The U.S. Navy angered Republicans by spending $26 a gallon for biofuels for this week's Great Green Fleet demonstration, but the Air Force received little attention when it paid twice as much per gallon to test synthetic jet fuel last month.
The Air Force bought 11,000 gallons of alcohol-to-jet fuel from Gevo Inc, a Colorado biofuels company, at $59 a gallon in a program aimed at proving that new alternative fuels can be used reliably in military aircraft - once, that is, their pricing is competitive with petroleum, which now costs $3.60 a gallon.
The cost of the Air Force demonstration - $639,000 - was far less eye-catching than the $12 million the Navy spent for biofuels to power a carrier strike group on alternative energy for a day.
But it was part of the same Pentagon push, which has escalated under the administration of President Barack Obama, to adopt green solutions to rising fuel costs.