A Real Innovation in Cruise Ferries
Again: Norwegian shipping companies taking the lead in propulsion innovation
MS Stavangerfjord is worldwide the first large cruise ferry powered exclusively by natural gas (using "single fuelled gas engines"). For this reason, this ship is the most environmentally friendly in their class with significant environmental benefits compared to ships powered by traditional heavy fuel oil. Emissions of nitrogen oxides (NOx) are reduced by 92 percent. Emissions of sulfur are eliminated completely, while particulate emissions are reduced by 98 percent. Last but not least, the technology the shipping company Fjord Line uses reduces emissions of greenhouse gases (CO2) by 23 percent. Stavangerfjord has been set in service in mid of July 2013 and runs, as expected, fully satisfactory for its owner.
The used “green motor technology from Rolls Royce” is well-proven on a number of ferries and ships used in the offshore industry. In addition to reducing emissions to a minimum, the ships will never spill oil during refueling, thereby eliminating the related pollution and risk of fire. The positive environmental impact is also reflected in cleaner engine rooms and no waste oil from the engines.
The innovative RoPax-Ferry Stavangerfjord
Four gas engines
The ship features four gas engines of type Rolls Royce Bergen B35:40V12PGas, each with twelve cylinders and delivering 5.400 kW (7.300 hp) each. They transfer the power via two shafts towards two controllable pitch propellers. Fjord Line's choice of the most advanced engine technology allows both ships to achieve the most profitable and environmentally friendly operation. In 2015, new stricter requirements for sulfur content in fuels will be introduced for ship traffic in Northern Europe. With gas engines, Fjord Line meets easily these requirements by a wide margin. When in ports, auxiliary engines are used, powered by diesel. These engines are equipped with powerful catalytic converters which reduce NOx emissions to almost the same level as the gas engines. The fuel (natural gas) is stored as LNG in two 293 m3 isolated tanks under the car decks.
The picture shows the double-walled gas-carrying pipes from the regasification system into the engine
Waste heat converted to electricity
To complement the use of clean fuel, a full-scale Aalborg waste and heat recovery system (WHR) has been installed on board, resulting in a reduction in natural gas use by about five percent. The system converts waste heat from the exhaust gases to steam-generated electricity. This covers the electricity needs for all cabins and public areas used by the ship's passengers and crew.
The length of the ship will result in the crossing between Norway and Denmark being much smoother than normal. In the North Sea, the average length of three waves together is 165 meters. The cruise ferry is 170 meters long so they will float on three waves instead of dipping down between the second and third wave. This will contribute to a much more comfortable trip. A modern and flexible interior design provides a capacity of 1500 passengers (1200 passenger during winter).
images: FjordLine, PPM News Service