By Geoff Fein
Aluminum multi-hull ships are more energy efficient than a steel monohull ship, an Austal USA official said yesterday at a naval energy conference.
"Multi-hulls by their nature are more propulsion efficient. The long slender hulls have much less resistance…and lighter is better, no matter what speed," Bill Pfister, vice president, external affairs for Austal USA, told attendees yesterday at the American Society of Naval Engineers Energy Futures Symposium in Arlington, Va.
"Fast ferry operators buy aluminum multi-hulls because they use less fuel than monohulls," he said.
Mobile, Ala., based Austal USA and General Dynamics [GD] Bath Iron Works are building the all-aluminum hull trimaran variant of the Littoral Combat Ship (LCS). Earlier this year, the team delivered the first of two planned LCS, the USS Independence (LCS-2), to the Navy. Work is now underway on the Coronado (LCS- 4).
Lockheed Martin [LMT] and Marinette Marine are building a semi-planing monohull variant of LCS. They delivered the USS Freedom (LCS-1) to the Navy in late 2008. The two companies are now building the Fort Worth at Marinette, Wis.
The Navy is set to select one of the two designs for its planned fleet of 55 LCS. Industry responses to the final request for proposals are due no later than March 29.
Pfister took the opportunity yesterday to tell the gathering there are significant advantages to the LCS-2 design.
"One of the principle benefits of the aluminum hull LCS is energy efficiency. The trimaran hull provides superior sea keeping and the multi-hull configuration provides additional space for stability management," he said. "But the number one reason we have designed a lightweight multi-hull ship is that it is a derivative of ships that commercial owners buy when they want to save fuel."
Pfister was one of four industry officials discussing acquisition policies. Earlier this year at the annual Surface Navy Association symposium, Navy Secretary Ray Mabus told attendees the Navy is going to hold industry contractually accountable for meeting energy targets and system efficiency requirements. And the service will use the overall energy efficiency and the energy footprint of a competing company as an additional factor when making acquisitions (Defense Daily, Jan. 19).
Pfister noted that while both variants of LCS achieve the same top speed, "somewhere north of 35 knots," but one of the variants needs 38 percent more power to do that, he added.
"That percentage will remain constant throughout the speed range," he added. "Basic energy efficiency differences are set by the weight and hull form at the outset."
Both variants of LCS use about 90,000 barrels of fuel a year, Pfister’s briefing slides showed. At the January ’10 Defense Energy Support Center price per gallon of $2.81, the total cost for fuel is $10.6 million per ship per year, he explained.
Pfister also reminded the attendees that the cost of LCS, under the congressionally mandated cost cap, is about $500 million.
He also pointed out that the Assured Delivery Price for fuel ranges from $10 to $100. "The cost of fuel is somewhere between five and 50 times greater than retail cost."
Displaying a chart that compared the life-cycle cost of the aluminum trimaran to the steel monohull, Pfister said that the Navy would save enough money to buy four additional LCS by taking the aluminum hull variant.
"The steel monohull uses one-third more fuel across the speed spectrum," Pfister said.
Now with both LCS teams writing their responses to the Navy’s RFP, Pfister said he was surprised to find little credit given toward energy savings in the RFP.
"My observation, despite both significant fuel reduction goals established by the Secretary and energy consideration being required for all acquisitions, in the downselect for a vessel that will comprise about 20 percent of the future Navy fleet there is neither evaluation credit for the energy savings feature nor lifecycle cost consideration for the current ship.
"My conclusion, this appears to be business as usual," Pfister added.
In a follow-on question and answer session, Pfister was asked why the Navy didn’t appear to be following the Secretary of Defense’s requirements for key performance parameters regarding the full burden cost of fuel for LCS.
"That was our question. The RFP…when it came out, we were a little bit surprised," he said. "I read from the back to the front to see the evaluation criteria…I was struck. It’s a best value criteria."
Pfister added that the Navy didn’t want a picture of the ship or anything about the characteristics.
"Read the RFP. There is nothing in there that leads you to a best value for the operator. It’s simply a ‘what’s best for me and a technical data package and some other stuff’…it’s cost," he said. "Why did the Navy do that, I don’t know."