Ethanol plants pollute MORE than oil refineries: report

An ethanol plant on average produced 1,187 metric tons of carbon emissions per million gallons of fuel capacity in 2020. In contrast, the average oil refinery produced 533 metric tons of carbon emissions, according to Reuters.

In 2007, Congress mandated that biofuels such as corn-based ethanol be blended into gasoline with the goal of reducing greenhouse gas emissions.

While the Environmental Protection Agency (EPA) wrote regulations in line with Congress’ mandate that requires these plants use emissions-control processes that would result in lower-than-gasoline emissions. However, the agency exempted more than 95 percent of ethanol plants from the requirement through a grandfathered provision excluding plants built before or during the time the legislation passed.

These plants today reportedly produce more than 80 percent of the country’s ethanol.

The five biggest polluters, per gallon of fuel capacity, in 2020, the latest year of available data, were Archer-Daniels-Midland Co., Golden Triangle Energy, Central Indiana Ethanol, Green Plains Inc., and Marquis Energy, according to Reuters.

Green Plains, POET LLC, and Marquis said that despite the higher level of pollution coming from plant-level operations, overall, ethanol is cleaner than gasoline when factoring in considerations like emissions from driving vehicles.

The EPA has said that around one third of plants exempted from environmental standards meet the standard anyway, but overall, plants that were exempt produced around 40 percent more pollution per gallon of fuel capacity on average than plants that were required to abide by the regulations.

In response to a request for comment from Reuters, the EPA acknowledged that the fuel has a higher emissions production rate than that of gasoline, but stressed that ethanol is a cleaner fuel overall.

The agency also noted ethanol’s benefits on national security and rural economies. “Renewable fuels help diversify our nation’s energy supply, improving energy independence and security,” the agency said, adding that biofuels provide “good paying jobs and income to farming communities.”

Geoff Cooper, president of the Renewable Fuels Association, told Reuters that “Ethanol offers a significant and immediate carbon savings."

While biofuels researchers have noted that ethanol has the key environmental advantage over gasoline of burning cleaner in cars, they note concerns over emissions associated with the process of planting and harvesting the corn as well as the refining process.

Researchers have sought to track pollution through the fuel’s entire life cycle, with a growing majority of academics coming to the conclusion that overall, ethanol produces more carbon over its lifecycle than gasoline.

"A study published by the National Academy of Sciences in February, for example, estimated that ethanol produces 24% more carbon," Reuters reported.