U.S. Navy Secretary Ray Mabus should stick to his job and get out of the biofuel business, says Sen. John McCain (R-Ariz.).

“You are the Secretary of the Navy, not the Secretary of Energy,” McCain says in a July 27 letter to Mabus, in which he also tells the secretary to avoid “politically driven demonstrations,” referring to a recent Pacific Rim exercise that, McCain says, apparently featured green-painted ships and aircraft as well as baseball hat souvenirs.

Mabus and other Navy officials have been touting the service’s investment in and use of biofuels, particularly during the exercise, in development of what the Navy calls its “Green Fleet.”

Navy officials see biofuels development as a matter of national security and say the service has little choice but to follow its current tack. McCain completely disagrees.

“Your decision to buy 450,000 gallons of biofuels at over $26 per gallon for a ‘demonstration’ using operations and maintenance funds provided by Congress to equip and train military personnel and operate and repair facilities was not authorized and is a terrible misplacement of priorities,” he says.

“That wasteful purchase, and the Navy’s commitment of $170 million to develop a commercial biofuels refinery, will result in a real cost to the readiness and safety of our sailors and Marines,” McCain says. “Neither of these activities were authorized by Congress and the use of the Defense Production Act without a comprehensive market survey or a compelling operational requirement represents an alarming departure from the traditional use of this authority.”

The committee, McCain notes, has proposed legislation that prohibits Mabus “from further sacrificing readiness or other critical needs for the sake of politically driven demonstrations and [codifies] the Navy’s position to purchase alternative fuels for operational use only at prices competitive with traditional fossil fuels.”

The legislation also “requires congressional authorization for a defense official to enter into a contract for the development of commercial refineries,” McCain says.

Neither provision, he says, restricts the department’s ability to continue to pursue cost-competitive options in response to the price volatility of petroleum-based fossil fuels.

Mabus and service officials have misconstrued the legislation, McCain says.

“Despite your assertions, the committee supports the investments by the Department of Defense in technologies and equipment that will save lives, cut costs, reduce fuel convoys, decrease fuel demand at our forward operating bases, and offer our warfighters greater endurance in austere conditions,” McCain says.

“The committee specifically authorized funding for continued research, testing and evaluation of new technologies, including certification of alternative fuels in order to expand the range of fuel options for the Navy,” McCain writes. “The committee believes these are the correct priorities for our military personnel in a tough fiscal environment.”

He says, “Your misrepresentation of the provisions threatens the credibility of the senior Navy leaders you have ordered to advocate on behalf of a speculative program that does not address the core needs of the Navy or the Marine Corps.”

McCain is experiencing pushback, however, from his own powerful colleagues. The Senate defense appropriations subcommittee July 31 approved legislation that continues funding for the Pentagon’s use of biofuels, Reuters reported, in a move pushing back against critics trying to limit outlays on programs such as the Navy’s “Great Green Fleet.”

Some biofuels funding was included in a $604 billion defense spending bill for fiscal 2013 passed by the subcommittee, the panel’s chairman, Democratic Senator Daniel Inouye, told reporters. “I think we do have funding for that,” Inouye said. He did not give the amount, and committee aides said they could not provide details before Thursday, when the defense spending bill goes to the full appropriations committee for a vote.

A committee summary of the defense bill said it included increases in the area of alternative energy but gave no details.