US Navy shows 'great green fleet'

20 July 2012

The US Navy has demonstrated how ships and aircraft can be powered using a mixture of biofuel and regular petroleum-based fuels without modification during its 'Great Green Fleet' showcase in the Pacific.

Nuclear-powered aircraft carrier USS Nimitz is carrying more than 180,000 gallons of a 50-50 biofuel and regular fuel mix which is being used to power more than a dozen F/A-18 Super Hornet aircraft as well as two destroyers and a guided missile cruiser during the demonstration.

The biofuels can be used without having to modify the engines or fuel systems in either the jets or ships, but there have been criticisms that the US Department of Defence, which had its budget cut by $487bn over the next ten years and could face steeper cuts in January, can ill afford the fuels.

The 50-50 mix is said to have cost $15 a gallon, compared to the less than $4 a gallon paid for regular fuels. The US Navy spent $26 a gallon on the biofuels which make up half of the mixture.

Around 90 per cent of the biofuel is produced from waste cooking oil, with the remainder refined from algae.

"We've got to look for alternative fuels, we've got to look for alternative opportunities, and we've got to be efficient in energy," said America's Chief of Naval Operations Jonathan Greenert.

Last November, America's Military Advisory Board thinktank warned that the reliance on imported fossil fuels was the country's "Achilles Heel", and that the country needed to cut fossil fuel reliance by around 30 per cent in order to be able to withstand any closure of the Strait of Hormuz.