Office of Transportation and Air Quality

EPA-420-F-12-078

November 2012

EPA Issues Supplemental Determination 

for Renewable Fuels Produced under 

the Final RFS2 Program from Grain 

Sorghum

The U.S. Environmental Protection Agency (EPA) is issuing a 

supplemental rule associated with the Renewable Fuel Standard 

(RFS) program. This final rule contains a lifecycle greenhouse gas 

(GHG) analysis for grain sorghum ethanol and a regulatory determination that grain sorghum ethanol qualifies as a renewable fuel under 

the RFS Program.

EPA’s analysis indicates that ethanol made from grain sorghum at dry 

mill facilities that use natural gas for process energy meets the lifecycle GHG emissions reduction threshold of 20% compared to the 

baseline petroleum fuel it would replace, and therefore qualifies as 

a renewable fuel. It also contains our regulatory determination that 

grain sorghum ethanol produced at dry mill facilities using specified 

forms of biogas for both process energy and most electricity production, has lifecycle GHG emission reductions of more than 50% compared to the baseline petroleum fuel it would replace, and that such 

grain sorghum ethanol qualifies as an advanced biofuel under the RFS 

program.

General Background

In the March, 2010 RFS2 final rule, EPA assessed the lifecycle GHG emissions of 

multiple renewable fuel pathways (defined as feedstock, fuel type, and fuel production process). Assessment of lifecycle GHG emissions is necessary to determine 

Regulatory Announcement

which fuel pathways meet the GHG reduction thresholds for the four renewable fuel 
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categories specified in Clear Air Act (CAA) Section 211 (o), as amended by the Energy Independence and Security Act of 2007 (EISA). The CAA requires a 20% reduction in lifecycle 

GHG emissions for renewable fuel produced at new facilities (those constructed after EISA 

enactment), a 50% reduction for biomass-based diesel or advanced biofuel, and a 60% reduction 

for cellulosic biofuel.

Assessing whether a fuel pathway meets these thresholds requires a comprehensive evaluation of 

the lifecycle GHGG emissions of the renewable fuel as compared to the lifecycle GHG emissions of the gasoline or diesel fuel that it replaces. The CAA defines lifecycle GHG emissions 

as follows:

The term ‘lifecycle greenhouse gas emissions’ means the aggregate quantity of greenhouse gas emissions (including direct emissions and significant indirect emissions such 

as significant emissions from land use changes), as determined by the Administrator, 

related to the full fuel lifecycle, including all stages of fuel and feedstock production and 

distribution, from feedstock generation or extraction through the distribution and delivery and use of the finished fuel to the ultimate consumer, where the mass values for all 

greenhouse gases are adjusted to account for their relative global warming potential.1

In the March, 2010 RFS2 final rule, EPA focused our lifecycle analysis on fuels that were anticipated to contribute relatively large volumes of renewable fuel by 2022, and thus did not 

cover all fuels that either are contributing or could potentially contribute to the program. In the 

preamble to the March, 2010 RFS2 final rule, EPA indicated that we would continue to examine several additional pathways not analyzed for the final rule, including those from grain sorghum, and would complete this process through a supplemental rulemaking process. On June 12, 

2012, EPA published a Notice of Data Availability Concerning Renewable Fuels Produced From 

Grain Sorghum Under the RFS Program (see 77 FR 34915). In that notice of data availability, 

we provided an opportunity for comment on EPA’s analysis of grain sorghum used as a feedstock 

to produce ethanol under the RFS program. This supplemental rulemaking finalizes our analysis 

of potential pathways for ethanol produced from a grain sorghum feedstock.

Lifecycle Analysis

In order to calculate lifecycle GHG emissions for the supplemental final rulemaking regarding 

grain sorghum biofuel pathways, EPA utilized models developed for the March, 2010 RFS2 final 

rule. These models take into account energy and emissions inputs for fuel and feedstock production, distribution, and use, as well as economic models that predict changes in agricultural 

markets.

EPA used the same general approach to estimate global land use change GHG emissions from 

using grain sorghum as a feedstock as we have used to analyze other biofuel pathways.

1 Clean Air Act Section 211(o)(1)
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Pathway Determinations

EPA’s analysis found that ethanol produced from grain sorghum has an estimated lifecycle GHG 

emissions reduction of 32% when produced at dry mill ethanol facilities that use natural gas 

and produced an industry average of 92% wet distillers grains, and 52% when produced at dry 

mill ethanol facilities that use only biogas for process energy and purchase/receive from an offsite supplier 0.15 kWh of electricity per gallon of ethanol produced, compared to the baseline 

gasoline fuel it would replace. Therefore, grain sorghum ethanol produced at dry mill ethanol 

facilities using natural gas meets the minimum 20% GHG emissions reduction threshold for 

conventional biofuels, and grain sorghum ethanol produced at plants using only biogas for process energy and purchasing/receiving from an off-site supplier no more than 0.15 kWh of electricity per gallon of ethanol produced, meets the 50% GHG emissions reduction threshold for 

advanced biofuels as required by EISA.

For More Information

You can access documents on RFS regulations on EPA’s Office of Transportation and Air Quality 

(OTAQ) website at:

www.epa.gov/otaq/fuels/renewablefuels/regulations.htm

To submit a question on the RFS program, and to view Frequently Asked Questions, please visit:

www.epa.gov/otaq/fuels/renewablefuels/compliancehelp/index.htm

You can also contact the OTAQ library for document information at:

U.S. Environmental Protection Agency

Office of Transportation and Air Quality Library

2000 Traverwood Drive

Ann Arbor, MI 48105

734-214-4311 & 214-4434

E-mail: Group_AALibrary@epa.gov