Dr.-Ing. Tobias Haack, Rolls-Royce Marine Deutschland GmbH, Hamburg
Several factors are attracting shipowners to specify gas-fuelled ships. Emission regulations are getting stricter with SOX and NOX emissions in the focus -even though it is uncertain when Tier III will come into effect. The question is how much in the way of additional off-engine exhaust treatment systems will be needed. European and Scandinavian Emission Control Areas (ECA) are now in place, while corresponding ECAs will soon cover the east and west coasts of North America and other parts of the world. Furthermore the recent implementation of the Energy efficiency design index (EEDI) by the IMO has a huge impact on future ship designs and is in many cases limiting the engine size and ship speed of diesel powered vessels. But the most important argument toward gas as a ship fuel are the unknowns about liquid fuels in future, particularly the price and the availability of ultra low sulphur fuel. Natural gas as a fuel is a way of circumventing many of the problems. The next few years are likely to see a rapid uptake and corresponding building out of infrastructure for coastal and short sea operations. Rolls-Royce has invested heavily in gas engine technology and is in a position to provide not only medium speed gas engines, but also the onboard LNG storage and gas supply system to the engines.