Swiss marine power company WinGD has secured the first approval in principle (AiP) for two-stroke engines fueled with ammonia. Lloyd’s Register awarded the AiP to WinGD’s X‑DF‑A dual-fuel range (earlier post), giving shipowners the assurances they need to realize vessel designs using ammonia-fueled main engines for the first time.

Development of WinGD’s ammonia-fuelled engine series has been advanced with strong support from shipowners, shipyards and engine builders. The first engine to be developed, the 52-bore X52DF‑A, will be available for delivery from Q4 2024 and is applicable to a range of vessels including gas and bulk carriers.

WinGD was able to validate to Lloyd’s Register experts that the X52DF‑A concept is technically ready to satisfy future regulatory requirements with no major obstacles. As part of the AiP process, Lloyd’s Register considered the engine safety concept, risk assessments and preliminary engine and fuel supply system design, as well as confirming the compatibility of materials with ammonia fuel.

WinGD will extend the X‑DF‑A platform to a 72-bore variant in 2025 followed by other engine sizes in 2026 according to market needs, accommodating a wide range of vessel types from small tankers and car carriers to very large tankers.

The WinGD X-DF-A is a dual-fuel engine which injects ammonia into the engine. The engines operate according to the Diesel principle in both diesel and ammonia modes, have the same rating field as WinGD’s existing Diesel engines and will be available with the same cylinder configurations.