Multi Maritime has, in close cooperation with the ferry operator Fjord1, launched a new green ferry concept. The ferry is a “plug-in” LNG hybrid, which incorporates several features to reduce the ferry’s environmental footprint. The concept has been developed as a part of Fjord1’s bid for operating the Lavik-Oppedal ferry link in western Norway.
The most eye catching feature is the two Flettner rotors which acts as sails. For the Lavik-Oppedal link, which has wind conditions suitable for the Flettner rotors, it has been calculated that the rotors contribute with minimum 12% of the ferry’s total energy consumption. The theoretical potential is significantly bigger.
A new hull form and propulsion concept has been developed. Normally on a double ended ferry both the forward and the aft propeller provides thrust. However the forward propeller is significantly less efficient than the aft. The new concept has thrusters with controllable pitch propellers which can be feathered, the forward propeller is then feathered and the aft propeller provides all thrust during transit. This will signicficantly increase the ferry’s propulsion efficiency. When docking and undocking both propellers may be used for optimal maneuverability.
Energy is provided by a highly efficient “lean burn” LNG driven engine. Part of the energy normally lost through the engine’s exhaust is recovered as electricity with an ORC heat recovery system. The engine is a part of a hybrid system which includes a battery bank. The battery bank may be sized to be charged with an arbritary amount of shore power. Electricity is distributed with a direct current (DC) distribution system, which reduces electrical losses compared to conventional systems.
The ferry’s capacity is 125 cars. It is 110 m long and 17 m wide.
[mappress] LNG World News Staff, July 04, 2012; Image: Multi Maritime