JAPAN – After our recent spate of electric truck and van articles news now of the latest in electric ship design. In 2004 Siemens filed a patent application in the US for their electric marine motor using superconductor technology. The plan is to utilise special high temperature conductors slung in pods under the hull using passing seawater as the essential coolant. The US Coastguard Research and Development Centre in Groton, Connecticut wrote a 2001 report describing a dynamic simulation model (DSM) of an electrically propelled ship with power provided by four 625 kW fuel cells. It concluded that a fuel cell-powered ship can achieve transient responses comparable to those of conventionally powered vessels.
Now a Japanese company have formulated plans to use electricity generated by battery power in their own “plug in and go” ferry. Small electric powered motors have been used in a marine environment for some time, from the bass fisherman’s car battery powered outboard upwards. Lately we have seen a combination of technologies, the so called “super eco ships” like the 2007 launched Nadeshiko Maru, a 70-metre long, 750 tonne coastal vessel incorporating diesel generators and contra-rotating propellers driven by electric motors to enable dramatic emission reductions.
Ferries have also used the technology reducing their CO2 emissions by 20% or more and NO2 by up to 40% whilst still retaining diesel drive. This latest ship, from the IHI Marine United Inc. however is a genuine all electrically driven vessel. Although the technology for the essential batteries still falls short the company fully expects a launch date of 2015 when they believe the situation will be resolved. With the current pace of battery development there are few who will doubt them.
Although at this time we have been unable to obtain more detailed vessel specifications the ship will apparently be 100 feet long and powered by batteries capable of 5000 kilowatt hours, about 300 times greater than those supplied in a normal electric car, giving the vessel a range of circa 75 nautical miles. The capacity will be for around 800 passengers but the initial cost may be up to 60% more than a conventionally powered ferry of similar size. This of course may be offset by the cost of fuel and maintenance.
The Handy Shipping Guide has of course run previous articles on the Japanese push to cleaner shipping using electricity in July and September and it should be remembered that nuclear powered vessels, of which there are many types, from icebreakers to submarines, are all powered by electricity.
