An A-10C Thunderbolt II flies over Florida's Gulf Coast on June 29, 2012, marking the second flight of an aircraft powered solely by an alcohol-derived jet fuel blend. Gevo Inc. recently sold the U.S. Air Force 11,000 gallons of fuel at $59 per gallon to complete certification testing to ensure it can be used in military jets. The company says it believes it can be cost-competitive with conventional fuel once it moves ahead with plans to build a commercial-scale production facility. REUTERS/Joely Santiago/U.S. Air Force/Handout

Full Story: U.S. Air Force tests biofuel at $59 per gallon