
If the U.S. government got energy bills in the mail like regular folks, the biggest would go to the Pentagon. Now, amid concerns about climate change and the volatile price of oil, the military has gotten serious about curbing its consumption of fossil fuels.
The U.S. Navy is leading the charge, pursuing a goal of getting 50 percent of all the fuel it needs for ships, jets and shore installations from alternative, renewable sources by 2020.
Today, the Navy pumps biofuels made with 10 percent beef fat into a dozen ships in what it calls its Great Green Fleet. At naval bases and other facilities on land, solar panels are producing clean kilowatts and LED lighting is slowing the clicks of energy meters. Navy bases and other shore installations are procuring 1.1 gigawatts of renewable energy, or half the power they need.
The Navy is conserving energy elsewhere, too, with navigators mapping routes that take advantage of winds and ocean currents to keep vessels at sea longer between fill-ups. It also teamed up with the shipping giant Maersk to test a biofuel made with algae.
Secretary of the Navy Ray Mabus is passionate about this. “We all benefit from a future where energy resources are more diverse, more available, more sustainable, more compatible with our environment,” he says.
The Great Green Fleet’s name is an homage to the famous Great White Fleet of battleships painted white that President Theodore Roosevelt dispatched on a goodwill trip around the globe more than a century ago. (Today’s fleet is regulation gray.)

Dennis McGinn, the assistant secretary who spearheads the Navy’s push to save energy and protect the environment, stresses that no retrofitting is required for a ship to run on the Green Fleet’s biofuel.
“You drop it in and don’t have to change a thing. It goes to the normal fuel tanks, pumps, filters and right on to ignition and combustion chambers,” says McGinn.
Partner nations in the recent Rim of the Pacific maritime exercise pumped alternative fuel into their ships’ tanks too. Energy conservation is not a hard sell to sailors and Marines, even grizzled veterans.
“They get it,” says McGinn, a former fighter pilot. “We’re more effective if we squeeze the most out of every barrel of oil and every kilowatt of electricity.”