(INS) CORN ETHANOL - WORSE FOR CLIMATE THAN GASOLINE?

Kelly Nieuwenhuis, farmer, with his grain auger loading corn into his semi-tractor trailer used to haul grain to ethanol plants in Primghar, Iowa on Sept. 23, 2019. Credit: Kathryn Gamble for The Washington Post via Getty Images

Ethanol made from corn grown across millions of acres of American farmland has become the country’s premier renewable fuel, touted as a low-carbon alternative to traditional gasoline and a key component of the country’s efforts to reduce greenhouse gas emissions.

But a new study, published this week, finds that corn-based ethanol may actually be worse for the climate than fossil-based gasoline, and has other environmental downsides.

“We thought and hoped it would be a climate solution and reduce and replace our reliance on gasoline,” said Tyler Lark, a researcher with the Nelson Institute for Environmental Studies at the University of Wisconsin, Madison, and lead author of the study. “It turns out to be no better for the climate than the gasoline it aims to replace and comes with all kinds of other impacts.”

The study, published in the Proceedings of the National Academy of Sciences, looks specifically at the effect of the Renewable Fuel Standard (RFS), which was first passed by Congress in 2005 and updated in 2007 (RFS2). The standard requires that blenders add billions of gallons of renewable fuel to the country’s transportation fuel supply every year, creating the world’s biggest biofuels program.

At the time, lawmakers and proponents hailed the standard as a major victory for the climate and part of an overall effort to reduce dependence on foreign oil.

But in the 15 years since, its promises have yet to be fulfilled, critics say, and a mounting pile of studies shows corn ethanol has not dampened demand for fossil fuels, as expected, but has instead forced the conversion of grasslands and forests into croplands, both domestically and internationally, releasing carbon in the process.

In the new study, Lark and his colleagues found that after the RFS took effect, farmers expanded corn production on nearly 7 million acres each year, causing the conversion of lands to cropland “such that the carbon intensity of corn ethanol produced under the RFS is no less than gasoline and likely at least 24% higher.” The policy, the study said, also resulted in increased fertilizer use, water pollution and habitat loss.

In a previous study, from 2019, Lark and his colleagues found that cropland expansion in the United States, mostly for corn and soybeans, has led to increased greenhouse gas emissions, but did not connect that expansion to the RFS. Inside Climate Change - link - Georgina Gustin - link - more like this (USA) - link - more like this - link