Ars Technica
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.
Proponents have long argued that corn-based ethanol bolsters farm incomes while providing a domestic source of renewable liquid fuel, while critics have said that its status as a carbon-reducing gasoline additive relies on questionable accounting. Based on the new study, both sides may be right.