A cargo ship partially powered by a gigantic kite-like sail has completed a 12,000-mile roundtrip voyage across the Atlantic. Captain Lutz Heldt, who says the ship used around 20 percent less fuel thanks to kite power, says, “We can once again actually ‘sail’ with cargo ships, thus opening a new chapter in the history of commercial shipping.” Not to be outdone, a Japanese sailor has embarked on his own bon voyage: a 4,400-mile trip in a recycled-aluminum, wave-powered boat.

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