Ethanol fuel in the United States

The United States is the world's largest producer of ethanol fuel since 2005. The U.S. produced 13.2 billion U.S. liquid gallons (50.0 billion liters) of ethanol fuel in 2010, and together with Brazil, both countries accounted for 88% of the world's production in that year. Ethanol fuel is mainly used in the U.S. as an oxygenate to gasoline in the form of low-level blends up to 10 percent, and to a lesser extent, as E85 fuel for flex-fuel vehicles. Most ethanol fuel in the U.S. is produced using corn as feedstock.

The ethanol market share in the U.S. gasoline supply by volume grew from just over 1 percent in 2000 through less than 4 percent in 2006 to a peak of almost 10 percent in 2010, and domestic production capacity has increased fifteen times since 1990, from 900 million of gallons back then, through 1.63 billion in 2000, reaching 13.5 billion gallons in 2010. Most cars on the road today in the U.S. can run on blends of up to 10% ethanol, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Flexible-fuel cars, trucks, and minivans can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol (E85). By December 2010 there were nearly 9 million E85 flex-fuel vehicles on U.S. roads, however, regular use of E85 is low but common in the Midwest.

The Renewable Fuels Association reports 204 ethanol distilleries in operation and another 9 under construction or expansion as of December 2010, that when completed, will bring U.S. total installed capacity to 14.6 bg.[4][6] Ethanol production is likely to continue to soar over the next several years, since the Energy Independence and Security Act of 2007 requires 36 billion gallons of annual renewable fuel use by 2022, of which, ethanol from cellulosic feedstocks is mandated to be at 16 billion gallons a year. Production from corn ethanol is set to 15 billion gallons by 2015. Expanding ethanol industries provide jobs in plant construction, operations, and maintenance, mostly in rural communities. However, in early 2009 the industry was under financial stress due to the effects of the economic crisis of 2008 as motorists were driving less, gasoline prices had dropped sharply, there was excess production capacity, and less financing available.

Since most U.S. ethanol is produced from corn and the required electricity from many distilleries comes mainly from coal plants, there has been considerable debate about how sustainable corn-based bio-ethanol could be in replacing fossil fuels in vehicles. Controversy and concerns relate to the large amount of arable land required for crops and its impact on grain supply, direct and indirect land use change effects, as well as issues regarding its energy balance and carbon intensity considering the full life cycle of ethanol production. Recent developments with cellulosic ethanol production and commercialization may allay some of these concerns.