This study, by Life Cycle Associates, was designed to assess the impact on the carbon intensity, as measured by greenhouse gas emissions, of a corn ethanol pathway by taking into account the replacement of a portion of corn grain for feed with corn stover. The project received NCGA funding as part of a greater organisational effort to help find the answers farmers need in order to run the most efficient, environmentally friendly operations possible.

"It only makes sense that farmers place an incredible priority of caring for the environment," said NCGA Ethanol Committee Chair Chad Willis, a grower from Willmar, Minnesota. "Natural resources, such as healthy soil and clean air and water, enable us not only to make a living but also to continue what, for most, is a family tradition. Today's farmers take an active role in ensuring that we adopt farm practices that have been scientifically shown to raise the largest crop possible using the fewest resources, be they nutrients, land or water. NCGA supports our efforts by making the solid, scientific information necessary to act as good stewards is readily available."

This study is part of an environmental evaluation called life-cycle assessment, LCA. These processes can be evaluated from different starting and stopping points, for instance, from cradle-to-grave, cradle-to-gate, cradle-to-cradle, well-to-wheel.

By carefully selecting when the LCA evaluation process begins and ends, researchers can model the full GHG impact in a way that most accurately reflects the situation as it currently occurs and, if applicable, as it may occur if a variable were altered. By choosing to start at any certain point, be it at the very beginning, once it enters a gas tank or anywhere in between, the research can be tailored to answer specific questions important to achieving an accurate evaluation. Likewise, LCA analysis also allows for targeted use in that it can look at a variety of ends points, be it through fuel combustion or even recycling.

Life-cycle assessment studies provide quantitative data on what steps in the corn or ethanol production processes conserve or consume the most resources. By understanding which steps are the most sustainable, farmers and ethanol producers can make changes in their day-to-day activities and in their planning processes to best protect the environment. These choices are good for the pocketbook and for the environment as conserving resources often conserves costs too.