U36: Another Fuel Cell Submarine for the German Navy
16 May 2013, Fuel Cell Today
One of the most modern non-nuclear submarines in the world has been named during a ceremony at the shipyard of ThyssenKrupp Marine Systems GmbH, a company of ThyssenKrupp Industrial Solutions AG. This marks another important milestone in the ongoing shipbuilding programme for the German Navy: U36 is the second boat of the second batch of HDW Class 212A submarines destined for operation in the Navy. The German town of Plauen has assumed sponsorship for U36. The ultra-modern submarine was named by Silke Elsner, companion to the Mayor.
The contract to deliver a second batch of two HDW Class 212A submarines was signed on 22nd September 2006 in Koblenz with the German Office for Military Technology and Procurement/BWB (now the German Office for Equipment, Information Technology and Employment of the Bundeswehr/BAAINBW). The submarine building activities are taking place at the shipyards of ThyssenKrupp Marine Systems in Kiel and Emder Werft- und Dockbetriebe in Emden.
The two additional units will be largely identical to their sister ships from the first batch. They are also equipped with the HDW air-independent fuel cell propulsion system which has already given excellent results in operations with the boats of the first batch. The German Navy submarine U32 gave renewed proof of this in April 2013. On the way to participate in naval exercises in the USA the boat produced a new record for non-nuclear submarines with 18 days in submerged transit without snorkelling.
To meet changes in operational scenarios and to take constant technological advances into account, a number of modifications have been made in the second batch:
Integration of a communications system for Network Centric Warfare
Installation of an integrated Sonar and Command and Weapon Control System
Installation of a superficial lateral antenna sonar
Replacement of one periscope by an optronics mast
Installation of a hoistable mast with towable antenna-bearing buoy to enable communication from the deep submerged submarine
Integration of a lock system for Special Operation Forces
Tropicalisation to enable world-wide operations.
The Italian Navy has also decided in favour of a second batch of two HDW Class 212A submarines, which are being built under licence by the Italian shipyard Fincantieri. That means that the Italian Navy will soon also have four boats of this class available for operations.
U36 – Technical Data:
General boat data:
Length over all: approx. 57 m
Height including sail: approx. 11.5 m
Maximum hull diameter: approx. 7 m
Displacement: approx. 1,500 t
Pressure hull built of non-magnetic steel
SIEMENS Permasyn® motor
HDW fuel cell system [SIEMENS PEM fuel cell]
Low-noise skew-back propeller
The latest line of U212 and U214 Class non-nuclear submarines have been developed using a silent operating fuel cell plant that runs on nine 34-kilowatt Siemens polymer electrolyte membrane (PEM) hydrogen fuel cells. An air-independent fuel cell propulsion (AIP) system provides an extreme increase in underwater endurance, increased diving depth and overall efficiency.
Despite weighing over 1630 metric tons, the 212 can remain submerged for up to three weeks and stealthily discharge torpedoes with a water ram expulsion system to perform reconnaissance, interception and surveillance missions. Without needing to surface for such extended periods, the U212 can operate silently without emitting exhaust heat and thus reduce detection. Both models are also equipped with torpedo countermeasures including underwater effector jammers and offer minimized acoustic, thermal and magnetic signatures to provide a further degree of undetectability.
Fuel Cell AIP
Since the early days of submarine construction, increasing the submerged endurance has always been one of the most important objectives of engineering research and development activities. The dream of staying submerged for an almost unlimited period of time has become reality for non-nuclear submarines thanks to air-independent propulsion (AIP). HDW provides AIP systems both for direct integration into new submarine designs and as retrofit into already operational boats during modernisation.
Fuel cells are energy converters that transform chemical energy directly to electrical current without noise or combustion. In the HDW submarine application, they use hydrogen and liquid oxygen which are stored on board.
In the fuel cells, hydrogen and oxygen combine to produce water while giving off electricity (DC). This operating principle is the reversal of water electrolysis. The electrical energy is fed directly into the submarine’s main switchboard. The HDW fuel cell plant is designed as a special, silent energy converter and the extension of a conventional propulsion system. Its modular layout is just as simple as the principle itself. With its two highlight features of no exhaust gas production at all and extremely low dissipated heat, the HDW fuel cell system is the only AIP system that can be performed in a closed boat, irrespective of diving pressure and with no deteriorating influence on the submarine’s signature.
Meanwhile hardly any navy contemplating the acquisition of new non-nuclear submarines is prepared to do without the vast advantages of AIP. In addition, refit of 209 Class submarines with a fuel cell plug-in section is state-of-the-art and can be carried out within the scope of a regular major overhaul. The large number of submarines already operating or under construction with fuel cell propulsion systems is a clear indication of the extraordinary acceptance level of this technology by navies operating submarines throughout the world. Thanks to the advantages of low noise and low infrared signatures, high efficiency and low maintenance requirements, fuel cell plants are the ideal AIP solution for non-nuclear submarines.