USEPA’s Regulatory Action 

under the 

Energy Independence and Security 

Act 

March 2008

Bob Larson, 

Transportation and Climate Div

USEPA
Recent Events

 August 2005 Energy Act – requires 7.5 b gals renewable 

fuel by 2012

 January 2007 State of the Union Address—20-in-10 

goal

 March 2007 Administration proposes Alternative 

Fuel Standard legislation

 April 2007 Supreme Court Decision

 May 2007 EPA adopts 7.5 b gal renewable fuel regulations

 May 2007 President’s Announcement and 

Executive Order (35 billion gallons renewable 

and alternative fuel)

 December 2007 Energy Independence and Security Act passed 

by Congress and signed by President Bush, 

including a 36 billion gallon renewable fuel mandate
EISA has two major components 

related to GHG from transportation

 Improvements in vehicle fuel efficiency 

(reaching approximately 35MPG on avg by 

2022)

 Greatly increases the amount of 

renewable fuel compared to the 2005 

energy act
4 Separate Standards

Year Advanced Biofuel Total 

Renewable 

Fuel

BiomassBased DieselCellulosic 

Biofuel

Total 

Advanced 

Biofuel

2006 4.0

2007 4.7

2008 9.0

2009 0.5 0.6 11.1

2010 0.65 0.1 0.95 12.95

2011 0.80 0.25 1.35 13.95

2012 1.0 0.5 2.0 15.2

2013 1.0 1.0 2.75 16.55

2014 1.0 1.75 3.75 18.15

2015 1.0 3.0 5.5 20.5

2016 1.0 4.25 7.25 22.25

2017 1.0 5.5 9.0 24.0

2018 1.0 7.0 11.0 26.0
The Standards are Nested

Shown with 2022 volumes

Renewable fuels - 36 bill gal

 Mostly corn-ethanol

 Also other fuels which

 meet GHG reduction

 threshold of 20%

Advanced biofuels - 21 bill gal

Cellulosic biofuel - 16 bill gal

Mostly cellulosic ethanol

All fuels must meet GHG

reduction threshold of 60%

Mostly imported ethanol

Some renewable diesel

All fuels must meet GHG 

reduction threshold of 50%

Biomassbased 

diesel

1 bill gal

Biodiesel

All fuels must meet GHG 

reduction threshold of 50%
Energy Independence and Security 

Act Requires Lifecycle Assessment

 Lifecycle assessment required to 

determine which fuels meet mandated 

GHG performance thresholds compared to 

petroleum fuel replaced

 20% reduction for new facility renewable fuel

 50% reduction for biomass-based diesel

 60% reduction for cellulosic biofuel

 Lifecycle assessment must include 

impacts on land use
Fuel Life Cycle GHG Assessment

 Also called fuel cycle or well-to-wheel 

analysis, compilation of the GHG impacts 

of a fuel throughout its life cycle

 Production / extraction of feedstock

 Feedstock transportation

 Fuel production

 Fuel distribution

 Tailpipe emissions

 Can be used to compare one or more 

fuels performing the same function (e.g., 

miles driven)
Corn Ethanol Example

Can compare to producing an equivalent amount 

of petroleum gasoline

Fertilizer N2O

Fuel Combustion CO2

Land Use Change CO2 Fuel Combustion CO2 Fuel Combustion CO2 Fuel Combustion CO2

 1 gal ethanol

Corn Farming 0.37 bu Corn Trans Ethanol Production Ethanol Dist

GHG Emissions 6.5 lb DDGS*

 Reduced GHG Emissions

 = 0.16 bu corn (~9 lb) plus

 0.4 lb soybean meal

Ag Chemical Prod

Natural Gas Natural Gas Diesel Fuel Natural Gas Diesel Fuel 

LPG Coal 

Electricity Electricity 

Diesel Fuel

Gasoline

* Displacement allocation used, so for entire system new corn production = 0.21 bu and results in 0.4 less soybean meal produced

DDGS = Distiller Dried Grains, substitute animal feed
Example: Gasoline vs. Corn Ethanol Lifecycle 

Comparison From RFS 1

Gasoline Lifecycle GHG Emissions

Lifecycle GHG 

Emissions 99,300

0

20,000

40,000

60,000

80,000

100,000

120,000

Crude

Extraction

Crude Trans Refining Gasoline

T&D

Tailpipe

g C

O2-eq./m

m

Btu

Fossil CO2

N2O

CH4

Cumulative GHG

Corn Ethanol Lifecycle GHG Emissions

Lifecycle GHG 

Emissions 73,300

-100,000

-80,000

-60,000

-40,000

-20,000

0

20,000

40,000

60,000

80,000

100,000

Corn

Farming

Corn Trans Ethanol

Prod

Ethanol

T&D

Tailpipe

g C

O2-eq./m

m

Btu

Fossil CO2

N2O

CH4

Biomass CO2

Co-Prod CO2 Credit

Co-Prod CH4 Credit

Co-Prod N2O Credit

Cumulative GHG

26% 

reduction 

in GHG 

emissions

Comparing 

energy 

equivalent 

amounts of 

fuel

Assumptions: 7.5 

Bgal scenario used in 

the Renewable Fuel 

Standard Rulemaking, 

corn ethanol dry 

milling using natural 

gas
Example Lifecycle Analysis

 Prior Renewable Fuel Standard analysis 

assessed first order impacts

 GHG impacts of corn and soybean acres in US

 New analysis more complete assessment of 

domestic impacts and added international

 Corn and soybeans plus other crops

 Land use changes

 International impact of decreased US exports

• Increased crop production in other countries adds GHG

• Land use impacts critical
Domestic Impact Discussion

 Looking at domestic impacts only of increased ethanol production 

results in a net decrease in total GHG emissions

 Shift in crop production results

in little net crop acreage 

increase in US

 Decrease in rice acres and

livestock production

(due to increased feed prices)

results in GHG emission

reductions

 40% of corn used for ethanol comes from reductions in exports 

(highlighting need to include international impacts)

-2

-1

0

1

2

3

4

Cotton

Corn

Soybeans

Wheat

Sorghum

RiceOats

Barley

Silage

Hay

Net Change

Million A

cre

s
Land Use Change 

Assumptions

 Need to consider carbon per acre for different land types

 What type of land is converted in different countries, for 

example:

 Argentina (Savanna)

 Brazil Case 1 (Pasture)

 Brazil Case 2 (Savanna)

 Brazil Case 3 (Pasture + Tropical Forest)

 Indonesia (Tropical Forest)

One Time Release

0

50

100

150

200

250

Pasture Savanna Tropical Forest

Metric T

on C

O2 / Acre
Impact of Land Use Change Assumptions

(Dry Mill, Natural Gas, Dry and Pelletized DDGS)

NET + 28%

NET - 11% 

NET - 17%

-40,000

-20,000

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

Gasoline Ethanol (Brazil

Pasture)

Ethanol (Brazil

Savanna)

Ethanol (Brazil

Forest + Pasture)

g

C

O2-eq./m

m

Btu

-140%

-120%

-100%

-80%

-60%

-40%

-20%

0%

20%

40%

60%

Percent Change fro

m

Gasoline

International Rice

Methane

International Livestock

Decreases

International Land Use

Change

International Farm Inputs

and Fert N2O

Domestic Rice Methane

Domestic Livestock

Decreases

Domestic Soil Carbon

Change

Domestic Farm Inputs

and Fert N2O

Other (fuel and feedstock

transport)

Fuel Prod - Dry Mill NG

Total Net GHG

Emissions
Further Work on Life Cycle 

Modeling

 Specific areas of improvement that we are working on include:

 Building a consistent modeling framework that captures both 

domestic and international agricultural sector changes and GHG 

impacts

 Working with experts to improve understanding of agricultural 

N2O emissions

 Developing country specific GHG emissions factors associated 

with land use change and agricultural practices

 Updating petroleum baseline

 Updating other biofuel life cycle GHG factors with this 

approach

 Biodiesel

 Imported ethanol

 Cellulosic ethanol

 We continue to have discussions with

 Industry groups

 Academics and other experts