MAN Energy Solutions has successfully completed the Type Approval Test (TAT) of its latest dual-fuel engine, the MAN L35/44DF, marking a key milestone in its mission to deliver high-performance, future-ready marine power solutions.
The engine, designed for use as an auxiliary genset and in electric propulsion systems at constant speeds of 720 and 750 rpm respectively, underwent rigorous testing from April 7–11 at the STX Engine headquarters in Changwon, South Korea. The TAT was conducted in the presence of six international classification societies, underscoring the engine’s global relevance and compliance.
The trial covered both variants of the 35/44DF platform: the methane-capable 35/44DF CD and the methanol-ready 35/44CD. The L35/44DF CD represents a major upgrade over the earlier 35/44DF CR model, which was first launched in 2015. Key innovations include the Adaptive Combustion Control (ACC) system, which enables real-time monitoring and optimization of combustion parameters, enhancing fuel efficiency and operational performance.
“This engine is the result of a close, three-year collaboration with STX,” said Alexander Knafl, Senior Vice President at MAN Energy Solutions. “Its high power output, significant reduction in methane slip, and readiness for methanol and alternative fuels make it particularly well-suited for container ships and LNG carriers.”
Sephardim Koblenz, Vice President and Head of Licensing for Four-Stroke Marine & License at MAN, emphasized the engine’s cutting-edge features. “The 35/44DF CD is a future-proof concept, offering full digital connectivity, cybersecurity, high reliability, and excellent fuel economy,” he said. “In its development, we also focused on cost-effective manufacturing and easy localization.”
The engine draws on proven technology from MAN’s established 35/44DF CR and 32/44CR models, which have amassed millions of operational hours globally. The new Genset is engineered to reduce both capital expenditure (CAPEX) and operating costs (OPEX) for shipowners, while meeting the evolving demands of maritime decarbonization.
According to MAN Energy Solutions, the L35/44DF CD offers up to 85% lower methane slip compared to industry benchmarks and significantly cuts greenhouse gas emissions. These improvements position the engine as a critical solution for shipowners navigating stricter emissions regulations and pursuing long-term sustainability goals.
With its strong performance credentials and adaptability to emerging fuels, the MAN 35/44DF CD is set to play a key role in the future of low-emission marine propulsion.