May 23, 2012

MEMORANDUM

TO: 			Air Docket EPA-HQ-OAR-2011-0542

SUBJECT:	Supporting Documentation for the Notice of Data Availability
(NODA) Concerning Renewable Fuels Produced from Grain Sorghum Under the
Renewable Fuel Standard Program

	

This memorandum accompanies information related to EPA’s analysis of
lifecycle greenhouse gas (GHG) emissions from ethanol produced from
grain sorghum.  As explained in the preamble to the Notice of Data
Availability (NODA), our analysis utilizes several data sources and
models.  To facilitate public review, below is a brief description of
the informational materials which accompany this memorandum.

1.  Summary of Grain Sorghum Modeling Inputs and Assumptions

This memorandum provides information on the key inputs and assumptions
used in EPA’s lifecycle analysis of grain sorghum used as a feedstock
to produce ethanol.  Assumptions include crop yields, co-products,
processing emissions, and other important factors in our lifecycle
analysis.

2.  FASOM Results

A spreadsheet that contains domestic agricultural output from the FASOM
model for the “grain sorghum control case” and the “grain sorghum
300MG case.”

3.  FAPRI-CARD Grain Sorghum Control Case Results

A spreadsheet that contains the international agricultural results from
the FAPRI-CARD model for the “grain sorghum control case.”

4.  FAPRI-CARD Grain Sorghum 300MG Case Results

A spreadsheet that contains the international agricultural results from
the FAPRI-CARD model for the “grain sorghum 300MG case.”

5.  BSLAM Sorghum NODA

This Excel-based model is used to perform EPA’s stochastic analysis of
international land use change GHG emissions impacts induced by grain
sorghum ethanol.  The results from this model are input into the results
spreadsheet to calculate a 95% confidence range for lifecycle GHG
emissions.

6.  Sorghum Impact Calculations – 0% Wet DG

This spreadsheet calculates GHG emissions per unit of grain sorghum
ethanol.  The spreadsheet integrates results from of each stage of the
renewable fuel lifecycle (e.g., feedstock production, domestic and
international agricultural emissions, fuel transport and distribution). 
The only piece of the lifecycle analysis not calculated in this
spreadsheet is the emissions from international land use change.  The
results from the impact calculation spreadsheet are used in the results
spreadsheet, which compares the lifecycle GHG emissions of grain sorghum
ethanol with the 2005 petroleum baseline.  Results in this file assume
0% wet DG at the grain sorghum ethanol production process.  

7.  Sorghum Impact Calculations – 92% Wet DG

This spreadsheet calculates GHG emissions per unit of grain sorghum
ethanol.  The spreadsheet integrates results from of each stage of the
renewable fuel lifecycle (e.g., feedstock production, domestic and
international agricultural emissions, fuel transport and distribution). 
The only piece of the lifecycle analysis not calculated in this
spreadsheet is the emissions from international land use change.  The
results from the impact calculation spreadsheet are used in the results
spreadsheet, which compares the lifecycle GHG emissions of grain sorghum
ethanol with the 2005 petroleum baseline.  Results in this file assume
92% wet DG at the grain sorghum ethanol production process.  

8.  Sorghum Impact Calculations – 100% Wet DG

This spreadsheet calculates GHG emissions per unit of grain sorghum
ethanol.  The spreadsheet integrates results from of each stage of the
renewable fuel lifecycle (e.g., feedstock production, domestic and
international agricultural emissions, fuel transport and distribution). 
The only piece of the lifecycle analysis not calculated in this
spreadsheet is the emissions from international land use change.  The
results from the impact calculation spreadsheet are used in the results
spreadsheet, which compares the lifecycle GHG emissions of grain sorghum
ethanol with the 2005 petroleum baseline.  Results in this file assume
100% wet DG at the grain sorghum ethanol production process.  

9.  Sorghum International Agriculture Energy Emissions

This spreadsheet includes data about agricultural energy use in foreign
countries.  It is used to project lifecycle greenhouse gas (GHG)
emissions produced by additional crop production in foreign countries. 
Specifically emissions associated with:

Energy use per hectare of foreign crop production

10.  Sorghum International Agriculture NPK Pesticide

This spreadsheet includes data about agricultural fertilizer inputs in
foreign countries.  It is used to project lifecycle greenhouse gas (GHG)
emissions produced by additional crop production in foreign countries. 
Specifically emissions associated with:

Fertilizer, pesticide and herbicide use per hectare of foreign crop
production;

Nitrous oxide emissions per metric ton of foreign fertilizer
application;

Upstream emissions from fertilizer production are calculated separately
in the impact calculation spreadsheet.

11.  Sorghum International Rice Emissions

This spreadsheet includes data about rice methane emissions in foreign
countries.  It is used to project lifecycle greenhouse gas (GHG)
emissions produced by additional crop production in foreign countries. 
Specifically emissions associated with:

Methane emissions per hectare of foreign rice production

12.  Sorghum Results – 0% Wet DG

This spreadsheet integrates results from all stages of the fuel
lifecycle to calculate grain sorghum ethanol lifecycle GHG emissions. 
The lifecycle GHG reductions are calculated as percent emissions
reductions compared to a 2005 petroleum baseline, in this case gasoline.
 Results in this file assume 0% wet DG at the grain sorghum ethanol
production process.  

13.  Sorghum Results – 92% Wet DG

This spreadsheet integrates results from all stages of the fuel
lifecycle to calculate grain sorghum ethanol lifecycle GHG emissions. 
The lifecycle GHG reductions are calculated as percent emissions
reductions compared to a 2005 petroleum baseline, in this case gasoline.
 Results in this file assume 92% wet DG at the grain sorghum ethanol
production process.  

14.  Sorghum Results – 100% Wet DG

This spreadsheet integrates results from all stages of the fuel
lifecycle to calculate grain sorghum ethanol lifecycle GHG emissions. 
The lifecycle GHG reductions are calculated as percent emissions
reductions compared to a 2005 petroleum baseline, in this case gasoline.
 Results in this file assume 100% wet DG at the grain sorghum ethanol
production process.  

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