Why is the promotion of ethanol-powered gasoline in the US driving up carbon emissions?

U.S. President Joe Biden has campaigned on an ambitious plan to tackle climate change through a “clean energy revolution,” including encouraging a phase-out of gas-powered cars in favor of electric vehicles. But one key aspect of Mr Biden’s agenda contradicted this: he vowed to “promote ethanol and the next generation of biofuels”, declaring that they were “critical to the future of rural America and the climate”. Biden also named Tom Vilsack, a longtime ethanol promoter, to run the Agriculture Department

President George W. Bush passed a bipartisan law establishing the Renewable Fuel Standard, which effectively led to a big increase in U.S. corn ethanol production. As a result, the share of the large corn crop in the United States devoted to fuel rose from 11 percent in 2004 to 30 percent in 2015 and has remained stable. Both Barack Obama and Donald Trump have joined the pro-ethanol chorus.

Today, corn ethanol has replaced about 10 percent of “climate-changing oil” at the pump, and the industry’s main lobby group, the American Coalition for Ethanoly, boasts that ethanol production “supports 360,000 jobs in rural communities.”

Although ethanol was once embraced by some environmentalists, corn is very inefficient at turning the sun into fuel. Mark Jacobson, a professor of civil and environmental engineering at Stanford University, points out that plants store only about 1 percent of the solar energy gained through photosynthesis. By comparison, solar panels are 20 percent efficient. So you can put solar panels on the same piece of land and get 20 times more energy, and that energy can power an electric car.

In short, maintaining ethanol production at current levels means supporting a technology that is extremely wasteful of energy. By replacing oil, ethanol makes conventional gasoline cheaper, which leads people to drive more and buy less fuel-efficient cars. Expert studies have found that the net effect of the Ethanol Renewable Fuel Standard is to increase greenhouse gas emissions from vehicles by about 22 million metric tons of carbon dioxide a year, equivalent to the emissions of nearly six coal-fired power plants.

But are 360,000 jobs in rural communities supported by the ethanol industry? According to a study by the economics department at Iowa State University, it’s more like an industry spin. That figure includes all corn growers and their employees in the calculation. But when ethanol took off in the early 2000s, corn was a crop with a huge surplus, and the ethanol boom was more about creating a market for that surplus than creating new jobs. In fact, the ethanol industry directly creates only about 47,000 jobs, a fraction of rural employment, even in corn-intensive states such as Iowa. Meanwhile, solar alone has created more jobs than oil, coal, and natural gas combined, according to the U.S. Department of Energy. With the rise of cheap electric cars and the expansion of renewable electricity, ethanol is yesterday’s fuel. It remains to be seen whether Biden’s Environmental Protection Agency will decide whether to maintain federal support for the current Renewable Fuel Standard, which expires in 2022.