EPA Issues Notice of Data Availability
Concerning Renewable Fuels
Produced from Grain Sorghum Under
the RFS Program
The U.S. Environmental Protection Agency (EPA) is issuing a
Notice of Data Availability (NODA) to release its lifecycle green-
house gas (GHG) analysis of grain sorghum used as a feedstock to
produce ethanol under the Renewable Fuel Standard (RFS) program.
The release of the NODA provides the public an opportunity to
comment on EPA's analysis.
EPA's analysis shows that grain sorghum, when used to make ethanol
at facilities that use natural gas, will meet the lifecycle greenhouse
gas emissions reduction threshold of 20% required by the Energy
Independence and Security Act (EISA) of 2007 for conventional
renewable fuel. When grain sorghum is used to make ethanol at
facilities that use biogas digesters in combination with combined
heat and power technology, it will meet the lifecycle greenhouse
gas emissions reduction threshold of 50% required by EISA for
advanced renewable fuel.
Background
In the final RFS2 rule, published in March 2010, 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 which fuel pathways meet the GHG reduction thresholds for the four
renewable fuel categories specified in Clean Air Act (CAA) Section 211 (o), as
amended by the Energy Independence and Security Act of 2007 (EISA). The CAA
SEPA
United States
Environmental Protection
Agency
Office of Transportation and Air Quality
EPA-420-F-12-029
May 2012
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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 GHG emissions of the renewable fuel as compared to the lifecycle GHG emis-
sions 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 green-
house 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 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 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. This NODA presents our analysis of potential pathways for
ethanol produced from a grain sorghum feedstock.
Lifecycle Analysis
In order to calculate lifecycle GHG emissions for the NODA regarding grain sorghum biofuel
pathways, EPA utilized models developed for the final (RFS2) 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.
Pathway Determinations
EPA's analysis found that ethanol produced from grain sorghum have an estimated lifecycle
GHG emissions reduction of 32% when produced at dry mill ethanol facilities that use natural
gas, and 53% when produced at dry mill ethanol facilities that use biogas in combination with
combined heat and power technology, compared to the baseline gasoline fuel it would replace.
Therefore, grain sorghum ethanol produced at plants using natural gas meets the minimum 20%
GHG emissions reduction threshold for conventional biofuels, and grain sorghum ethanol
Clean Air Act Section 211(o)(l)
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produced at plants using biogas in combination with combined heat and power technology
meets the 50% GHG emissions reduction threshold for advanced biofuels as required by EISA,
Administrative Process
With this NODA, EPA is soliciting comments on our analysis of the pathways for ethanol
produced from grain sorghum. We will consider all relevant comments received and will inform
the public of any resulting revisions in our analyses. Public notification could be accomplished
in one of several formats, such as Federal Register notice, a rulemaking action or a guidance
document. The appropriate form of public notification will depend on the outcome of any
reanalysis we deem appropriate after consideration of public comments.
For More Information
For more information, please visit the RFS website at:
www.epa.gov/otaq/fuels/renewablefuels/index.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
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