WinGD early testing of its X-DF-A ammonia-fuelled engine

A 52-bore single-cylinder version of the engine is currently operating at the company’s Engine Research and Innovation Centre (ERIC) in Winterthur, with final validation scheduled ahead of the first engine deliveries in June 2025.

The single-cylinder testing phase enables rapid validation of the ammonia combustion system under engine conditions, while also allowing optimisation of emissions and performance. This stage follows earlier combustion tests, validation of critical systems on dedicated test rigs, and the receipt of multiple class approvals for the safety concept. A multi-cylinder engine test at WinGD’s Global Research Centre in Shanghai will soon validate the full-scale engine, turbocharger configuration, and control system in preparation for production.

Sebastian Hensel, vice president of research & development at WinGD (pictured), stated: “The single-cylinder X-DF-A concept is running well, with combustion efficiency, emissions, and pilot consumption within our range of expectations. This milestone is a testament to our uniquely rigorous approach to innovation and the fantastic work of our development team and partners.”

WinGD’s ammonia development programme began in 2019, progressing in 2022 to experiments using the company’s unique spray combustion chamber (SCC). This was followed by a detailed investigation of key engine components at ERIC’s Future Fuels Lab. According to Sotiris Topaloglou, Head of Testing and Validation, the SCC results were directly transferable to test engines, underscoring the value of the early testing phases. “As a result, we are in a strong position to make rapid progress through validation of our ammonia technology,” he said.

Prior to single-cylinder engine tests, the X-DF-A ammonia fuel injectors were trialled on test rigs to validate their functional and mechanical reliability. They were also tested on a multi-cylinder methanol engine at full load, providing an opportunity to verify the ammonia injection concept under challenging engine conditions and make necessary refinements.

The development of the X-DF-A platform integrates established diesel-cycle technology with innovative solutions for ammonia injection and combustion. These innovations aim to maximise efficiency while controlling and minimising emissions. The development also includes extensive work on fuel handling and safety concepts, addressing the unique challenges posed by ammonia as a fuel. The safety concept has already received approvals in principle from several class societies and has been developed in collaboration with fuel technology providers. WinGD is now working closely with shipyards and early adopters to ensure safe installation and operation.

WinGD has secured nearly 30 orders for X-DF-A engines across the bulk carrier, containership, tanker, and LPG/ammonia carrier segments. Initial deliveries will include engines for four LPG/ammonia carriers owned by Exmar LPG and ten bulk carriers operated by CMB.Tech.