MAN Energy Solutions announced that its MAN 51/60DF engine has passed the milestone of 10 million operational hours. The dual-fuel engine has proved popular with 310 engines currently in service—an increase of almost 100 units since 2022.

The 51/60DF engine, which can run on a wide variety of fuels including natural gas, biogas, bio-fuel, synthetic fuels, distillates and heavy fuel oil, has been in MAN Energy Solutions’ portfolio since 2009. It comes in various power classes from 6.3 to 20.7 MW and is serviced by MAN PrimeServ, MAN Energy Solutions’ after-sales division, on five continents.

This is a significant milestone that stands testimony to the character of this engine. The 51/60DF has become a fixture in shipping and power-plant operation and stands for absolute reliability—even in high ambient temperatures. Switching between the different fuels happens more or less at the touch of a button and is possible at any point between 0 and 100% load without any loss of power or frequency shift.

—Stefan Eefting, Head of MAN PrimeServ Germany

MAN Energy Solutions states that the 51/60DF is extremely reliable in both operation and maintenance. In addition to excellent availability of up to 98%, many of the engine’s core components show remarkably little wear even after extended operation, regardless of whether the engine has been running on heavy fuel oil or gas. Experience to date has also shown that the maintenance intervals achieved have significantly exceeded the expected, planned schedule of 36,000 hours.

MAN Energy Solutions is the only brand to supply all auxiliary system components to its engines. In addition to the MAN turbochargers integrated with MAN engines, customers furthermore receive MAN injection systems, as well as MAN control and automation systems from the one source. Accordingly, all individual systems are optimally matched to one other, meaning that a unique, customized service concept can be offered.

Fuel flexibility is a must for modern engines. The 51/60DF is already operating on heavy fuel oil, marine diesel and liquid biofuel, biogas, green Synthetic Gas (SNG) and is well proven in numerous installations around the world through its compliance with the ever tougher emission requirements of World Bank and IMO. In the coming years, it will also be capable of operation on other especially green synthetic fuels as methanol and by that contribute to the decarbonization of the energy and maritime sectors.

—Stefan Eefting