HD Hyundai Heavy Industries Engine & Machinery (HHI-EMD) has completed the type approval test (TAT) for its HiMSEN H22CDF-GA low-pressure (LP) gas ammonia engine at the Korean Register Green Ship Equipment Test and Certification Centre (KR TCC) in Gunsan, Korea.
The test was conducted in the presence of representatives from seven major classification societies: Korean Register (KR), ABS, Bureau Veritas (BV), DNV, ClassNK, Lloyd’s Register (LR), and RINA.
Ammonia is considered a promising zero-carbon fuel, as it emits no CO₂ during combustion. It is gaining increasing attention as a next-generation marine fuel to meet the IMO GHG reduction requirements and support the global transition toward carbon neutrality.
To proactively respond to this market transition, HHI-EMD has continued to advance its ammonia engine technologies. The company successfully completed TATs for the H22CDF-LA in 2024 and the H32CDF-LA in 2025, both featuring a high-pressure liquid ammonia fuel supply system based on the Diesel-cycle concept, demonstrating the performance and reliability of its ammonia engine technology.
The newly type-approved H22CDF-GA features a low-pressure gaseous ammonia fuel supply system. Compared with conventional high-pressure liquid ammonia engines, the H22CDF-GA simplifies the fuel supply system, thereby enhancing its competitiveness.
This TAT is regarded as particularly significant as it marks the first time a HiMSEN engine TAT has been conducted at KR TCC, Korean Register’s specialised test and certification facility, through technical cooperation between HHI-EMD and KR. HHI-EMD plans to further strengthen this cooperation with KR and continue expanding its capabilities in performance verification and certification for engines powered by ammonia and other environmentally friendly fuels.
With the successful completion of this TAT, HHI-EMD says it has established a comprehensive ammonia engine portfolio covering both high-pressure liquid ammonia engines based on the Diesel-cycle concept and low-pressure gaseous ammonia engines based on the Otto-cycle concept. HHI-EMD thus believes it is the first and only engine manufacturer to offer both types of ammonia engine technologies. With this differentiated portfolio, HHI-EMD will be able to provide optimised ammonia engine solutions tailored to diverse customer requirements, further strengthening its competitiveness in the market for environmentally friendly vessels.
Image: H22CDF-GA TAT (source: HHI-EMD)
