Site items in: Emissions Testing

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

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.

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

Ammonia-fueled engines on the horizon
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Ammonia-fueled engines on the horizon

Geofrey Njovu March 11, 2025

With commercial deployment scheduled to start this June, both WinGD and MAN ES’s under-development ammonia fueled engines have reported promising results across performance, ammonia safety and emissions optimisation parameters. MAN ES and MITSUI have also commenced a commercial-scale prototype test of the MITSUI-MAN ES large-bore, low-speed, two-stroke ammonia engine in Tamano, Japan.

Ammonia Energy Conference 2024: Ammonia for Maritime Propulsion is full speed ahead!
Article

Ammonia Energy Conference 2024: Ammonia for Maritime Propulsion is full speed ahead!

Kevin Rouwenhorst November 26, 2024

During the recent 2024 Ammonia Energy Conference, we explored all the latest developments in ammonia-powered maritime propulsion. Engine makers reported strong progress ahead of deployment in 2026, the same year that large-scale vessels will hit the water. The panel explored early operations for the ammonia-powered A-Tug in Japan, as well as ancillary technology systems required for maritime ammonia engines, catalyst after-treatment systems for emission mitigation, and the potential for fuel additives to boost ammonia engine performance.