MAN Energy Drives Naval, Commercial Marine Industry with 175D Engine

Throughout March and April 2025, MAN Energy Solutions’ 175D marine diesel-electric engine obtained interest from several European customers across the Netherlands, Poland, Portugal, and Norway. With high-speed operation, a lower emissions profile, and significant fuel efficiency, the 175D is an adaptable solution across naval, research, and carrier-vessel applications.

Dietmar Zutt, International Sales Manager at MAN Energy Solutions, offered additional technical details on the company’s marine engine, addressing its power capabilities, control system, noise-reducing mounting structure, and more, and the latest maritime propulsion trends.

175D diesel-electric engine; image credit: MAN Energy Solutions

About the 175D

Customers rely on the 175D for quick maneuverability, rapid acceleration, and longer cruising ranges, all enabled by numerous technologies within the engine. “Due to common-rail technology, fuel is injected with maximum pressure even when operating at low rpm,” Zutt said. “Its latest design allows a high compression ratio, leading to high combustion and peak pressures and enabling rapid fuel ignition at low loads. The MAN Turbo Charger combines high compressor efficiency with a super-wide compressor map.”

Zutt also said that extended cruising ranges are enabled by lower fuel consumption. The common-rail injection system produces high engine dynamics over the entire load range, thus cutting the specific fuel-oil consumption rate. The 175D shipset is also equipped with the latest edition of the MAN Safety Control System, ensuring high levels of cybersecurity for naval marine applications, specifically.

“[The 175D’s] double-resilient mounting reduces vibration and structure-borne noise,” Zutt said. “Its configuration comprises elastic mounts between the vessel foundation and generator set base frame, as well as between the engine, alternator, and base frame. Gensets with double-elastic mounting have an extra isolation layer between the vibrating engine and the vessel foundation.”

Due to engines containing several natural frequencies, mounting ensures that a customer’s operating frequency does not align with natural frequencies of the first, second, or third order. MAN offers three variations of the 175D engine in 12-, 16-, and 20-cylinder configuration:

• 175D-MEL: light duty
• 175D-MEM: medium duty
• 175D-MEV: variable speed

It features a 175-mm bore, runs from 1,500 – 2,000 rpm, and has power ratings between 1,440 and 4,400 kW.

According to Zutt, the global naval market is highly active with many projects underway, so MAN Energy Solutions anticipates further 175D deliveries and installations. These will mostly take place as diesel-mechanical or diesel-electric propulsion systems, with other design requirements dictating the shipset configuration. In terms of alternatively fueled propulsion engines, Zutt identified four main areas: fuel flexibility, operational reliability, cybersecurity, and integrated logistics design.

Recent Deliveries

In early March, MAN agreed to deliver six 12V175D high-speed, variable-speed generator sets to the CRIST S.A. Shipyard in Gdynia, Poland, which is building an offshore support vessel (OSV) for the DOF Group. The ‘Sea Dragon’ OSV was designed by MMC Ship Design & Marine Consulting and will support operations offshore Newfoundland, Canada, including gas crew changes, drilling support, field-safety standby, emergency towing, and ice management. The Sea Dragon is slated for delivery by Q1 2027.

The company also signed two contracts to deliver 175D engines for multiple Portuguese Navy newbuild vessels: a multi-purpose vessel (MPV) and an offshore patrol vessel (OPV). For the first delivery, Damen Shipyards Group ordered four 175D engines to build a 107-meter-long MPV, with primary mission roles such as oceanic research, search and rescue, emergency relief, maritime safety, and naval-support operations. For the other project, West Sea-Estaleiros Navais will install 12x175D engines on six under-construction, 83-meter OPVs.

MAN is also set to deliver two 16-cylinder 175D-MEM engines to the Netherlands’ Royal Niestern Sander Shipyard, which will construct a multi-purpose CO₂ carrier for Wagenborg Operator: the EasyMax 5. Each engine will generate 2,400 kW at 1,800 rpm, powering the vessel for offshore, substrate CO₂ storage. The EasyMax vessel features a 14,000-ton cargo capacity and will be chartered by INEOS Denmark. MAN will deliver the engines in 2025.