The new MTU gas marine engine, the first from Rolls-Royce, has just completed 3,000 successful hours on the test bench at Friedrichshafen, Germany. As of 2018, Rolls-Royce will deliver the first certified series production gas engines for commercial vessels.

“We can now confirm that the engine meets both our requirements and those of our customers: its performance and its acceleration behaviour are similar to the excellent characteristics of a diesel engine. It is economical, reliable and clean,” said Dr. Ulrich Dohle, CEO of Rolls-Royce Power Systems AG.

Dr. Ulrich Dohle, CEO of Rolls-Royce Power Systems AG, said: “We are convinced that gas engines will become increasingly more important as supplements to our proven diesel engines for marine applications. Natural gas is an important fuel of the future. It will be available longer, it is cheaper to obtain in many regions of the world and has a better environmental footprint than heavy oil or diesel.” Future emission regulations will demand even more environmentally friendly propulsion systems than are currently available. In the case of the gas engine, health threatening substances in the exhaust gas have been reduced by 80-100 per cent compared with the diesel engine and greenhouse gases by up to 11 per cent. The new MTU gas engine will meet the IMO III emission standards in force since 2016 with no additional exhaust gas treatment required.

The 16-cylinder gas engine will cover a power range from 1,500 to 2,000 kW and will be based on MTU’s 16V 4000 M63 diesel engine for workboats. As of the end of 2017, the first series engines will be used to power a tug built by Damen Shipyards for Svitzer towage and salvage company. The two companies have entered into collaboration with MTU to jointly put the world‘s first tug powered by high-speed gas engines into service. It is to feature high performance in addition to reduced fuel costs and emissions. As a result of their dynamic acceleration behaviour, their low environmental impact, reliability and economy, the new MTU gas engines are ideally suited to tugboats, ferries, push boats and special purpose vessels such as research vessels.

The gas engine portfolio will initially be supplemented by an 8-cylinder engine, which is to be available on the market with a power range of 750 to 1,000 kW. As of 2019, this MTU gas engine is to provide the propulsion for a new Lake Constance ferry operated by the local public utility, Stadtwerke Konstanz, which will transit between the two Lake Constance towns of Constance and Meersburg. The new ferry will be one of the first in Europe to be powered by a high-speed pure-gas engine. It is to feature low emissions and improved economy while delivering high performance.

The new MTU gas engines will be equipped with a multipoint gas injection system, a dynamic motor management system and an advanced turbocharger. The multipoint gas injection system is designed to provide the engine’s dynamic acceleration behaviour, increased performance and reduced emissions. The competition concept ensures that the IMO III emission standards are met without the need for additional exhaust gas treatment. Controlled combustion ensures that fuel is used efficiently. The safety concept, which has been optimised for gas operation, includes double-walled gas supply lines, which means that no additional complex safety precautions are required in the engine room. On the test bench, it was possible to simulate real-life manoeuvres, which represented the dynamic acceleration behaviour of a diesel engine. The successfully completed 3,000 hours on the test bench demonstrate that the gas engine leaves nothing to be desired in terms of the customary reliability of a proven MTU Series 4000 diesel engine.

In its development of the new gas marine engine, MTU says it has benefited from the 30 years’ experience it has gained to date with stationary gas engines for power generation and the experience available within the Rolls-Royce Group, which has equipped ferries with medium-speed pure-gas propulsion systems for a decade.

By Jake Frith