Poster nuclear reactor k15 Le Triomphant SSBN

The K15 is a 150 MW pressurized water nuclear reactor designed by TechnicAtome in the 1980s to equip the Le Triomphant class nuclear submarines and the Charles de Gaulle nuclear aircraft carrier. An evolution of the K48 used on the Rubis class, it incorporates digital control and aims for optimal acoustic discretion. Its successor, the K22, is developed for the new generation aircraft carrier.

Designed at the CEA center in Cadarache, the K15 is based on a nuclear boiler derived from the K48 and was tested on a land-based prototype, the new generation reactor (RNG), active since 1989. The CEA's Military Applications Directorate (DAM) manages the design, maintenance and fuel supply, while TechnicAtome is responsible for construction and maintenance.

The land-based test reactor (RES), in service since 2018, is a modified version of the K15. This reactor uses plate fuel elements, a steam generator placed above the core, and excludes boric acid to limit effluents.

The K15 powers the propulsion systems of submarines and ships: either by a steam turbine connected directly to the propeller (turbo-mechanical propulsion), or via an electric generator (turbo-electric propulsion). It also provides electricity, fresh water and steam for various equipment.

Compact, it fits into a 12 m diameter hull with a 3 x 5 m tank. Very quiet, it is adapted to the requirements of nuclear submarines.

Two K15 reactors equip the Charles de Gaulle aircraft carrier, whose maintenance is entrusted to Naval Group. For the Suffren class, the K15 is a version derived from the Le Triomphant class SNLE reactors.