Achieving such goals will also help make corn-based ethanol more environmentally friendly, Vilsack noted.

The 186-page report gives a detailed analysis on overall greenhouse-gas emissions by U.S. agriculture. The report also relies heavily on the Environmental Protection Agency studies on ethanol, but challenges the EPA's analysis on "indirect land-use change," which EPA uses as the largest single emissions factor for corn-based ethanol. According to EPA, 40% of net emissions tied to corn ethanol come from indirect land-use change. USDA's report cites "a large body of new research and new data," making the case that EPA's analysis for indirect land-use change is "much higher than what actually has occurred." Still, Vilsack said the report was not meant to supplant EPA's analysis.

"It is not -- I think it is important for me to say -- it is not an addendum or an amendment or a modification to what the EPA does," Vilsack said. "EPA has its own process, so it is not intended to be an update to that report. This is our report. We think it adds to the debate, adds to the data and adds to the conversation about this industry."

Vilsack also added that the report has international implications as well, because the practices and strategies highlighted can encourage more demand for biofuels globally. "What we're seeing is a lot of these same practices, a lot of these efficiencies, being adopted in other parts of the world as well, which is also having an impact on this industry and its greenhouse-gas footprint," he said.

Bill Hohenstein, director of the USDA Climate Change Program Office, said the study looks at what has actually happened as ethanol production has increased and how farmers have responded to that. Further, efficiencies have been gained in ethanol plants and the co-generation of products and reliance on natural gas at those facilities. There also was an argument that to increase ethanol production would require bringing more acres into production.

"What we have seen instead is an increase and intensification of production on existing lands," Hohenstein said. "That means double-cropping, reducing fallow, reducing idle pasture, higher harvest rates. All of that is how farmers globally responded to this increase in demand."

The study looks at two views of the future: a continuation of current trends, which would achieve that 50% reduction, and a more ideal case, looking at the most efficient ethanol plants and universal adoption of soil-health practices and nutrient management plans. That idealistic outlook could push ethanol to a 76% reduction of greenhouse emissions compared to gasoline.

Vilsack said the report is not just for farmers, but also to explain to the rest of the world the impact of farmer practices in the countryside. "That should be reassuring to folks who are concerned about whether or not farmers understand their responsibility of being part of this effort to reduce greenhouse gases. This report encourages them to continue this process and even accelerate it, because if they do, the benefits are pretty significant."

Last year, USDA started working on studies to look at various aspects of the biofuels industry, such as examining the energy it takes to produce ethanol, as well as detailing the relationship between corn-based ethanol and greenhouse-gas emissions.

Corn production has changed with conservation, precision agriculture, nutrient management, technology and efficiency, Vilsack said. The ethanol industry itself has gotten more efficient with newer production plants as well.

"Certainly this an industry over a period of time that has evolved," Vilsack said. "Can anybody take a look at that and determine how we are doing on the greenhouse-gas scale?"

Vilsack added that he thinks the Obama administration, and USDA in particular, worked aggressively over the last eight years to champion ethanol production and keep the Renewable Fuel Standard moving forward.

"I think we've got the RFS on a solid track, I think we've invested in expanded infrastructure so that higher blend fuels can be more readily available, we've worked with promoting advanced biofuels, we've worked with creating new industries -- the marine and aviation biofuel industries in particular," Vilsack said. "So we've been engaged with this industry throughout the last eight years."

Chris Clayton can be reached at Chris.Clayton@dtn.com

Follow him on Twitter @ChrisClaytonDTN

(AG/BAS)

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