April 16th 2002

German Shipyard Touts New Fuel-Cell-Powered Subs

Source:New Technology Week

Howaldtswerke-Deutsche Werft AG (HDW), a shipyard based in Kiel on the Baltic Sea,
recently christened the U-31, a class 212A submarine slated to begin service in the German
Navy in March 2004. The U-31 is the first of four submarines of this class, which HDW has
touted as "the most modern non-nuclear submarine in the world."

HDW said the U-31 has an air-independent fuel cell plant, which produces electrical power
from oxygen and hydrogen without internal combustion. The plant could enable the new
submarines to cruise under water for weeks without surfacing, HDW said. In addition, it said
the fuel cell would boost stealthiness: unlike a conventional motor, it makes no noise and
produces no exhaust heat.

The emergence of the new technology, with these improvements in stealth and endurance,
could undercut two arguments the U.S. Navy has made against buying diesel subs to
complement its nuclear-powered boats. But some experts are skeptical about whether the
German propulsion plant is as much of an advance as the Germans say. Other experts say
that, regardless, U.S. submariners are opposed to switching to even new and improved
diesel power for U.S. attack subs.

Standard diesel-electric subs have a major disadvantage compared to nuclear subs: during
underwater operation, the batteries empty after two or three days, and the boats must
surface in order to recharge under diesel power.

Led by Adm. Hyman Rickover, the U.S. sub fleet started becoming all nuclear-powered in the
1950s. European shipyards have continued building diesel subs, but have met with only
limited success in their efforts to increase the underwater endurance of their boats.

Juergen Rohweder, a spokesman for HDW, said the U-31 closes the gap between the diesel
electric and the nuclear submarine: "This is a great advantage for the submarine crews of
course, because it's noiseless and it's cold," i.e., it leaves no heat signature.

The German navy has not made public the U-31's crew size. But some details about its
capabilities are available. According to Rohweder, the fuel-cell sub can loiter underwater for
some two to three weeks; it would feature torpedo tubes with a water-pressure expulsion
system.

The U-31 would not eliminate the need for diesel engines. On the surface, it would be driven
by a diesel-electric motor; submerged, it would run on the fuel cell.

The fuel cells HDW has on order would be fed by hydrogen and oxygen that would be stored
as methyl hydrate in large on-board cylinders.

"This is very safe, and means that you can get more hydrogen into the cylinder than the
volume of the cylinder itself," Rohweder said.

In the future, the developers of fuel cells are hoping to find better ways to source hydrogen,
something that could further improve the sub design.

Rohweder said HDW is testing "reformer technologies" to produce hydrogen on board ship,
for example from ethylene. But fuel cell researchers are also looking for efficient and
cost-effective ways to strip hydrogen from water, which could provide a potentially limitless
source of fuel.

The fuel cell has another selling point: It's emissions-free, producing cleaner exhaust than
even the most efficient internal-combustion engine.

That sells well in ecologically conscious Germany. Joking, Rohweder added: "I always tell the
Greens here, it's environmentally friendly. ... Who else has it?"

HDW is already eyeing the export market, saying it has follow-on orders from Greece, Italy
and South Korea for fuel-cell subs. But the company's recent announcement made no
mention of another possible client: Taiwan. The Taiwanese are seeking new submarines to
defend the Straits of Taiwan against a potential invasion from mainland China; President Bush
has obliged, saying he backs Taiwan's effort to procure new subs.

However, Rohweder said that, although his company's interested in selling fuel-cell subs to
as many customers as possible, including Taiwan, "The German government has a clear
attitude. They clearly said no to an export to Taiwan, and of course we'll stick to the rules.

"We have made an offer and we have been interested in the past to get this, but we never
were allowed to do so," Rohweder explained. "The (German) government says what we
have to do, so we have to stick to it."

Meanwhile, the Pentagon is preparing to move along a series of design proposals for diesel
subs to Taiwan. Following on a promise from the administration to help Taiwan acquire the
subs, the Navy is currently reviewing design options from contractors.

At a recent conference, Philip Dur, the president of Northrop Grumman's shipbuilding arm,
said his company was interested in the potential Taiwan sub orders. General Dynamics,
whose Electric Boat subsidiary builds nuclear subs for the Navy, is another possible
contender.

Navy Lt. Cdr. Jeff Davis, a Pentagon spokesman, said the Pentagon hasn't yet set a date for
when the Navy plans to deliver a list of options to Taiwan, and said he would not be able to
name whom the proposals are from.

"Once the proposals are reviewed, we'll take the package to Taiwan and present those
proposals," he said.

Navy: No alternatives

But there is still stiff resistance within the Navy to building diesel subs.

Norman Polmar, a naval expert, said the Navy's nuclear sub community is "violently- and I use
the word 'violently' advisedly- opposed" to U.S. shipyards building non-nuclear submarines,
even for foreign sales.

In the early 1980s, Polmar said, both Israel and South Korea sought diesel subs from the U.S.,
but senior admirals but the kibosh on it.

"That would have been a boon for American shipbuilding," he said.

Polmar said the advances in diesel sub technology raise the question of whether the Navy
should procure a small number of non-nuclear subs for research, anti-submarine warfare
training and special operations. The fuel cell, he said, offers significant advantages in terms
of endurance.

Asked he saw such subs being developed for the U.S. Navy, Polmar was not sanguine: "If
we ever get a strong leadership in the Navy that recognizes these capabilities, then yes, I
could see us having them. But the leadership of the nuclear submarine communities tends to
always beat these guys down before they get up to four stars."

On the other hand, another expert, Norman Friedman, a naval historian and strategist, said
investing in diesel subs is a bad idea. More important, he said, is preserving the U.S. nuclear
sub-building infrastructure.

"If you don't maintain it, you're out of business," he said.

And he was skeptical of HDW's claims about the fuel-cell sub, calling it the "same story as all
the other air-independent propulsion" efforts.

"In a fuel cell sub that the Germans have, the fuel cell is used for loitering for significant
periods at very low speed," Friedman explained. "It's not used for main power. You still have
to use your diesels and recharge your batteries and all the rest. If you have to move several
thousand miles, you're going to do it on diesels."

He also suggested that the diesel-electric subs were a poor match for the Navy's global
reach.

"Anybody who's located thousands of miles from prospective areas of conflict gets real
interested in nuclear subs as a way of getting there in a reasonable length of time," he said.
"As soon as you're not operating in your own waters, diesel subs and mixed-propulsion
subs get a whole lot less sexy."

Polmar, however, suggested that the United States could rely on allies in the Mediterranean
and the Pacific, for example, to provide forward bases for non-nuclear subs.

"I'd say there are some areas of the world that are perfect for the U.S. to operate
non-nuclear submarines," he said.