THE US military has been told to go green to cut costs after the Pentagon's annual fuel bill hit $US20 billion. The biggest energy-saving campaign by the Pentagon is forcing the armed services to look at alternative ways of powering aircrafts, ships and armoured vehicles. Algae, vegetable oil and even animal fat are coming to the rescue.
First in the line of the accountants' fire is the Air Force. Fighter aircraft use up 3,000 to 5,000 gallons of fuel on an average mission - at the current price of $2.18 a gallon. The Air Force's transport service, which ferries troops and cargo around the world, is the largest fuel-guzzling organisation on the planet.
The US Navy is planning to have a green carrier strike force by 2016, with every aircraft on board and all the escort ships being powered by a 50-50 mix of petrol and biofuel. The carriers are nuclear-powered "so that's already alternative", Admiral Philip Cullom, the head of the Navy's Task Force Energy, said.
In April the US Navy showed off a Green Hornet, a FA18 that has completed more than a dozen flights with half of the fuel tank containing an oil extracted from camelina, a member of the mustard family.
"When I spoke to the pilots they said they didn't know whether they had petroleum or biofuel ... it flew just the same," Admiral Cullom said. He plans to use the equivalent of eight million barrels of biofuel by 2020.
Jeff Braun, the director of the US Air Force alternative fuels certification office, said that on August 26 a C17 transport aircraft would attempt to fly on tallow (animal fat) fuel. "What's left over from the meat process is what we call yellow grease and you extract the oil from it," he said.
Alan Shaffer, the Pentagon's principal deputy director of defence research and engineering, said that an alternative oil source with potential was algae.
"The beauty with algae is that you can grow it anywhere and to grow it it needs to absorb carbon dioxide, so it's not only a very effective fuel, in theory it's also a carbon sink. That's a pretty good deal," he said. Mr Shaffer believes that with investment - the big airlines are interested - algae could take off.