Next year should, if all goes well, see the first round-the-world flight by a plane that uses no fuel whatsoever.

Solar Impulse 2 is the new, beefed-up and redesigned version of the plane that crossed the United States from coast to coast last year. It has eight more metres of wingspan, and its Swiss makers say it will be able to fly non-stop for five days and nights.

“It’s a possibility to keep a pilot in the air for five to six days in a row. There is an auto-pilot, lots of reliability, cross-feeding batteries and motors, toilets on board. The pilot can lie down, take physical exercise, also rest a little bit. This airplane is the airplane of perpetual endurance. What we really want to demonstrate is how many incredible things we can make with renewable energies, with clean technologies,” said daredevil pilot and Solar Impulse Chairman Bertrand Piccard.

Solar Impulse 1 grabbed headlines around the world with its record-breaking feats in 2013 and its innovative technology may find a host of real-world applications once it has proved its reliability and brought costs down.