First ship-to-ship ammonia transfer

Conducted on 14 September 2024 at Western Anchorage WA19, 20 nautical miles off Port Dampier, Western Australia, the pilot involved the transfer of 2,700 tonnes of ammonia between two gas carriers – the Green Pioneer and Navigator Global – at rates up to 800 m³/hr.

The trial simulated future ammonia bunkering scenarios, providing crucial insights into technical, safety and regulatory considerations.

GCMD’s associated report, Path to Zero-Carbon Shipping: Insights from Ammonia Transfer Trial in the Pilbara includes comprehensive safety analyses spanning feasibility, risk, consequences and emergency response. It confirms that ammonia transfer at anchorage can be safely and practically achieved, provided appropriate safeguards are in place.

Key safety findings included a validated weather envelope of 20-knot winds and a 0.3m swell and CFD plume modelling that demonstrated limited risk to nearby vessels in worst-case ammonia release scenarios.

The study also identified and mitigated 23 medium-level risks using measures such as emergency release couplings, a dedicated firefighting tug and ammonia-specific emergency drills.

“In the past, bunkering guidelines took years to develop and were typically derived from operational experience,” said Professor Lynn Loo, chief executive of GCMD.

“In this case, guideline development is preceding commercial-scale operations, making it essential that these pilots are as rigorous and informative as possible.”