Site items in: Global

Emission performance of ammonia-fueled, four-stroke marine engines
Article

Emission performance of ammonia-fueled, four-stroke marine engines

Kevin Rouwenhorst June 03, 2025

We explore recent, full-scale, four-stroke engine testing results from IHI and Wärtsilä. Testing indicates N2O emissions can be almost fully eliminated with catalytic treatment, and significantly lower NOX emissions for engines running in ammonia mode, compared to running on diesel. While ammonia slip remains a key consideration due to the design of a four-stroke engine, catalytic treatment of the exhaust can eliminate even high concentrations, and release mitigation systems have already been designed and deployed to ensure safe operations.

Ammonia marine fuel cheapest option from late 2030s, dual-fuel vessels lowest-risk
Article

Ammonia marine fuel cheapest option from late 2030s, dual-fuel vessels lowest-risk

Julian Atchison May 30, 2025

Based on their analysis, UMAS and the University College of London conclude that scalable e-fuels have the highest potential to meet shipping’s new decarbonization targets, but that the next decade is critical to ensure supply chains are ready to supply these fuels. Ammonia-LNG dual-fuel vessels represent the lowest-risk, cheapest decarbonization option to the mid 2030s.

Emission performance of ammonia-fueled, two-stroke marine engines
Article

Emission performance of ammonia-fueled, two-stroke marine engines

Kevin Rouwenhorst May 06, 2025

We explore recent, full-scale, dual-fuel engine testing results from leading maritime vendors such as MAN Energy Solutions and WinGD. Testing indicates negligible emissions of the potent GHG N2O (which can be fully eliminated with catalytic treatment), and significantly lower NOX emissions for engines running in ammonia mode, compared to running on fuel oil or diesel. Overall, compliance with IMO Tier II and III emission limits is well within reach for the first generation of ammonia-fueled maritime engines.

MEPC 83: global shipping gets its first-ever emissions pricing mechanism
Article

MEPC 83: global shipping gets its first-ever emissions pricing mechanism

Julian Atchison April 23, 2025

The regulations send a clear signal to industry – business as usual operations will become significantly more expensive, and zero or near-zero (ZNZ) technologies and fuels represent one of the better opportunities to make deep emissions cuts. Following the historic vote at the IMO, we explore critical timelines for the new regulations, compliance thresholds, mechanisms for vessels to comply, and uncertainties that remain.

ZEMBA launches latest e-fuels tender
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ZEMBA launches latest e-fuels tender

Julian Atchison March 25, 2025

The Zero Emission Maritime Buyers Alliance has launched its second tender process for decarbonized fuels. Starting in 2027, the tender aims to cover multi-year cargo shipping demand equivalent to 1.5 million loaded, twenty-foot shipping containers transported from Shanghai to Los Angeles.

Setting the scene for ammonia maritime fuel: regulatory needs and timelines to decarbonize shipping
Article

Setting the scene for ammonia maritime fuel: regulatory needs and timelines to decarbonize shipping

Julian AtchisonKevin RouwenhorstAndrea Guati RojoTrevor Brown March 21, 2025

2025 is a critical year for the adoption of ammonia fuel in shipping. Here, we preview important upcoming meetings of the International Maritime Organization, what regulatory gaps are being filled by this work, potential candidates for decarbonization measures, and progress in engine development. All this sets the scene for incredible progress to be made in the coming years.