The Navy just launched its first carrier strike group powered partly by biofuel, a mix made from beef fat. This is part of its “Great Green Fleet” initiative, which aims to draw power from alternative energy and lessen military reliance on foreign oil. Turning to alternative energy will give the military options so it is no longer at the mercy of fluctuating oil prices and oil-producing nations that may not have U.S. interests in mind, Navy Secretary Ray Mabus told the AP.