Keith Matheny

Detroit Free Press

The multi-billion-dollar U.S. biofuels industry — promoted and expanded for more than a decade by the federal government — may be built on a false assumption, according to a University of Michigan study published Thursday that is sure to stir all sides in the contentious debate over the industry.

Despite their purported advantages, biofuels — created from crops such as corn or soybeans — cause more emissions of climate change-causing carbon dioxide than gasoline, according to the study from U-M Energy Institute research professor John DeCicco.

The study is the latest salvo in the expanding battle over whether biofuels, and the farmland increasingly devoted to them, are actually providing the environmental and climate benefits many expected.

Since the federal government mandated the use of renewable fuels in the U.S. fuel mix in 2005 and expanded that use in 2007, the share of the annual corn crop devoted to biofuels has more than tripled to 5.225 billion bushels, according to the U.S. Department of Agriculture. The amount of U.S-produced soybean oil devoted to the production of biodiesel fuel doubled over the past eight years, to more than 5 billion pounds.

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"This pulls the rug out from under over a decade’s worth of public policy in this area," DeCicco said.

But DeCicco's study is receiving energetic opposition from farming and renewable fuels advocates, who question his methodology and note that the research was funded by the American Petroleum Institute, which has a vested interest in seeing biofuels fail.

DeCicco's research challenges a premise at the foundation of the federal Renewable Fuel Standard: an assumption that biofuels are inherently carbon-neutral; that is, that the amount of carbon released into the atmosphere when biofuel is burned and an engine releases its exhaust is offset by the amount of carbon the corn or soybeans removed from the atmosphere during its growth cycle.

Researchers and policymakers look at life-cycle analyses, accounting for all of the emissions created in the supply chains for respective fuels. With gasoline, it takes into account not just tailpipe emissions, but carbon emissions during oil drilling, transportation, fuel refining and other parts of the process. For biofuel, that equation factored in refining and also farm activities and fertilizer use, DeCicco said — but not tailpipe emissions related to burning the biofuels, because of a presumed carbon dioxide offset from when the corn was grown.

"Carbon neutrality has really just been an assumption," he said. "To verify the extent to which that assumption is true, you really need to analyze what's going on on the farmland, where the biofuels are being grown. People haven't done that in the past — they felt like they didn't need to.

"I swallowed hard when I first, on a mathematical basis, uncovered the problem, which was about four years ago. A lot of interests have kind of congealed around this assumption."

Using U.S. Department of Agriculture cropland production data, determining the chemical composition of crops and accounting for all of the carbon from the plants, DeCicco created a "harvest carbon" factor. Over the past decade, as the consumption of corn ethanol and biodiesel more than tripled in the U.S., the increased carbon uptake by the crops only offset 37% of carbon dioxide emissions from biofuel combustion, DeCicco said.

"When it comes to the emissions that cause global warming, it turns out that biofuels are worse than gasoline," he said.

That notion is getting serious pushback from the Renewable Fuels Association, the leading trade organization for the ethanol industry.

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"This is the same study, same flawed methodology and same fallacious result that Professor DeCicco has churned out multiple times in the past," said Geoff Cooper, the association's senior vice president. "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 life-cycle analysis experts.

"Just like Professor DeCicco’s last study, this work was funded by the American Petroleum Institute, which obviously has a vested interest in obscuring and confusing accepted bioenergy carbon accounting practices. It’s flattering that API has taken such an interest in the climate benefits of biofuels; but the public would be better served if API spent its time and money examining and owning up to the very real — and very negative — climate impacts of petroleum."

Jim Zook, executive director of the Corn Marketing Program of Michigan and Michigan Corn Growers Association, stands by other research showing biofuel use significantly reduces greenhouse gas emissions when compared to gasoline. And biofuel production has other benefits, he said — it leaves a by-product that can be converted into a high-protein livestock feed.

"We are actually getting more products by going through the ethanol process, and being better stewards of our resources by doing that," Zook said.

Producing transportation fuels domestically also reduces the need to import petroleum from areas of the world that are often hostile to the U.S. and its interests, Zook added.

"It's just common sense — we don't deploy troops in a cornfield," he said.

DeCicco countered that all of his research is peer-reviewed, meaning other scientists in the field have, and will continue to, scrutinize it. As for the petroleum industry funding, DeCicco said that years ago, he reached out to other more environmentally oriented funding sources that he declined to specify, who weren't interested in funding his examination of life-cycle analysis.

"I come into this with a pretty deep scientific reputation as a straight shooter that just lets the numbers go where they will," he said. "The biofuels lobby and the people who developed these models kind of circled the wagons when questions started getting raised."

Andy McGlashen, spokesman for the nonprofit Michigan Environmental Council, offered his take on the U-M research.

"Our work to reduce the climate impacts of transportation is focused on improving public transit and supporting development and adoption of electric vehicles," he said. "We'll be following the discussions around this research, but at first glance the findings look like further reason to keep our focus on those priorities."

Emily Cassidy, a research analyst with the nonprofit Environmental Working Group, said DeCicco is looking into an area that "deserves a lot of scrutiny."

"There is mounting evidence that the Renewable Fuel Standard has been bad for the environment and the climate, and this paper is a new take on that," she said. "There are some fuels that could be beneficial to the climate, but those fuels would mostly be using crop waste and woody biomass that wouldn't be used for other things."

Michigan could better combat climate change by another method, DeCicco said.

"The name of the game is to speed up how much CO2 you remove from the air," he said. "The best way to begin removing more CO2 from the air is to grow more trees, and leave them. Prior to settlement, Michigan was heavily forested. A state like Michigan could do much more to balance out the tailpipe emissions of CO2 by reforesting than by repurposing the corn and soybeans grown in the state into biofuels. That is just a kind of shell game that's not working."

DeCicco's research was published online Thursday in the scientific journal Climatic Change.

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Contact Keith Matheny: 313-222-5021 or kmatheny@freepress.com. Follow him on Twitter @keithmatheny.