MAN Energy’s Two-Stroke Ammonia Engine Fires 100% Load

MAN Energy Solutions has achieved a milestone at its Research Center Copenhagen facility, successfully testing and running its ME-LGIA ammonia-powered engine at full, 100% load for the first time. The company installed its proprietary selective catalytic reduction (SCR) system during full-load testing.

“We began full-scale testing in November 2024 and have since proceeded in a cautious and safety-first way,” said Ole Pyndt Hansen, Head of Two-Stroke Research & Development, MAN Energy Solutions. “We have now operated the engine on ammonia from 25–100% load, marking another step forward in the maritime energy transition. As such, we have now validated the ammonia fuel-injection system over the full load-curve with diesel-pilot amounts recorded according to our targets. The positive emission and performance characteristics from single-cylinder tests have been validated in full-scale engine operation.”

According to MAN Energy, its SCR system was operational during all test loads to treat exhaust gases, with supply and safety systems working appropriately. The next phase of testing will optimize performance and low-emissions capabilities, including injection, SCR systems, and control strategies.

Two-stroke ammonia test engine; image credit: MAN Energy Solutions

The ME-LGIA engine also offers power take-off (PTO) capability: “The ME-LGIA concept is based on the diesel-cycle combustion principle, which makes it eminently suitable for PTO,” said Christian Ludwig, Head of Global Sales & Promotion, Two-Stroke Business, MAN Energy Solutions. “Prior to this round of testing, we simulated PTO on the ammonia engine with very positive results and are happy to see this replicated in real life. We intend to support PTO on the ME-LGIA to the same degree as with the other diesel-cycle engines in our low-speed portfolio.”

AmmoniaMot 2

MAN Energy Solutions recently announced a significant development for its marine-based ammonia engine work: the AmmoniaMot 2 research project. With funding from the German government and extensive industry partnerships, the project’s aim is to develop a four-stroke, medium-speed, dual-fuel test engine that operates on ammonia for large-scale ship applications. This follows the design and testing of its first two-stroke ammonia engine.

Christian Kunkel, Head of Combustion Development and Four-Stroke R&D at MAN Energy, provided more details on the ammonia project: “An advantage for AmmoniaMot 2 is to have the two-stroke engine development in parallel to the project. Of course, we are using synergies between two-stroke and four-stroke in both directions with a deep technological exchange. As far as ammonia is concerned, we can copy and adapt some of the technical concepts and ideas from two-stroke engine development, mainly in the fields of safety concepts, compatibility of materials, and lube oil.”

MAN’s Ammonia News

In April 2024, K Line, NS United, and Itochu Corp. agreed to use a MAN Energy 60-bore ammonia engine in a bulk carrier new build. Imabari Shipbuilding will install an SCR-connected B&W 7S60ME-ammonia engine for the joint venture’s 200,000 dwt-class bulk carrier. MAN Energy’s ammonia-powered engine is currently under development in Denmark, and this deal represents one of the first projects for the product. MITSUI E&S will assemble the ammonia engine in Japan.