Ag Policy Blog

Oil Study: Ethanol Emits More Carbon Than Corn Plant Absorbs

Todd Neeley
By  Todd Neeley , DTN Staff Reporter
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A new study funded by the American Petroleum Institute concludes corn ethanol emits more carbon from tailpipes than the corn plant absorbs. (DTN file photo by Bryce Anderson)

In the cottage industry of paid-for studies and consultants, a new report claims the growth of the corn plant actually absorbs far less carbon from the atmosphere than biofuels emit at the tailpipe. That essentially throws a wrench in virtually all of conventional science that points to biofuels being far closer to carbon neutral than petroleum fuels.

University of Michigan Energy Institute professor and noted biofuels critic John DeCicco authored an American Petroleum Institute-funded study this week. It calls into question the generally accepted carbon-accounting methods that show biofuels are more carbon friendly than fossil fuels.

As he did in an earlier study for API, DeCicco concludes the likes of scientists at Oak Ridge National Laboratory, Duke University and the University of Minnesota to name a few, are flat wrong in their conclusion the entire biofuels lifecycle should include the growth of the corn plant – which has been found to be a real atmospheric carbon sucker-upper. DeCicco points to indirect land use change, or ILUC, as one reason why biofuels are greenhouse gas intensive.

ILUC is a largely disproven theory that expanded biofuels production in the United States leads farmers in other countries to respond by planting corn and other biofuels crops on marginal lands.

“The assumption that biofuels are inherently carbon neutral is a premise of most climate-related fuel policies promulgated to date, including measures such as the LCFS and RFS that evaluate GHG impacts using lifecycle modeling,” said the conclusion of the study in the journal Climatic Change. “However, this analysis found that the gains in CO2 uptake by feedstock were enough to offset biofuel-related biogenic CO2 emissions by only 37% over 2005–2013, showing that biofuel use fell well short of being carbon neutral even before considering process emissions.

“When this estimate of the real-world offset is considered together with values from the literature for displacement effects, the conclusion is that rising U.S. biofuel use has been associated with a net increase rather than a net decrease in CO2 emissions. This finding contrasts with those of LCA studies which indicate that even crop-based biofuels such as corn ethanol and soy biodiesel offer modest net GHG reductions. The global GHG impact of biofuel use remains highly uncertain. Nevertheless, the necessary condition for a biofuel to offer a CO2 mitigation benefit, namely, that the production of its feedstock must increase NEP, can be evaluated empirically. Doing so provides a bounding result that suggests a need for greater caution regarding the role of biofuels in climate mitigation.”

Officials with two major ethanol interest groups discounted the study.

Renewable Fuels Association President and Chief Executive Officer Bob Dinneen said in a statement Thursday, “This is the same study, same flawed methodology, and same fallacious result that Professor DeCicco has churned out multiple times in the past. He has been making these arguments for years, and for years they have been rejected by climate scientists, regulatory bodies and governments around the world, and reputable lifecycle analysis experts.

“As crazy as it sounds, Prof. DeCicco is essentially suggesting that plants ultimately used for bioenergy don’t absorb carbon dioxide from the atmosphere as they grow. In other words, he and his sponsors at the API are arguing that the scientific community’s centuries-old understanding of photosynthesis and plant biology is wrong.”

You can read a full RFA analysis here:…

Emily Skor, chief executive officer of Growth Energy, issued the following statement:

“Overwhelmingly, objective research demonstrates that biofuels are among the best tools we have to reduce greenhouse gas emissions and combat the effects of climate change. The latest attacks from John DeCicco and his sponsors in the oil industry reflect the same bogus arguments they have made for years, and policymakers aren’t going to be fooled. As the Department of Energy’s Argonne National Laboratory has demonstrated, ethanol is an earth-friendly biofuel that reduces greenhouse gas emissions by an average of 34% over its lifecycle, while advanced biofuels can reduce emissions by 100% or more over conventional gasoline.”

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Jay Mcginnis
8/31/2016 | 11:34 AM CDT
Study is authored by the American Petroleum Institute? Glad they care so much about CO2 emissions!