An amazing hydrogen-powered round-the-world ocean voyage has just gotten underway, with the US$5.25-million Energy Observer setting sail from Paris. The French vessel, which is set to make 101 stopovers in 50 countries across the globe during its epic 6-year undertaking, runs on wind and solar power, plus hydrogen generated from seawater. The trip, which will self-sufficiently circumnavigate the globe with zero greenhouse gas emissions, has been described as the 'Solar Impulse of the Seas', in reference to the pioneering solar-powered aircraft that flew around the world in 2016. The Energy Observer runs on solar power harnessed from extensive panelling ... in addition to two large wind turbines at the rear of the 30.5-metre (100-foot) long catamaran. When it's night time or when there's no wind to spin the turbines, the vessel relies on its chief innovation: an electrolysis system that extracts hydrogen from sea water and stores it in an onboard tank. While it all sounds very high tech, the Energy Observer ... is actually a 34-year-old former racing vessel [modified] to now serve as a model for emissions-free transport. That new mission is also why the vessel is expected to take some six years to complete its worldwide tour. Unlike previous renewable-powered sea voyages around the world, the Energy Observer's crew is taking their time ... hoping that each stopover in ports throughout 50 countries along the way will help demonstrate that there's a viable alternative to using environment-destroying fossil fuels.