On 7 July last year, just before seven in the morning, a prototype aircraft – with pilot André Borschberg at the controls – took off from Payerne military airfield in France for a non-stop flight lasting 26 hours. What made the event significant was the fact that the aircraft, Solar Impulse HB-SIA, drew all its power from the Sun, using energy accumulated during the day to keep flying through the night. The FAI (Fédération Aéronautique Internationale) immediately awarded it three new world records in the Solar Powered Airplane class: absolute height (9 235 m), height gain (8 744 m) and duration (26 hours, 10 minutes, 19 seconds).

It doesn’t end there, of course. Bertrand Piccard, co-founder of the Solar Impulse project (with Borschberg), says he expects the next version, the HB-SIB, to circumnavigate the world non-stop within two years. The aircraft has a 64 m wingspan – about the same as that of an Airbus A340 – and weighs 1 600 kg. The 12 000 solar cells integrated into the wing supply four electric motors with renewable energy and charge the plane’s 400 kg lithium polymer batteries during the day.