S-80 Class Submarine

The S-80 Class is a series of submarines of advanced technology, of the Spanish Navy that is currently under construction. Initially there will be four units, with a future expansion to six, two of which are already in production by the Spanish company Navantia factory in Cartagena. Their fundamental characteristic is a new propulsion system, designed for a high degree of autonomy under water. Its mission includes: projection of naval power on land, naval special warfare, surveillance, protection of naval forces, and deterrence. The first will enter service in the Spanish Navy in 2013 and the second in 2014. The construction of the third in the series began in 2009. It is expected that construction on the fourth will begin soon, as well as the commissioning of two additional units.

S-80 Class Submarine
Builders:	Navantia, Cartagena
Operators:	Spanish Navy
Preceded by:	Agosta class submarine
Built:	2005-2016
In commission:	2013 -
Building:	4
Planned:	4
General characteristics
Type:	Submarine with AIP
Displacement:	2,200 tonnes surfaced 2,426 tonnes submerged
Length:	71.05 m
Beam:	11.68 m
Draught:	6.02 m
Propulsion:	1 shaft diesel-AIP 3 Bio-ethanol engines (3 x 1,200 kW) 1 electric motor (3,500 kW), 1 AIP fuel cell unit (300 kW)
Speed:	12 knots surfaced 19 knots submerged
Complement:	32 (plus 8 special forces troops)
Armament:	6 - 533 mm torpedo tubes

S-80 Class Submarine Capabilities

The submarines of the S-80 class are designed to better complete their mission in threat scenarios. Their operational mobility will allow them to operate in remote areas, travelling discreetly at high speeds. Their air independent propulsion (AIP) system will ensure their ability to remain long periods of time in an area without being detected and their ability to operate in possible conflict zones.

Their capabilities include:

• A combat system for multiple target acquisition in different scenarios.
• The ability to transport personnel, including special operations forces.
• Low noise and magnetic signatures in order to minimize detection.
• Low radar and infrared signatures in order to minimize detection.

S-80 Propulsion

The AIP (air independent propulsion) implemented on the S-80 is completely different to French MESMA (Module Energie Sous-Marin Autonome) project.

The AIP system is based on a bioethanol-processor (provided by Hynergreen from Abengoa) consisting of a reaction chamber and several intermediate Coprox reactors, that will transform the BioEtOH in high purity hydrogen. The output feds a series of fuel cell from UTC Power company (which also supplies fuel cells for the Space Shuttle).

The Reformator is fed with bioethanol as fuel, and oxygen (stored as a liquid in a high pressure cryogenic tank), generating hydrogen and carbon dioxide as subproduct. This hydrogen and more oxygen is fed to fuel cells

The bioethanol-processor also produces a stream of highly concentrated carbon dioxide and other trace gases that are not burned completely during combustion. This gas flow is mixed with sea water in one or more ejector venturi scrubber and then through a new system called SECO₂ (or CO₂ Removal System), developed by Bionet, and whose purpose is to dissolve the "bubbles" of CO₂ in water to undetectable levels.

The oxygen and fuel flow rates are directly determined by the demand for power. The AIP power in the S-80 submarine is at least 300 kW.