A new military submarine is using fuel cell technology to power its patrols of the deep.

Howaldtswerke-Deutsche Werft's (HDW) new "U 33" vessel is designed for use in the German Navy and is reported to be the most modern non-nuclear sub in the seas.

The Class 212 A submarine is part of a four-strong fleet of submarines that are destined to enter service at the start of 2006.

The vessels use an atmospheric air-independent propulsion system based on the hydrogen fuel cell, generating electricity from hydrogen and oxygen.

The power supply enables the submarine to stay below the surface for weeks without re-emerging, a marked improvement on the two-day capacity of conventional diesel-electric submarines.

The silent and non-heat generating mode of power supply also enhances the submarines' stealth and powers of evading detection.

HDW representative Walter Freitag told an audience at the christening of the new craft that the new technology offered a glimpse of the way forward for the military, according to Fuel Cell Today.

HDW has already received orders for seven of the export version Class 214 submarine, with the Greek Navy and the Korean Navy interested.