Trio of expertise to develop a world first tug

Those who follow the development of the towage industry, particularly the ship-handling sector, will know that exciting new developments and innovation are now an accepted part of the ongoing scene with designers able to offer a variety of options to those tasked with finding the best solution to any particular situation.

With tugs now often purpose built for individual ports and operations, the days of the market being dominated by the traditional single-screw tug are long gone. This latest innovation adds another option to the list, one that as well as developing the type of tug itself, also explores the increasing demand for eco-friendly solutions.

Damen Shipyards of the Netherlands, German engine manufacturer MTU Friedrichshafen (a subsidiary of Rolls-Royce Power Systems) and Danish towing service provider Svitzer have now embarked on this latest project to develop an eco-friendly tug, to be introduced in 2016.

The aim of the RSD© CNG tug is to develop a design that combines high power with lower fuel cost and a substantial reduction in emissions. At the heart of any ship-handling tug of course are the engines and here a new 16-cylinder pure gas engine is being developed by MTU, based on its proven workboat Series 4000 M63 diesel engine. It will be complemented with a multipoint gas injection system, a dynamic engine control and an optimised safety concept. Rolls-Royce Power Systems state that they are developing the new gas series in order to meet the extreme load profile of the tug with accelerations comparable to that of their diesel engines. The clean combustion process will ensure that compliance with IMO Tier 3 emission regulations is achieved without the need for additional exhaust gas after-treatment. The 2,000kW MTU gas engine will be characterised by high power density, combined with low fuel consumption.

Commenting on the reasons why Svitzer has decided to invest in such a unique vessel, CTO, Kristian Brauner, said: “As a major harbour towage operator an important consideration is also that this tug will realise a considerable reduction in fuel costs and obviously fuel is a major cost concern for all operators. And crucially, as a market leader it is important for us to stay innovative with regards to performing safe and eco-friendly operations and to reduce emissions. Through the years we have already developed one version of the ECOtug and with this in mind, the choice to develop the new CNG tug is a natural step towards remaining an eco-conscious towage company.”

By Peter Barker