuel embargo of the sort that occurred in the 1970s. To analyze the net energy
consumption of ethanol, the entire fuel cycle must be considered. The fuel cycle
consists of all inputs and processes involved in the development, delivery and final
use of the fuel. For corn-based ethanol, these inputs include the energy needed to
produce fertilizers, operate farm equipment, transport corn, convert corn to ethanol,
and distribute the final product. According to a fuel-cycle study by Argonne National
Laboratory, with current technology the use of corn-based E10 leads to a 3%
reduction in fossil energy use per vehicle mile relative to gasoline, while use of E8561
leads to roughly a 40% reduction in fossil energy use.
However, other studies question the Argonne study, suggesting that the amount
of energy needed to produce ethanol is roughly equal to the amount of energy
obtained from its combustion. Since large amounts of fossil fuels are used to make
fertilizer for corn production and to run ethanol plants, ethanol use could lead to little
or no net reduction in fossil energy use. Nevertheless, a recent meta-study of

58 Environmental Protection Agency, “Regulation of Fuels and Fuel Additives: Removal of
Reformulated Gasoline Oxygen Content Requirement and Revision of Commingling
Prohibition to Address Non-Oxygenated Reformulated Gasoline, Direct Final Rule,” 71
Federal Register 8973, February 22, 2006.
59 It should be noted that the overall fuel-cycle ozone-forming emissions from corn-based
E85 are roughly equivalent to those from gasoline. However, some of the emissions
attributable to E85 are in rural areas where corn is grown and the ethanol is produced —
areas where ozone formation is potentially less of a concern. Norman Brinkman and Trudy
Weber (General Motors Corporation), Michael Wang (Argonne National Laboratory), and
Thomas Darlingon (Air Improvement Resource, Inc.), Well-to-Wheels Analysis of Advanced
Fuel/Vehicle Systems — A North American Study of Energy Use, Greenhouse Gas
Emissions, and Criteria Pollutant Emissions, May 2005.
60 California Energy Commission, Ethanol-Powered Vehicles.
61 M. Wang, C. Saricks, and D. Santini, “Effects of Fuel Ethanol on Fuel-Cycle Energy and
Greenhouse Gas Emissions,” Argonne National Laboratory, January 1999.

research on ethanol’s energy balance and greenhouse gas emissions found that most
studies give corn-based ethanol a slight positive energy balance.62 However, because
most of the energy used to produce ethanol comes from natural gas or electricity,
most studies conclude that overall petroleum dependence (as opposed to energy
dependence) can be significantly diminished through expanded use of ethanol.
Despite the fact that ethanol displaces gasoline, the benefits to energy security
from corn-based ethanol are not certain. As stated above, fuel ethanol only accounts
for approximately 2.5% of gasoline consumption in the United States by volume. In
terms of energy content, ethanol accounts for approximately 1.5%. This small
market share led the Government Accountability Office (formerly the General
Accounting Office) to conclude that the ethanol tax incentive has done little to
promote energy security.63 Further, as long as ethanol remains dependent on the U.S.
corn supply, any threats to this supply (e.g., drought), or increases in corn prices,
would negatively affect the supply and/or cost of ethanol. In fact, that happened
when high corn prices caused by strong export demand in 1995 contributed to an

18% decline in ethanol production between 1995 and 1996.

Cellulosic Ethanol Energy Balance. Because cellulosic feedstocks require
far less fertilizer for their production, the energy balance and other benefits of
cellulosic ethanol could be significant. The Argonne study concluded that with
advances in technology, the use of cellulose-based E10 could reduce fossil energy
consumption per mile by 8%, while cellulose-based E85 could reduce fossil energy
consumption by roughly 70%.64
Greenhouse Gas Emissions. Directly related to fossil energy consumption
is the question of greenhouse gas emissions. Proponents of ethanol argue that over
the entire fuel cycle it has the potential to reduce greenhouse gas emissions from
automobiles relative to gasoline, therefore reducing the risk of possible global
Fuel Cycle Analysis. Because ethanol contains carbon,65 combustion of the
fuel necessarily results in emissions of carbon dioxide (CO2), the primary greenhouse
gas. Further, greenhouse gases are emitted through the production and use of
nitrogen-based fertilizers, as well as the operation of farm equipment and vehicles
to transport feedstocks and finished products. However, since photosynthesis (the
process by which plants convert light into chemical energy) requires absorption of
CO2, the growth cycle of the feedstock crop can serve — to some extent — as a
“sink” to absorb some fuel-cycle greenhouse emissions.
According to the Argonne study, overall fuel-cycle greenhouse gas emissions
from corn-based E10 (measured in grams per mile) are approximately 1% lower than

62 Farrell, et al., p. 506.
63 U.S. General Accounting Office, Effects of the Alcohol Fuels Tax Incentives, March 1997.
64 Wang, et al., table 7.
65 The chemical formula for ethanol is C2H5OH.

from gasoline, while emissions are approximately 20% lower with E85.66 Other
studies that conclude higher fuel-cycle energy consumption for ethanol production
also conclude higher greenhouse gas emissions for the fuel. The meta-study on
energy consumption and greenhouse gas emissions concluded that pure ethanol
results in 13% lower greenhouse gas emissions, with approximately a 10% reduction
using E85.67
Fuel Cycle Emissons from Cellulosic Ethanol. Because of the limited
use of fertilizers, fossil energy consumption — and thus greenhouse gas emissions
— is significantly reduced with ethanol production from cellulosic feedstocks. The
Argonne study concludes that with advances in technology, cellulosic E10 could
reduce greenhouse gas emissions by 7% to 10% relative to gasoline, while cellulosic68
E85 could reduce greenhouse gas emissions by 67% to 89%. The meta-study of
energy consumption and greenhouse gas emissions found a similar potential for69
greenhouse gas reductions.
Lifecycle Analysis. A key criticism of fuel-cycle analyses is that they
generally do not take changes in land use into account. For example, if a previously
uncultivated piece of land is tilled to plant biofuel crops, some of the carbon stored
in the field could be released. In that case, the overall GHG benefit of biofuels could
be compromised. One study estimates that taking land use into account (a lifecycle
analysis as opposed to a fuel-cycle analysis), the GHG reduction from corn ethanol70
is less than 3% per mile relative to gasoline, while cellulosic biofuels have a
life-cycle reduction of 50%.71 Other recent studies indicate even smaller GHG
This is of key interest because under the RFS, as amended by P.L. 110-140, to
qualify under the mandate, all fuels from new biofuel refineries must achieve at least
a 20% reduction in lifecycle greenhouse gas emissions. Further, to qualify as
advanced biofuels, they must achieve a 50% reduction in lifecycle emissions. EPA
is tasked with developing regulations to rate fuels on their lifecycle emissions, and
determining which fuels qualify under the new standard.

66 Wang, et al., table 7.
67 Farrell, et al., p. 506.
68 Wang, et al., table 7.
69 Farrell, et al., p. 507.
70 Mark A. Delucchi, Draft Report: Life cycle Analyses of Biofuels. 2006.
71 While a 50% life-cycle reduction is still significant, it is far less than the 90% reduction
suggested by fuel-cycle analyses.

Policy Concerns and Congressional Activity
Recent congressional interest in ethanol fuels has mainly focused on six policies
and issues: (1) the renewable fuel standard; (2) “boutique” fuels; (3) the alcohol fuel
tax incentives; (4) ethanol imports through Caribbean Basin Initiative (CBI)
countries; (5) fuel economy credits for dual fuel vehicles; and (6) the role of biofuels
in the upcoming Farm Bill. In the 109th and 110th Congresses, several of these issues
were debated during consideration of the Energy Policy Act of 2005 (P.L. 109-58)
and the Energy Independence and Security Act of 2007 (P.L. 110-140).
Renewable Fuel Standard (RFS)
The renewable fuels standard requires motor fuel to contain a minimum amount
of fuel produced from renewable sources such as biomass, solar, or wind energy.
Proposals to establish an RFS gained traction as part of the discussion over
comprehensive energy policy. Supporters argued that demand for ethanol creates
jobs, and that there are major environmental and energy security benefits to using
renewable fuels. However, opponents argued that any renewable fuel standard would
only exacerbate a situation of artificial dS. emand for ethanol created by tax
incentives and fuel quality standards. Any requirement above the existing level for
ethanol would require the construction and/or expansion of ethanol plants, and likely
would lead to increased fuel prices and further instability in an already tight fuel
supply chain. Further, they argued that a renewable fuel standard would lead to
increased corn prices caused by higher demand.
On August 8, 2005, President Bush signed the Energy Policy Act of 2005 (P.L.
109-58). Section 1501 required the use of at least 4.0 billion gallons of renewable
fuel in 2006, increasing to 7.5 billion gallons in 2012 (see Table 5). Through 2007
the requirement was largely met using ethanol, although other fuels such as biodiesel
played a limited role.72 The law directed EPA to establish a credit trading system to
provide flexibility to fuel producers. Further, under the RFS, ethanol produced from
cellulosic feedstocks was granted extra credit: a gallon of cellulosic ethanol counted
as 2.5 gallons of renewable fuel under the RFAlso, P.L. 109-58 required that 250
million gallons of cellulosic ethanol be blended in gasoline annually starting in73
2013. The Energy Independence and Security Act of 2007 (P.L. 110-140), signed
by President Bush on December 19, 2007, significantly expanded the RFS, requiring
the use of 9.0 billion gallons of renewable fuel in 2008, increasing to 36 billion
gallons in 2022. Further, P.L. 110-140 requires an increasing amount of the mandate
be met with “advanced biofuels” — biofuels produced from feedstocks other than
corn starch (and with 50% lower lifecycle greenhouse gas emissions than petroleum
fuels). Within the advanced biofuel mandate, there are specific carve-outs for
cellulosic biofuels and bio-based diesel substitutes (e.g., biodiesel).

72 Biodiesel is a synthetic diesel fuel made from oils such as soybean oil. For more
information, see CRS Report RL30758, Alternative Transportation Fuels and Vehicles:
Energy, Environment, and Development Issues, by Brent D. Yacobucci.
73 Currently, world production of cellulosic ethanol is limited. No plants currently exist in
the United States, although some small plants are in the planning phase.

Table 5. Expanded Renewable Fuel Standard Requirements
Under P.L. 110-140
Advanced Cellulosic
Expanded B i of uel B i of uel B i omass-
PreviousRFSMandateMandateBased Diesel
RFS (billion(billion(billiona(billionbFuel (billionb
Year gallons ) gallons ) gallons ) gallons ) gallons )
2009 6.1 11.1 0.6 0.5
2010 6.8 12.95 0.95 0.1 0.65
2011 7.4 13.95 1.35 0.25 0.8
2012 7.5 15.2 2.0 0.5 1.0
20137.6 (est.)16.552.751.01.0
20147.7 (est.)18.153.751.751.0
20157.8 (est.)
20167.9 (est.)
20178.1 (est.)
20188.2 (est.)
20198.3 (est.)
20208.4 (est.)
20218.5 (est.)
20228.6 (est.)
a. The advanced biofuel (i.e., non-corn-starch ethanol) mandate is a subset of the expanded RFS. The
difference between the expanded RFS mandate and the advanced biofuel mandate — 15 billion
gallons in 2015 onward) is effectively a cap on corn ethanol.
b. The cellulosic biofuel and biomass-based diesel fuel mandates are subsets of the advanced biofuel
ma nd ate.
Ethanol producers are rapidly expanding capacity in order to meet the increased
demand created by the RFS. Between January 2005 and January 2008, U.S. ethanol
production capacity expanded from 3.6 billion gallons per year to 7.2 billion gallons
per year.
EPA is required to establish a system for suppliers to generate and trade credits
earned for exceeding the standard in a given year. Credits can then be purchased by
other suppliers to meet their quotas. On May 1, 2007, EPA released a final

rulemaking for 2007 and beyond. Included in the rule were provisions for credit
trading, as well as provisions for generating credits from the sale of biodiesel and
other fuels.74 Because of the changes in the RFS from P.L. 110-140, EPA will need
to publish new rules to reflect those changes. Perhaps most importantly, EPA will
need to develop rules for determining the lifecycle greenhouse gas emissions (see
“Greenhouse Gas Emissions,” above). Fuels from new biorefineries must achieve
at least a 20% lifecycle greenhouse gas reduction relative to petroleum fuels, and
advanced biofuels must achieve at least a 50% reduction.
The effects of such an increase in ethanol production could be significant,
especially if that ethanol comes from corn.75 These effects include increased corn
demand and higher corn prices, leading to higher costs for food (especially in places
where corn is a significant part of the local diet) and higher animal feed prices (and
higher meat prices). Expanded ethanol use could also strain an already tight ethanol
distribution system that is dependent on rail cars for transport, since ethanol may not
be transported by pipeline in the United States. Other concerns include the potential
for increased water use for corn cultivation and the increased use of chemical
fertilizers and pesticides.76
“Boutique” Fuels77
As a result of the federal reformulated gasoline requirements, as well as related
state and local environmental requirements, gasoline suppliers may face several
different standards for gasoline quality in different parts of one state or in adjacent
states. These different standards sometimes require a supplier to provide several
different fuel formulations in a region.78 These different formulations are sometimes
referred to as “boutique” fuels.79 Because of varying requirements, if there is a
disruption to the supply of fuel in one area, refiners producing fuel for other nearby
areas may not be able to supply fuel quickly enough to meet the increased demand.

74 Environmental Protection Agency, “Regulation of Fuels and Fuel Additives: Renewable
Fuel Standard Program; Final Rule,” 72 Federal Register 23899-23948, May 1, 2007.
75 For more information, see CRS Report RL33928, Ethanol and Biofuels: Agriculture,
Infrastructure, and Market Constraints Related to Expanded Production, by Brent
Yacobucci and Randy Schnepf.
76 For more information on some of the potential concerns from an expanded RFS, see CRS
Report RL34265, Selected Issues Related to an Expansion of the Renewable Fuel Standard
(RFS), by Brent D. Yacobucci and Tom Capehart.
77 For more information on boutique fuels, see CRS Report RL31361, “Boutique Fuels” and
Reformulated Gasoline: Harmonization of Fuel Standards, by Brent D. Yacobucci.
78 These various formulations should not be confused with gasoline “grades” — “regular,”
“mid-grade,” and “premium” octane level fuels — which are not required by federal law but
are desired by consumers and required in some engine designs.
79 EPA, Office of Transportation and Air Quality, Staff White Paper: Study of Unique
Gasoline Fuel Blends (“Boutique Fuels”), Effects on Fuel Supply and Distribution and
Potential Improvements, October 2001.

EPA conducted a study on the effects of harmonizing standards and released a
staff white paper in October 2001.80 EPA modeled several scenarios, some with
limited changes to the existing system, others with drastic changes. In its preliminary
analysis, EPA concluded that some minor changes could be made that might mitigate
supply disruptions without significantly increasing costs or adversely affecting
vehicle emissions. However, all of the changes modeled in EPA’s study would
require amendments to various provisions in the Clean Air Act.
Congressional interest has centered on the question of whether the various
standards could be harmonized to reduce the number of gasoline formulations.
Section 1504(c) of P.L. 109-58 consolidates two summertime RFG formulations into
one fuel, eliminating one class of fuel. Further, P.L. 109-58 prohibits the number of
state fuel blends from exceeding the number as of September 1, 2004. However,
many of the larger systemic issues were not addressed.
Alcohol Fuel Tax Incentives81
As stated above, the ethanol tax incentives are controversial. The incentives
allow fuel ethanol to compete with other additives, since the wholesale price of
ethanol is so high. Proponents of ethanol argue that the incentives lower dependence
on foreign imports, promote air quality, and benefit farmers.82
Opponents argue that the tax incentives support an industry that could not exist
on its own. Despite objections from opponents, Congress in 1998 extended the
motor fuels excise tax exemption through 2007, but at slightly lower rates.83 To
eliminate concerns over Highway Trust Fund revenue losses, the 108th Congress
replaced the excise tax exemption with an income tax credit, effectively transferring
the effects of the incentive from the Highway Trust Fund to the general treasury, and
extending the incentive through 2010.84
Ethanol Imports
There is growing concern over ethanol imports among some stakeholders.
Because of lower production costs and/or government incentives, ethanol prices in
Brazil and other countries can be significantly lower than in the United States. To
offset the U.S. tax incentives that all ethanol (imported or domestic) receives, most
imports are subject to a relatively small 2.5% ad valorem tariff, but more

80 Harmonization refers to an attempt to aggregate fuels with similar requirements under a
single requirement, thus limiting the number of possible formulations.
81 For more information, see CRS Report RL32979, Alcohol Fuels Tax Incentives, by
Salvatore Lazzari.
82 U.S. General Accounting Office (GAO), Effects of the Alcohol Fuels Tax Incentives,
March 1997.
83 P.L. 105-178.
84 P.L. 108-357.

significantly an added duty of $0.54 per gallon. This duty effectively negates the tax
incentives for covered imports, and has been a significant barrier to ethanol imports.
However, under certain conditions imports of ethanol from Caribbean Basin
Initiative (CBI) countries are granted duty-free status.85 This is true even if the
ethanol was actually produced in a non-CBI country. In this scenario the ethanol is
dehydrated in a CBI country, then shipped to the United States.86 This avenue for
avoiding the duty by imported ethanol has been criticized by some stakeholders,
including some Members of Congress.
On December 20, 2006, President Bush signed the Tax Relief and Health Care
Act of 2006 (P.L. 109-432). Among other provisions, the act extended the duty on
imported ethanol through December 31, 2008.
Fuel Economy Credits for Dual Fuel Vehicles
The Energy Policy and Conservation Act (EPCA) of 197587 requires Corporate
Average Fuel Economy (CAFE) standards for motor vehicles.88 Under EPCA, the
average fuel economy of all vehicles of a given class that a manufacturer sells in a
model year must be equal to or greater than the standard for that class. These
standards were first enacted in response to the desire to reduce petroleum
consumption and promote energy security after the Arab oil embargo. The model
year 2007 standard for passenger cars is 27.5 miles per gallon (mpg), while the
standard for light trucks is 22.2 mpg.
EPCA (and subsequent amendments to it) provides manufacturing incentives
for alternative fuel vehicles, including ethanol vehicles.89 For each alternative fuel
vehicle a manufacturer produces, the manufacturer generates credits toward meeting
the CAFE standards. These credits can be used to increase the manufacturer’s
average fuel economy. Credits apply to both dedicated and dual fuel vehicles. Dual
fuel vehicles can be operated on both a conventional fuel (gasoline or diesel) and an
alternative fuel, usually ethanol. Opponents have raised concerns that while
manufacturers are receiving credits for production of these dual fuel vehicles, they
are generally operated solely on gasoline, because of the cost and unavailability of
alternative fuels. This claim is supported by the fact that EIA estimates that only

85 The CBI countries include Costa Rica, Jamaica, and El Salvador, which represent a
significant percentage of U.S. fuel ethanol imports. For more information on ethanol
imports from CBI countries, see CRS Report RS21930, Ethanol Imports and the Caribbean
Basin Initiative, by Brent D. Yacobucci.
86 Dehydration is the final step in the ethanol production process. Excess water is removed
from the ethanol to make it usable as motor fuel. For more information, see section above
on “Ethanol Refining and Production.”
87 P.L. 94-163.
88 For more information on CAFE standards, see CRS Report RL33413, Automobile and
Light Truck Fuel Economy: The CAFE Standards, by Brent D. Yacobucci and Robert
89 49 U.S.C. 32905.

about 2% of flexible fuel vehicles are currently operated on E85. Supporters of the
credits counter that the incentives are necessary for the production of alternative fuel
vehicles, and that as the number of vehicles increases, the infrastructure for
alternative fuels will grow. However, the success of this strategy has been limited
to date.
The credits were set to expire at the end of the 2004 model year. However, in
2004 the Department of Transportation (DOT) issued a final rule extending the
credits through model year 2008.90 Section 772 of P.L. 109-58 extended the credits
through model year 2010, and extended DOT’s authority (to continue the credits)
through 2014.
The 2008 Farm Bill
It is expected that the 110th Congress will reauthorize existing farm programs
and promote new programs as part of a new Farm Bill. Most of the provisions of the
most recent Farm Bill — The Farm Security and Rural Investment Act of 2002 (P.L.

107-171) — expired in 2007. On July 27, 2007, the House approved a new farm bill,

H.R. 2419. Title IX would expand and extend several provisions from the 2002 farm
bill’s energy title, with substantial increases in funding and a heightened focus on
developing cellulosic energy production, and a move away from corn-starch-based
ethanol. The Senate passed its version on December 14, 2007. The Senate version
would expand 2002 Farm Bill programs, create new tax incentives for cellulosic
ethanol, and require studies on expanded biofuel infrastructure. As of March 2008,
a conference on the House and Senate bills was pending.91
Although the use of fuel ethanol has been limited to date (only about 3% to 5%
of gasoline consumption), it has the potential to significantly displace petroleum
demand. However, the overall benefits in terms of energy consumption and
greenhouse gases are limited, especially in the case of corn-based ethanol. With only
a slight net energy benefit from the use of corn-based ethanol, transportation energy
demand is essentially transferred from one fossil fuel (petroleum) to another (natural
gas and/or coal). There may be strategic benefits from this transfer, especially if the
replacement fuel comes from domestic sources or from foreign sources in more
stable areas. However, the benefits in terms of greenhouse gas emissions reductions
is limited.
Cellulosic feedstocks have the potential to dramatically improve the benefits of
fuel ethanol. Their use could significantly decrease the energy (from all sources)
required to produce the fuel, as well as decreasing associated greenhouse gases.

90 60 Federal Register 7689, February 19, 2004.
91 For more information on biofuel provisions in the Farm Bill, see CRS Report RL34239,
Biofuels in the 2007 Energy and Farm Bills: A Side-by-Side Comparison, by Brent D.
Yacobucci, Randy Schnepf, and Tom Capehart.

However, technologies to convert cellulose to ethanol at competitive costs seem
distant. For this reason, there is wide support for increased federal R&D.
Federal incentives for ethanol use — including tax incentives, the RFG
oxygenate standard, and the renewable fuels standard — have promoted significant
growth in the ethanol market. Annual U.S. ethanol production increased from 175
million gallons in 1980 to 6.8 billion gallons in 2007, largely as a result of these
incentives. Federal incentives drive demand for the fuel, as well as making its price
competitive with gasoline.
Enacted as part of the Energy Policy Act of 2005 and expanded by the Energy
Independence and Security Act of 2007, the renewable fuels standard will continue
to drive growth in the ethanol market, as it mandates a minimum annual amount
(increasing yearly) of renewable fuel in gasoline. While other fuels will be used to
some extent to meet the standard, the a large share of the mandate will be met with
ethanol. The increasing demand for ethanol may lead to price pressures on motor
fuel. These price pressures — and ethanol supply concerns in general — could
increase interest in eliminating the tariff on imported ethanol.
Congress will likely continue to show interest in ethanol’s energy and
environmental costs and benefits, as well as its effects on U.S. fuel markets. Any
discussion of U.S. energy policy includes promotion of alternatives to petroleum.
With limited petroleum supplies, high prices, and instability in some oil-producing
regions, these discussions are unlikely to end any time soon.