Earlier this week a coalition represented by the Environmental Working Group and the Grocery Manufacturers Association made claims that ethanol causes more environmental harm than good, and requested a freeze by the federal government on the current levels of the Renewable Fuels Standard.

National Corn Growers Association President Bob Dickey says the groups are just trying to stir up fear and that ethanol is having a positive impact environmentally and economically. He says science has backed that up time and time again including in a study released by the University of Nebraska earlier this year that shows the many benefits of ethanol.

"Ethanol use today reduces greenhouse 59% compared to gasoline," Dickey says. "The production and use of 6.5 billion gallons of ethanol in 2007 replaced 228 million barrels of imported oil valued at $16 billion. Ethanol experts expect those numbers to grow and ethanol has also provided more than 260,000 jobs across the economy."

Dickey also cited a report released in January by the Keystone Alliance that farmers are producing more corn in a more sustainable way, which dispels claims that ethanol is hurting the environment and increasing food prices.

The coalition has been using a report released last week by the University of Minnesota to back their claims but after analyzing the report the Renewable Fuels Association says that these claims are based almost entirely upon insufficient and extremely uncertain analysis of potential land use changes.

"The finding that troubled us the most was that corn ethanol increases greenhouse gas emissions compared to gasoline based on the fact that large amounts of CRP land are going to be needed to satisfy increased demands for corn," said RFA Vice President of Research and Analysis Geoff Cooper. "We certainly don't agree with that assumption and believe that we are not going to need substantial new amounts of land. The increases in corn demand resulting from ethanol are going to be met through higher yield per acre."

If the authors' assumed land use change emissions are removed from the analysis, the paper suggests average corn ethanol reduces greenhouse gases by 30% compared to gasoline and advanced corn ethanol reduces GHGs by 46%.

"Our position has been and continues to be that the analysis around land use change is very much flawed and very much in its infancy," Cooper says. "So to assign emissions from potential land use changes to the ethanol lifecycle is disingenuous. Until we have better models and better methods for more accurately measuring land use change, we should not be rushing to judgment on what the emissions associated with land use change truly are."

Ultimately the University of Minnesota paper relies on debatable methodologies for which no consensus exists, fails to make appropriate comparisons between ethanol and gasoline, and fails to provide important details on key assumptions so Cooper says it should be seriously questioned and require careful scrutiny.