Wouldn't it be great if boats ran on something that is both clean and plentiful at sea? Like waves for example. That's not so crazy, it seems: The latest offspring of the Mermaid family (see lower in this post for the whole family tree) is the Suntory Mermaid II, a wave-powered boat.
"This month, 69-year-old Japanese sailor Ken-ichi Horie will attempt to captain the world’s most advanced wave-powered boat 4,350 miles from Hawaii to Japan. If all goes as planned, he’ll set the first Guinness world record for the longest distance traveled by a wave-powered boat and, along the way, show off the greenest nautical propulsion system since the sail."
Here's how it works:
Two fins mounted side by side beneath the bow move up and down with the incoming waves and generate dolphin-like kicks that propel the boat forward. “Waves are a negative factor for a ship—they slow it down,” says Yutaka Terao, an engineering professor at Tokai University in Japan who designed the boat’s propulsion system. “But the Suntory can transform wave energy into propulsive power regardless of where the wave comes from.”
The Suntory won't exactly be a speed boat. With a max speed of five knots, it will be at least 2-3 times slower than regular diesel boats, but the goal of Horie is not to beat speed records, it is to demonstrate that wave propulsion can work in the real-world and - hopefully - generate interest in it for commercial cargo shipping.
With some improvement in the wave-propulsion technology and combining it with wind sailing (kites, maybe), we can hope that it will become competitive with fossil fuels.
A few other notable green aspects: The boat is made of recycled aluminum and will use solar power to generate electricity for onboard equipment. Best of luck in your voyages, Captain Horie!
Here is the link !
http://www.treehugger.com/files/2008/02/suntory-mermaid-ii-wave-powered-boat.php