Study finds that U.S. ethanol production growth has not triggered indirect land use change
St. Louis, Missouri, USA
July 27, 2011
A study published in the July 2011 Biomass and Bioenergy Journal on indirect land use change (ILUC) due to biofuels production indicates that the real impact of U.S. biofuels production on ILUC domestically and internationally is negligible or nonexistent.
The study, "Indirect land use change for biofuels: Testing predictions and improving analytical methodologies" was coauthored by Drs. Seungdo Kim and Bruce E. Dale of Michigan State University. Click here for the article abstract.
"This is the first evidence-based evaluation of ILUC utilizing actual historic data, employing a "bottom-up", data-driven, statistical approach based on individual world regions' land use patterns and commodity grain imports," said Dr. Roger Conway, senior partner at Rosslyn Advisors LLC and former director of the United States Department of Agriculture's Office of Energy Policy and New Uses.
Very few previous studies have attempted to find empirical evidence for or against indirect land use change from the historical data. Most previous studies relied on global economic simulations.
"Unlike most other ILUC work this study relied on very few assumptions and did not attempt to quantify nor to predict ILUC effects," said Dale. "We searched for direct historical evidence for ILUC in relevant world areas rather than attempting to project or predict what course ILUC might take. Projecting forward can force scientists to make untestable assumptions."
One interpretation of no ILUC effects is that U.S. crop intensification absorbed and exceeded new ethanol production demand. It is also possible that the effects of biofuels production expansion on ILUC may simply be negligible. Past studies based on economic model assumptions often do not take into account new agricultural techniques that allow for greater crop yields on existing U.S. lands where biofuel corn is produced.
The new study used 1990 -- when the U.S. biofuels industry was very small -- as its baseline and then measured crop changes against that as U.S. ethanol production grew rapidly in subsequent years. In order to test the hypotheses that ILUC had occurred, the authors searched for actual land use change in 18 regions around the world where corn and/or soybeans are produced.
Had ILUC occurred, use of crop land and arable land would have increased while the area of natural ecosystem land would have declined. Further, grain shipments from the United States to the other regions would decline. Finally, cropland in other regions would positively correlate with changes in harvested areas for corn and soybeans in the United States.
Using historical data to investigate real ILUC effects, the study found no statistical evidence of the changes predicted by ILUC theory in any of the 18 world regions.
"Prior modeling studies that relied on many assumptions have led to inflated projections for indirect land use change," said Dr. Steffen Mueller of the Energy Resources Center at the University of Illinois at Chicago. "Some work has substituted other data, such as the price of corn, to project ILUC. Modeling is important, but all models need to be tested and verified. These findings show that there is no substitute for using actual historic data when investigating ILUC."
Because other studies based their projections on economic model assumptions rather than empirical land use data their predictions on the effects of ILUC due to increased U.S. ethanol production varied widely.
More news from: NCGA (National Corn Growers Association)
Published: July 28, 2011