While we keep an eye on the journey of Solar Impulse 2, the solar-powered plane that's currently in the middle of its record-setting, around-the-world flight, it looks like it has a buddy in the water. Solar Voyager, an autonomous, solar-powered kayak, is currently making its way across the Atlantic Ocean.

The idea follows in the wake of the Klepper E-Kayak, but while the E-Kayak is an add-on kit for a human-powered vessel, the Solar Voyager is designed to be completely unmanned. It can reach a top speed of 3 mph (5 km/h) running off a 280-watt array of solar panels, stored in batteries for night-time travel, and connects to the Iridium satellite constellation to navigate to preprogrammed GPS waypoints.

The robo-boat itself is 18 feet (5.5 m) long and 2.5 feet (0.76 m) wide, with a hull made of aluminum. Due to that design, the boat tips the scales at around 550 lb (250 kg), which the project team acknowledge is a drawback in terms of drag and efficiency, but the trade-off was made for a sturdier, more stable vessel, with better resistance against mechanical shocks.

Prioritizing strength could make all the difference between success and failure in the open ocean, as the Solar Voyager makes its way across the Atlantic. It was launched from Gloucester, Massachusetts, on June 1, and is attempting to reach Lisbon, Portugal, a journey which is expected to take four months. Every 15 minutes during its travels, the vessel reports its location, as well as details like its speed, bearing, weather and power generated and consumed.

If it's successful, Solar Voyager will be the first autonomous boat to cross the Atlantic, as well as the first to cross any ocean using solar power alone – a title it could claim from the Seacharger, which was recalled six hours into its trip from California to Hawaii a couple of weeks ago.

You can follow Solar Voyager's progress on a map on the project website, or with regular updates on Twitter.

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