Using LNG as a fuel can offer a practical and economic solution for the ship operator. Operating a ship using a fuel in a gas state requires integration of the entire chain from ship side bunkering, storage, conditioning and delivery to the engine and its conversion into power. Within a period of a few weeks, builders of dual fuel engines Wärtsilä and MAN have published their own solutions to this question. Both systems allow the ship owner to deliver/complete dual fuel with LNG propulsion system from one manufacturer and have the reassurance that the entire system is compatible including bunkering and on board storage.

For more than 10 years the Viking cruise ferry MV Mariella has been successfully operating her four S.E.M.T. Pielstick 12VPC2.6.diesel engines with Humid Air Motor technology. This year the, Norwegian owned, purse seiner/trawler and factory vessel MV Kvannøy built in 2002, was converted to Humid Air Motor operation. NOx emissions were reduced by 61.3 per cent, a saving of 50 ton annually. The HAM system operates by saturating the incoming turbocharger charge air with sea water vapor before it enters the air box and then the combustion chambers. The result is a lower peak temperature in the combustion process thereby reducing NOx formation. The economic benefits of the change gives a theoretical payback time for the HAM retrofit of approx. 3 years.

Lloyd's Register is collaborating on a project to create a fleet of commercial coasters powered by a combination of sails and marine engine using biogas as a fuel. The project was instigated by B9 Shipping,. part of the B9 Energy Group. which operates and maintains 45 wind farms on the British Isles as well as developing tidal projects and biogas production. Estimates show that UK biomass power generators may need up to 45 million tonnes of biomass per year. B9 shipping wants to build up to 50 vessels to transport 30 million tonnes a year of wood chips, wood pellets and biocoal pellets from mainly Scandinavia by 2020. The 3,000 dwt coastal vessels are equipped with sails, with biogas powered Bergen engine(s) providing power when sail power is not available.