December 3, 2009
MOL completes next-generation ferry concept
Mitsui O.S.K. Lines, Ltd. has completed the concept for its second in a series of next-generation vessels, which will be technically practical in the near future. The vessel is an environment-friendly ferry that can transport both cargo and passengers (ISHIN-II).
ISHIN stands for "Innovations in Sustainability backed by Historically proven, INtegrated technologies." The first ISHIN concept, a next-generation, environment-friendly car carrier, was announced in September.
The ISHIN-II ferry will use of LNG as its fuel when under way, resulting in cleaner exhaust gas and a large reduction in CO2 emissions.
Zero emissions are achieved while in port, and at berth by the use of shore power and rechargeable batteries.
To enhance passenger comfort, the design minimizes vibration and noise in passenger spaces.
ISHIN-II's main engine and power generation system will be fueled by liquefied natural gas (LNG), which generates over 20% less CO2 per thermal unit compared to the heavy fuel oil used by most conventional ferries.
Use of LNG also cuts emissions of NOx, SOx, and particulate matters (PM) such as soot, dust, and smoke, by about 90%, 98-100%, and 98% respectively.
Electricity will be supplied from an on-shore terminal to achieve zero emissions while in port. This is currently under study at Osaka Nanko Ferry Terminal.
Solar battery films will be installed on all cabin windows to reduce light entering the cabins and solar power, a renewable energy source, will supply electricity.
Excess energy generated while under way will be stored in high-capacity rechargeable lithium ion batteries. The batteries also supply part of the vessel's electricity needs in port, allowing it to achieve zero emissions while the vessel is in port or berthed.
ISHIN-II will have both a diesel engine and electric propulsion motor, and a contra-rotating propeller system. The propellers are aligned front to back and spin in opposite directions. The rear propeller absorbs the rotation energy of the front propeller. This greatly increases efficiency.
MOL-developed Propeller Boss Cap Fins (PBCF) have now been adopted on more than 1,700 vessels all over the world. The most advanced model will be installed on the ISHIN-II vessels.
Friction drag will be reduced by the use of air layer lubrication technology with recirculation. Minute bubbles of air are released from onboard the ship, creating an air layer that covers the ship's bottom. Collecting and recirculating the air will save even more energy.
ISHIN-II will also adopt the next-generation ultra-low friction ship bottom coating, in which smooth micro patterned indentations form on the painted surface, trapping water and reducing friction drag.
Electronic control optimizes fuel supply to the engine. SOx in exhaust gas will be virtually eliminated by using LNG as fuel. This allows for much more efficient retrieval and reuse of thermal energy from the exhaust gas, compared to conventional engines fueled by heavy fuel oil.
A drastically improved hull form below the surface will enhance fuel efficiency.
A smaller, more efficient engine will not only optimize propulsion efficiency, but will also minimize noise and vibration. The vessel will also provide passenger-friendly facilities and passenger-focused services such as simplified IT-based boarding procedures and smoother loading and offloading of vehicles thanks to an exclusive rampway for passenger cars.