New ILUC modeling shows reduced effect

By Luke Geiver | June 10, 2010
For the National Corn Growers Association, a major element of indirect land use change is missing in the theory. "In 2010, the U.S. Department of Agriculture predicts our corn farmers will produce more than 300 million more bushels than just three years ago, and do so on nearly 5 million fewer acres," NCGA president Darrin Ihnen said. "International indirect land use change theory completely ignores or significantly downplays grower ingenuity and modern agronomy."

The comments from NCGA on the missing component in the ILUC theory debate came after Purdue University released a new, updated and revised version on ILUC. The study, "Land Use Changes and Consequent CO2 Emissions due to U.S. Corn Ethanol Production: A Comprehensive Analysis," is headed by Purdue agricultural economics professor Wallace E. Tyner, and completed in conjunction with the U.S. DOE's Argonne National Laboratory. Tyner, who also serves on the California Air Resources Board Expert Working Group, said the new Purdue report will be considered before the working group submits a report on the state's low carbon fuel standard (LCFS).

The new Purdue report shows a 10 percent lower GHG emission rate from corn ethanol production than previous reports, and has NCGA, the Renewable Fuels Association and Growth Energy calling either for the dismissal of ILUC theory, or immediate action to implement the new report in CARB's decision on LCFS. "The inclusion of model results in policy before the science has been fully established is not just a problem of rushing to judgment; in this case, it goes against the goal of reducing greenhouse gas emissions," Ihnen said. "By saddling corn-based ethanol with incorrect emissions, the California standard may actually increase its reliance on petroleum or foreign sources of ethanol."

The new version is based on three Global Trade Analysis Project simulations. The first simulations used economic data from 2001, the second used data from 2001-'06 and the third model used data from 2006-2015 including considerations for population growth and crop yield. Tyner said the third simulation represents the most accurate simulation, showing a number that corn ethanol creates 77.5 grams of CO2 emissions per megajoule, down from the 2009 Purdue report that indicated ethanol CO2 emissions equaled 86.3 grams. The 2010 version also calculates that in 2010 only 0.12 hectares of land is needed to produce 1000 gallons of ethanol, while 2009 numbers show 0.27 ha./1000 gallons were needed.

One of the main factors for the change in numbers stems partially from what NCGA was calling for. "We have better data on land productivity and on cropland pasture and CRP lands, and these data and associated parameters are now in the model," Tyner said. "We have improved the treatment of the livestock and livestock feed sectors. Similarily, these changes are reflected in the current version of the model." In past reports, marginal land conversion rates were only considered two-thirds as productive as prime land. The 2010 version however, shows that most areas, mainly in Brazil and almost 60 million acres in the U.S., are actually more productive than first thought.

Based on the new study, the new numbers, and a debate that is now even more closely associated with estimated considerations, NCGA has said that it is time to end the use of ILUC theory. "There are lots of reasons to support corn ethanol," Ihnen said. "It's a renewable domestic alternative to foreign oil that also provides significant greenhouse gas reduction compared to gasoline and creates and supports jobs in rural America." Ihnen's reaction to the new study: "Looking at today's headlines, it's time is now."

Although the fate of ILUC is yet to be determined, many are requesting the new study take the place of old data, and for policy decisions in the case of CARB, the removal of the ILUC theory all together. "Ethanol from corn can play a significant role in cleaning the air, creating U.S. jobs and securing our national and economic defense," said Tom Buis, CEO of Growth Energy. "These results prove that ILUC is a complicated and technical rule that should not determine the full implications for the ethanol industry until we have more detailed, long-term studies of the issue."

RFA president Bob Dinneen responded to the report by writing a letter to CARB chair Mary Nichols. "Time is of the essence," Dinneen wrote, "Adopting the Purdue ILUC value immediately would greatly enhance the ability of regulated parties to meet their greenhouse gas reductions obligations in the early years of the LCFS."

The Purdue report opened with the following statement: "We should from the outset acknowledge that land use change is a complicated process. It is driven by many factors and varies through time," the study said. "There are social as well as economic factors involved in the complicated process of evolving land use. The factors vary by culture, region, and economy. Obviously neither this analysis nor any analysis can capture all the factors involved in land use change."