The article contains a mistake. There are 42 gallons in a barrel of ethanol. The last paragraph quoted below should read 9.4 billion gallons, not barrels. The rest of the references to barrels is correct.
On a related note, another 4.3 billion gallons worth of capacity are under construction, so this story will repeat itself next year.
U.S. ethanol production rises 10 pct in May - EIA
NEW YORK, July 29 (Reuters) - U.S. ethanol production in May jumped 10 percent from April as the growing fleet of distilleries boosted output, a government report said.
U.S. ethanol output rose 1,675,000 barrels to 18,543,000 barrels in May, the latest month for which data was available, the Energy Information Administration said on Monday.
U.S. ethanol capacity has risen about 46 percent since July 2007 to more than 9.4 billion barrels per year as the government gave the industry generous incentives in an effort to reduce dependence on foreign oil.