The concept has been developed by Netherland-based SwitchH2 and Norway’s BW Offshore. [Image: DNV]

By Shardul Sharma

Netherland-based SwitchH2 and Norway’s BW Offshore have secured approval in principle (AiP) from DNV for the concept of a floating production unit to produce green ammonia, DNV said on March 10.

The NH3 FPSO will be built through the conversion of an existing very large crude carrier 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, DNV said. The offloading will be done through a floating hose, reeled from the aft ship to the shuttle ammonia carrier midship manifold. 

DNV’s vice president, business development for floating production, Conn Fagan, said: “The AiP covers all aspects of the integrated vessel concept including structural integrity, mooring, ammonia production, ammonia storage and cargo handling.”