Argonne scientists slam study linking bioenergy, food scarcity 

Source: Amanda Peterka, E&E reporter • Posted: Wednesday, February 18, 2015

Biofuels scientists from Argonne National Laboratory have offered a scathing critique of a recent study that found the world cannot meet its future food needs and produce bioenergy at the same time.

In a set of comments posted yesterday, Argonne’s Michael Wang and Jennifer Dunn said the paper published by the World Resources Institute relied on faulty assumptions about bioenergy production, as well as ignored key studies that paint biofuels in a positive light.

“Aspiration and speculation were combined to form the authors’ opinions,” wrote Wang and Dunn, both of whom have previously studied greenhouse gas emissions of biofuels production.

According to the study published late last month, using land for bioenergy production takes away from land that’s needed to feed a burgeoning world population. The study also cast doubt on analyses that find greenhouse gas benefits from bioenergy, charging that those conclusions are the result of accounting errors.

Lead author Tim Searchinger, whose 2008 paper started the debate on the contribution of indirect land-use change emissions to biofuels’ carbon footprint, and co-author Ralph Heimlich concluded in their paper that land should not be used to grow plants for fuels and energy (Greenwire, Jan. 29).

Biofuel producers have slammed the study, charging that it rehashes old arguments about “food vs. fuel” and land-use change that have not held up to scrutiny (E&ETV, Feb. 17). In the face of criticism from the industry and the Argonne researchers, the authors of the paper have defended their conclusions.

In their comments yesterday, Wang and Dunn said the new research adopts a “narrow definition” of bioenergy production that assumes land used for bioenergy feedstocks cannot also be used for other agricultural purposes. The definition ignores some bioenergy inputs, such as soybean oil, that are produced as a byproduct of agricultural soybean production, Wang and Dunn said.

By assuming that one unit of bioenergy displaces one unit of food, Wang and Dunn wrote, the WRI analysis also ignored different human nutrition requirements and co-products that come out of the bioenergy process.

Bioenergy could, in some poorer regions of the world, enhance agriculture rather than compete against it, they argued.

“Bioenergy could enable farmers in poor regions to introduce agricultural technologies and improve infrastructure to increase farm productivity and thus to raise farmers’ income,” Wang and Dunn wrote. “Thus, bioenergy could help, not hinder,” sustainable agriculture production.

The WRI paper’s conclusion that cellulosic crops are not promising for biofuels production because they require land and are not very efficient at converting sunlight into energy also “contradicts recent studies that see an important role for cellulosic crops,” Wang and Dunn said.

They also questioned the paper’s conclusion that biofuels production does not result in greenhouse gas benefits, noting that a recent Argonne study — which was led by Wang — found that corn ethanol production results in about a 34 percent greenhouse gas reduction compared to a gasoline baseline.And they argued that bioenergy production has not expanded overall agricultural lands in the United States, even though it has led to more acres of land devoted to corn production.

Searchinger defended the research in an email today. He argued that Wang and Dunn’s claim that bioenergy production has not resulted in an expansion of cropland was false, pointing to the growth in global harvested land in the last decade.

“In the U.S., the main effect has been a shift in the crops we are producing, but that requires that the crops we are no longer producing as much be replaced abroad,” he said.

Searchinger added that the WRI paper used optimistic estimates of future bioenergy yields to come to its conclusions.

“The bottom line is that even more generous methods would not significantly change the bottom lines,” he said. “One bottom line is that very large percentages of the world’s crops or biomass are needed to produce quite small quantities of energy. Another bottom line is that with expected increases in demand for food and other products of land besides bioenergy, the dedication of land to bioenergy instead of these other needs, including forests, is a poor choice.”