Long before solar cars were in the news, a giant white catamaran quietly proved that the sun can take you all the way around the planet. Tûranor PlanetSolar — “Tûranor” means “power of the sun” in Tolkien’s Elvish — left Monaco on 27 September 2010 and returned on 4 May 2012, after 584 days and more than 60,000 km at sea.
The carbon-fibre boat is 31 metres long and 15 metres wide. Almost its entire upper surface is a solar power plant: with its side flaps folded out, it carries 537 m² of solar panels at around 18.8% efficiency. They charge 648 lithium-ion battery modules (388 V, 2,910 Ah) — enough to keep the boat moving for about three days without any sun.
The electric motors deliver up to 93.5 kW. Average cruising speed was a relaxed 5 knots, while the top speed is about 15 knots (27 km/h) on sunny days in calm water. A diesel engine was installed for emergencies and insurance reasons — but it was never used during the entire voyage.
After its record circumnavigation the boat kept working for science and the environment. In 2015 it was handed over to the Race for Water Foundation and renamed Race for Water, sailing the oceans to study and raise awareness about plastic pollution.
Technical data
| Initiator | Raphaël Domjan, Swiss explorer |
|---|---|
| Design / yard | LOMOcean Marine / Knierim Yachtbau, Kiel; launched 31 March 2010 |
| Hull | Carbon-fibre catamaran, 31 × 15 m |
| Solar | 537 m² of panels, ~18.8% efficiency |
| Battery | 648 Li-ion modules, 388 V / 2,910 Ah, ~3 days of autonomy |
| Motors | Electric, up to 93.5 kW |
| Speed | ~5 kn average, ~15 kn (27 km/h) top |
| Record | First solar circumnavigation, 584 days, 60,000+ km (2010–2012) |
Photo: Dr. Karl-Heinz Hochhaus / Wikimedia Commons, CC BY 3.0
Sources: Scientific American · Electronic Design · Wikipedia: Tûranor PlanetSolar · CharterWorld