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March 18, 2015 Subject: Role of E15 in Reducing GHG Emissions To Whom it May Concern: Below I am providing a technical assessment of the greenhouse gas (GHG) emissions impact of converting 23.4 billion gallons of E10 gasoline to E15 across a 7 state area. In this analysis I am using the carbon intensity (CI) unit commonly used for life cycle assessments of fuels. The CI of a fuel is generally stated as the mass of carbon dioxide equivalent (including carbon dioxide, nitrous oxide, and methane) emitted per energy unit of fuel. The common unit is gCO2e/MJ. The CI of a fuel is determined by adding the emissions incurred along its production pathway for the product life cycle including fuel feedstock origination (e.g. drilling, mining, corn growing), feedstock conversion at refineries, and combustion in the vehicle. For biofuels, in particular, the land requirements for feedstock production can also produce emissions and/or sequestration effects from carbon stock adjustments. Computable economic equilibrium models are often used to determine land use change (LUC) prompted by biofuels production and the assessed LUC is subsequently multiplied by carbon stock emissions factors specific to ecosystem changes to derive LUC carbon emissions associated with a particular biofuels pathway. New processing technologies as well as updated life cycle models and databases accessed by computable general equilibrium models have significantly advanced the CI assessments of biofuels over the last 10 years. For corn ethanol, for example, the following research updates have occurred:

1) LUC Carbon Emissions

Published studies on LUC emissions have shown a significant reduction in the predicted carbon

emission magnitude over time. This downward trend in predicted emissions is due to several

factors in improved CGE models including 1) an evolving understanding of the elasticity of land

transitions and yield-price relationships, 2) better addressing of ethanol co-product

substitutions in animal feed markets, 3) better understanding and data availability of global land

types, and 4) carbon adjustments during land transitions.

Energy Resources Center (MC 156)

Agriculture and Bioenergy Research Center

1309 South Halsted

Chicago, Illinois 60607-7022

www.erc.uic.edu

Phone (312) 355-3982 ● Fax (312) 996-5620

Figure 1: Predicted Land Use Change Emissions by Different Studies Over Time

2) Technology Innovation at the Biorefinery

The use of fossil energy at the biorefinery is a significant contributor to the CI of ethanol.

Published surveys of the ethanol industry showed that 2008 ethanol plants use 30% less energy

to convert corn to ethanol than 2001-era plants.1 A recent follow up survey showed further

energy reductions.2

3) Technology Innovation in Feedstock Agriculture

Emerging agricultural practices and technologies have been shown to further reduce land

demands and emissions from biofuels production. Most noteworthy are applications of

nitrification inhibitors which stabilize nitrogen fertilizer inputs (a market that has seen 20% year

over year growth for the last 5 years), advanced hybrid seeds, and precision agriculture.

4) Updated Modeling

The Argonne CCLUB greenhouse gas emissions model from biofuels production incorporates

detailed carbon stock factors for different ecosystems that enable an exhaustive analysis of

carbon emissions and sequestration from LUC. For selected modeling runs (that take realistic,

projected crop yield increases into account) the LUC emissions in CCLUB for corn ethanol total 7-

9.0 gCO2e/MJ (as opposed to 28 gCO2e/MJ used by EPA for corn ethanol). 3,4

1 Mueller, S. (2010). 2008 National dry mill corn ethanol survey. Biotechnology Letters, 32, 1261-1264. 2 Mueller, S. and John Kwik. Corn Ethanol: Emerging Plant Energy and Environmental Technologies, 2012, available at

www.erc.uic.edu 3 Ho-Young Kwon, Steffen Mueller, Jennifer B. Dunn, Michelle M. Wander; Modeling state-level soil carbon emission factors

under various scenarios for direct land use change associated with United States biofuel feedstock production; Biomass and

Bioenergy (2013), http://dx.doi.org/10.1016/j.biombioe.2013.02.021 4 Jennifer B Dunn, Steffen Mueller, Ho-young Kwon and Michael Q Wang; Land-use change and greenhouse gas emissions from

corn and cellulosic ethanol; Biotechnology for Biofuels 2013, 6:51 doi:10.1186/1754-6834-6-51; Published: 10 April 2013

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5) Greenhouse Gas Savings from E15 Sales in the City of Chicago

Recent Argonne GREET life cycle emissions analyses estimate that corn ethanol greenhouse gas emissions are 19-48% (mean=34%) lower than conventional gasoline.5 Each gallon of E15 saves 1.25 gCO2e/MJ over E10 on a life cycle basis. At the modeled conversion of 23.4 billion gallons of E10 gasoline to E15 gasoline the CO2 savings for the seven state area would total 3.41 million metric tonnes CO2e annually. The total CO2 savings from ethanol blended into that fuel supply relative to E0 amount to 9.91 million metric tonnes. If only half of the modeled fuel gallons switch from E10 to E15 then the total savings across the seven state area total 1.71 million metric tonnes. Table 1: Emissions Savings Assuming 100% Transition to E15 Blends6

Gallons

Metric Tonnes CO2e

E10-E15 (100% Switch)

Metric Tonnes CO2e

E0-E15 (100% Switch)

Iowa 1,515,276,000 220,821.62 641,834.72

Illinois 4,553,934,000 663,646 1,928,938

Kansas 1,264,158,000 184,226 535,467

North Carolina 4,239,816,000 617,870 1,795,885

Ohio 4,880,106,000 711,179 2,067,096

Michigan 4,536,126,000 661,051 1,921,395

Wisconsin 2,410,422,000 351,272 1,020,997

Total: 23,399,838,000 3,410,065 9,911,612 Table 2: Emissions Savings Assuming 50% Transition to E15 Blends

Gallons

Metric Tonnes CO2e

E10-E15 (50% Switch)

Iowa 757,638,000 110,411

Illinois 2,276,967,000 331,823

Kansas 632,079,000 92,113

North Carolina 2,119,908,000 308,935

Ohio 2,440,053,000 355,590

Michigan 2,268,063,000 330,525

Wisconsin 1,205,211,000 175,636

Total: 11,699,919,000 1,705,033

5 Wang, M., et al (2012) Well-to-wheels energy use and greenhouse gas emissions of ethanol from corn, sugarcane and cellulosic

biomass for US use. Environ. Res. Lett. 7 045905 6 Gasoline gallons per state provided by Smoot Tewes Group.

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Table 3: CI of Different Fuels

Finished Gasoline

gCO2/MJ

E15 over E10

Savings

gCO2e/MJ

E15 over E0

Savings

gCO2e/MJ

E15 94.36 1.25 3.64

E10 95.61

E0 98.00 I hope this analysis provides some scientific illumination on this topic. Please do not hesitate to contact me by phone at 312-316-3498 or by email at muellers@uic.edu if you have any further questions. Sincerely,

Steffen Mueller, PhD Principal Research Economist Energy Resources Center Director, Agriculture and Bioenergy Research Center University of Illinois at Chicago