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Wave Powered Boat to Sail From Hawaii to Japan

Posted by samzenpus on from the clean-sailing-ahead dept.

CaroKann writes "In the middle of May 2008, Kenichi Horie, an adventurer known for such feats as paddling a pedal powered boat 4,660 miles from Hawaii to Okinawa in 1993, will be sailing a wave powered boat from Honolulu's Hawaii Yacht Club to the Kii Channel in Japan. The boat, a 3-ton catamaran named the Suntory Mermaid II, works by virtue of the fins located at the front of the boat. These fins "generate thrust force by moving up and down like the tails of dolphins and whales and absorbing the energy of the waves." The system can propel the boat no matter which direction the waves come from. Because the wave propulsion system absorbs the energy from the waves, a passenger on the boat will experience a smooth ride. With a top speed of about 5 knots, the journey is expected to take about 2 to 3 months."

4 of 152 comments (clear)

  1. Re:Wave powered boat by necro81 · · Score: 2, Informative
    From the project's website:

    Under normal use the sole power source is wave energy, but the boat can also use sails or an outboard motor when entering or leaving harbor, or in case of emergencies. While cruising, the outboard motor and sails will not be used.

  2. Re:Smuggler's dream by SirMeliot · · Score: 2, Informative

    This somewhat similar device should suit your coke smuggling requirements. http://news.bbc.co.uk/1/hi/technology/7234544.stm

  3. Re:Let's do the math by doooooosh · · Score: 2, Informative

    Well, for one, the according to this, the average wave height between Hawaii and Japan is closer to 10 feet, with a period of ~7.5 seconds. I doubt there's 10 feet of motion available in the fin of the boat, but it starts to account for the larger amount of energy available, and the higher speeds claimed. I'm far from a an expert in anything, really, so I'll leave it to someone else to make a better guess at the math.

  4. Re:Let's do the math by Deadstick · · Score: 4, Informative

    There's some confusion here about how the system works...it's not floats and beams.

    The effect that makes it possible is that the vertical motion of water under waves progressively decreases with increasing depth. The vanes are supported by two streamlined struts that stick down several feet below the boat. As the boat rises on the front side of a wave, the bottom of the strut assembly moves up at the same rate as the boat, but the water at that depth is not rising as fast. Therefore, the vanes attached to the struts are being dragged upward relative to the water around them.

    The vanes are hinged forward of center, so as they're dragged up they rotate to an upward slant until they hit a stop; then they act as a kind of propeller blade, generating a net forward force. As the boat goes down the backside of the wave, they rotate to a downward slant and again you get a forward force.

    I built a model of one of these as a kid...worked remarkably well.

    rj