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Solar-Powered Catamaran Circumnavigates Earth


PlanetSolar catamaran

Tûranor PlanetSolar ©

This Friday, May 4, a vessel named Tûranor PlanetSolar will become the first totally solar-powered boat to circumnavigate the Earth. The broad, V-shape catamaran left Monaco on September 27, 2010, traveled west on a mostly equatorial route, and will return to the Monaco Yacht Club 584 days later. Now crossing the northern Mediterranean Sea from Corsica toward France, Tûranor will have covered 53,000 kilometers, roughly 28,600 nautical miles.

The carbon-fiber boat, 31 meters long and 15 meters wide, has a flat deck that is plastered with solar panels made by SunPower. Flaps can fold out to expose additional panels, creating a total solar area of 537 square meters (5,700 square feet). The panels, which average 18.8 percent efficiency—among the highest for commercial products—charge six banks of lithium-ion batteries that can generate up to 93.5 kilowatts of power (about 127 horsepower) and keep the catamaran going for three days with no sun. Top speed: 27.3 kilometers per hour (17 mph, 15 knots). The hull and outriggers are designed to minimize air and water resistance.


The 38,000 silicon solar cells power the boat’s motor, water systems, lights—everything except the small propane cooking stove. The six-man crew that crossed the Atlantic Ocean from Monaco to Miami was subsequently reduced to four people to demonstrate “that it is not necessary to have a large crew to operate these technologies,” says Raphaël Domjan, an independent Swiss engineer who founded the project, designed the boat and serves as its skipper. He and his team derived the name Tûranor, meaning “the power of the sun,” from J.R.R. Tolkien’s novel The Lord of the Rings.

Domjan, 39, posts a daily log on the ship’s multimedia Web site. His April 30 entry conveys a mix of excitement and melancholy: “I realize that all the details surrounding our adventure were actually the engine of our life for the last 18 months. It is an awkward feeling to think that in a few days, all these little things that had become our life will disappear forever. When we left Monaco in September 2010, I was looking forward to seeing my mountains again, but…today, I realized…that I will be missing this feeling I have when sailing off, once I will be back to my life on the ground.” His last post will be May 7, after a weekend of dockside festivities at the Monaco Yacht Club.

Armchair adventurers can follow the final two days of the crew’s journey through frequent updates on Facebook and Twitter; Tûranor is scheduled to arrive in Monaco on Friday at 2 p.m. local time (8 a.m. EDT). The Web site also has lots of data about the boat, profiles the scientific team and details the catamaran’s current position and the course it took around the world.

Less-smitten pragmatists may wonder why Domjan built the $24 million vessel and spent millions more dollars to conduct the 18-month journey. Domjan says the planet “deserves a better, brighter and less polluted future.” The project, he says, “will help to motivate engineers and scientists to develop innovative technologies, inspire people around the world and show that the impossible can become possible.”

Boat designer and project leader Raphaël Domjan (left) in the cockpit with Philippines vice president during passage in July 2011. ©

The views expressed are those of the author and are not necessarily those of Scientific American.

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