The Secretary of the Navy called it a 'Historic day for America.'

Just 100 nautical miles north of Oahu, the Navy for the first time used biofuel blends for a carrier strike group on the U.S.S. Nimitz.

It's being called the Great Green Fleet.

With each takeoff of a jet, refueling of a ship, or tanker, the U.S. Navy wants to decrease its reliance on foreign oil as prices continue to rise.

"We can make big strides toward energy independence.  We can reduce our vulnerability that we currently have," said Secretary of the Navy Ray Mabus.

For the three day demonstration, the Navy spent $12 million for 450,000 gallons of biofuel costing more than $26 dollars a gallon and then blended it 50-50 with a petroleum based fuel, which costs between four to five dollars per gallon. 

"It's more but in last year and half, it's come down by at least half, and two years ago by a factor of 10 or 100 fold," said Vice Admiral Phil Cullom of the Navy. 

The U.S.S. Nimitz carrier is nuclear powered, but it can hold about 3.4 million gallons of gasoline to refuel ships and its aircraft.

"This is the first time biofuels has gotten to an operational environment and where it's not controlled.  It's the first time we've taken it to the fleet," said Rick Kamin, a Navy fuel tester.

While the Navy moves ahead on the more expensive biofuel, not everyone is on-board with the plan. Republicans in congress have criticized the Navy and the Obama administration of squandering precious dollars.