Efforts to reduce carbon pollution using ethanol appear to have backfired. //

For over a decade, the US has blended ethanol with gasoline in an attempt to reduce the overall carbon pollution produced by fossil fuel-powered cars and trucks. But a new study says that the practice may not be achieving its goals. In fact, burning ethanol made from corn—the major source in the US—may be worse for the climate than just burning gasoline alone.

Corn drove demand for land and fertilizer far higher than previous assessments had estimated. Together, the additional land and fertilizer drove up ethanol’s carbon footprint to the point where the lifecycle greenhouse gas emissions—from seed to tank—were higher than that of gasoline. Some researchers predicted this might happen, but the new paper provides a comprehensive and retrospective look at the real-world results of the policy. //

Today, most gasoline sold in the US contains 10 percent ethanol, and about a third of the corn crop in the country is used to produce the fuel. While other sources would qualify, including ethanol derived from cellulose, “most RFS biofuel production has come from conventional corn ethanol,” the study’s authors pointed out. //

Expanding biofuels production would only add to the inflation, the researchers found. “Our estimates imply that for every billion gallons per year (BGY) expansion of ethanol demand, we would expect a 5.6% increase in corn prices; 1.6 and 0.4% increases in the areas of US corn and cropland, respectively; and attendant increases in GHG emissions, nutrient pollution, and soil erosion,” they wrote.