At 26 MW, MAN Diesel & Turbo has launched what it describes as the “most powerful four-stroke engine in the market”, the MAN 20V45/60 (pictured).

“The 20V45/60 expands the current performance range of MAN’s 4x family of diesel engines by more than 4 MW, while offering a best-in-class fuel efficiency of more than 50%”, said Wayne Jones, chief sales officer of MAN D&T. “We have listened closely to our customers to get a better understanding of their needs. Accordingly, we knew exactly where we wanted to go in engineering the next generation…We were aiming for a game-changing level in power density and efficiency, and we accomplished that mission.”

“Next to a frontloading approach, using thermodynamic engine process calculations, we used computational fluid dynamics to simulate and optimise the combustion process. Also, finite element analysis was used to optimise the engine’s mechanical strength and vibration behaviour. We then put the power unit to the test on the world’s largest four-stroke, single-cylinder test bed and started the experimental optimisation and validation phase”, said Dr Gunnar Stiesch, head of engineering, engines, MAN D&T.

The new engine employs two-stage turbocharging, with a low-pressure and a high-pressure turbocharger arranged in series. “We are the only company in the market that develops both engine and turbochargers”, noted Stiesch. This “allows us to truly tailor-design this engine for optimised two-stage turbocharging and to unleash its full potential. Operators thus profit from maximised peak pressure and optimal utilisation of the Miller Cycle.”

“The two-stage turbocharging prevents derating even at 2500 meters above sea level and the engine shows no decrease in output even in ambient temperatures of up to 53° Celsius”, said Alexander Stöckler, global head of sales, power plant business, MAN D&T.

The initial offering is for operation on fuel oil, in, for example, remote locations and on islands, where gas is not available. A version with integrated SCR is under preparation and will further reduce NOx emissions by up to 80%. Gas and dual-fuel versions of the engine are also currently in preparation.

The worldwide rise of decentralised power generation and renewables has significantly changed the capability profile that fossil fired power plants need to match, MAN observes. Consequently, the new 45/60 is designed to be suited to baseload as well as peak-shaving. “State-of-the-art plants need to be able to master repeated and rapid startups and the ability for load- following operation. The 45/60 reaches full load in a short time, effortlessly handles load reversals, and achieves high fuel-efficiency even when operated in partial load.”

More cylinder configurations will be added to the 45/60 engine family in the future.