GHG Analysis of Dry Mill for Corn Ethanol Production under IRA

The Inflation Reduction Act (IRA) requires the calculation of greenhouse gas (GHG) emissions based on the GREET model for credit generation under Section 45Z. As specified in the Act: “The lifecycle greenhouse gas emissions of such fuel shall be based on the most recent determinations under the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model developed by Argonne National Laboratory, …”

Meeting the requirements of the Act is possible by grouping the GHG reductions options from dry mill ethanol plants into categories that are readily verified. This document reviews the GHG analysis for corn ethanol in GREET and identifies leading options to reduce GHG emissions and their corresponding effect on life cycle GHG emissions.

• Typical Dry Mill Ethanol Plant
• Carbon Capture and Sequestration
• Renewable Power
• Renewable Natural Gas
• Low Carbon Ammonia
• Manure Application
• Fertilizer Usage, including Bio-based Fertilizer
• No Till Farming
• Cover Crop

Each of these emission reduction options is represented in the GREET model and fuel producers could identify a combination of ethanol plant operation and corn farming parameters that are consistent with the GHG emission thresholds of the IRA to calculate their life cycle GHG emissions. Readily available GREET results for corn ethanol plant operation could be used by fuel producers to demonstrate GHG reductions under Section 45Z.