M/S Viking Grace represents a new generation of ferries in which modern design, future concepts, a high level of service and consistent environmental thinking have permeated the entire project. The vessel that went into service on the Turku–Stockholm route in January 2013 is powered by Liquefied Natural Gas (LNG). It is unique among passenger vessels of this size in having LNG as a fuel alternative.
The LNG tanks are located outdoors on the rear deck. If the gas comes into contact with air it rises, since it is lighter. It is thus ventilated away. In cooled form, the pressure in the tank and piping system is very low. The pipes and double-mantled. This means that no gas is emitted in case of any leakage. In order to handle and transport the gas, it is cooled to -162 degrees Celsius. This transforms it into liquid form and reduces its volume by about 600 times.
Before combustion in the vessel’s engines, the LNG is heated and resumes gaseous form. LNG contains no sulphur.
Nitrogen emissions and particulates are reduced by 85 per cent and greenhouse gases by 15 per cent lower than with today’s fuel. By using LNG, the vessel will meet all emission standards established by the International Maritime Organization (IMO) that will go into effect in the near future.
The hull of the vessel is hydrodynamically optimised to minimise wave formation, which is particularly important when passing through an archipelago. The Viking Grace meets high standards of external noise elimination and is one of the greenest, quietest vessels in the world.
Waste heat from engines is used during port stays and LNG-based recycled cool air is used for ventilation.