NH3 FPSO Concept: Floating 'Green' Ammonia Production gets DNV AIP

March 10, 2023

Artists impression of the NH3 FPSO concept - a floating ammonia production unit developed by SWITCH2 and BW Offshore. Image courtesy SwitchH2 BV/BW Offshore

An industrial-scale concept for a floating production unit to produce green ammonia has secured Approval in Principle (AiP) from DNV, and the project is now ready to start the Basic Design phase.

The NH3 FPSO concept is being developed by Netherlands-based SwitchH2 BV and Norway-based BW Offshore and will be built through conversion of an existing Very Large Crude Carrier (VLCC) or a dedicated newbuild vessel. Receiving power primarily from a wind farm, the unit will produce hydrogen by electrolysis of seawater and nitrogen through the use of an air separation unit, combining these in an ammonia synthesis unit.

The ammonia gas produced by the unit will be condensed, and the liquid ammonia will be stored in the hull in order to be subsequently offloaded to an ammonia carrier. The NH3 FPSO will be permanently moored but can be relocated as necessary through planned disconnect. The offloading will be done through a floating hose, reeled from the aft ship to the shuttle ammonia carrier midship manifold.