The US Navy is going ahead with plans to convert much of its fleet to expensive biofuels despite opposition from members of Congress who say it is the wrong thing to do at a time when the US military faces nearly $500 billion in budget cuts.

Going green

The US Navy has a special message this year at the Rim of the Pacific exercises bringing together the navies of more than 20 nations off the Coast of Hawaii: It is time to turn green.

Joining the vessels is what the US Navy calls its Great Green Fleet of warships powered by fuel from renewable sources like algae, grass, and animal fat.

Over the last few months, the navy has been showcasing how biofuels can transform the military and eventually lead what Navy Secretary Ray Mabus hopes will be a transition away from energy sources in unstable parts of the world.

"The main reason we are moving toward alternative energy in navy marine corps is to make us better war fighters, is to reduce our vulnerability on imported fossil fuel," he stated. "(To) Make sure we have energy security and energy independence in the United States military, United States Navy."

Converting Navy's fleet, biofuels

The Obama administration wants half the Navy's fleet to convert to biofuels by 2020 and become a major force in the development of the biofuels market - much in the same way the military in the past has served as the developer of technologies such as GPS, computers, and cell phones.

"The Air Force is aiming to get half of its domestic jet fuel from alternative sources by 2016. And I'm directing the Navy and the Department of Energy and Agriculture to work with the private sector to create advanced biofuels that can power not just fighter jets, but also trucks and commercial airliners," said US President Barack Obama.

Cost effective

But with each gallon of biofuel costing $26 compared to less than $four that conventional fuel does, there is plenty of opposition from members of Congress who say it is a waste of money at a time when the Pentagon faces deep budget cuts.

"It's going to be more expensive to get these biofuels and it doesn't provide any operational improvement," said David Kreutzer who is energy analyst at the Heritage Foundation. "That is it's not denser energy. It has to be drop in fuel. We could be getting more fuel from domestic production much more cheaply instead of diverting resources in the navy towards biofuels, we could use them for equipment and material and personnel."

Efforts to convert the Navy are well under way. The USS Makin Island, the Navy's first hybrid amphibious assault ship has just completed its maiden voyage.

The green message has also been carried by the Navy's famous Blue Angels seen demonstrating the power of biofuels at a recent air show.

With money in short supply at the military, biofuels - for now - may be only for show.

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（来源：VOA 编辑：旭燕）