Ethanol isn’t as green as you might think, researchers say


A study found that the U.S. Renewable Fuel Standard has failed to meet greenhouse gas emission targets but increased corn prices by 30%. The Renewable Fuels Association called the report “a completely fictional and erroneous account of the environmental impacts of the Renewable Fuel Standard.

The carbon intensity of corn ethanol supported by the U.S.’s Renewable Fuel Standard (RFS) is likely at least 24% higher than gasoline, according to a peer-reviewed study from University of Wisconsin researchers.

Researchers determined that the production of corn-based ethanol under the RFS policy “has failed to meet the policy’s own greenhouse gas emissions targets and negatively affected water quality, the area of land used for conservation, and other ecosystem processes.” The RFS also pushed prices for corn up by 30% and other crops by 20%, they said.

The study aims to support policymakers as they determine the future of the RFS, which is among the world’s largest biofuel programs. The policy was first established in 2008 and is now under review by the Biden administration.

The study, Environmental outcomes of the US Renewable Fuel Standard, will be published in the March issue of Proceedings of the National Academy of Sciences of the United States of America. The work was supported by the U.S. Deptartment of Energy and the National Wildlife Federation, among others. The Bloomberg news service noted that the National Wildlife Federation is a vocal critic of the RFS.

‘Precarious’ conclusions, shouts trade group

The Renewable Fuels Association, which aims to expand demand for American-made biofuels, said the RFS is the “single most successful clean fuels policy in the U.S.” The group said ethanol has saved Americans money, reduced the country’s dependence on foreign fuels, and supported job growth.

The Renewable Fuels Association accused the researchers of “precariously” connecting a series of “worst-case scenarios.” The trade group’s president and CEO, Geoff Cooper, said that the RFA previously met with the study’s author and offered to collaborate on research but never heard back.

RFA released a line-by-line rebuttal of the University of Wisconsin study. The group references a study released in 2021 by authors linked to Harvard University and the Massachusetts Institute of Technology that found well-to-wheel greenhouse gas emissions of corn ethanol to be 40% lower than gasoline produced from crude oil.

The authors of Carbon intensity of corn ethanol in the United States attributed declining carbon intensity to improved farming practices, more efficient use of natural gas, and an increasing share of electric generation by ethanol refineries.

Source: Renewable Energy