Solar Impulse 2: the aircraft, which can remain aloft at night powered by batteries, demonstrates the possibilities of clean energy. photograph: new york times

Last year, two Swiss pilots became the first to fly across the US using the power of the sun. Now they are back with an even more ambitious plan, to (...)

André Borschberg, Co-founder and CEO and Bertrand Piccard, Initiator and Chairman (in the cockpit)  standing beside the cockpit of Solar Impulse 2, the single seater solar airplane with which they will attempt  the first round-the-world solar flight.  Photograph: Jean Revillard/

A solar-powered aircraft that will attempt to fly round the world next March was revealed in Switzerland this afternoon. It will fly day and ni(...)

Spectators view the Solar Impulse following  in Chantilly, Virginia. Photograph: Win McNamee/Getty Images

The final leg of the first trans-United States flight in a fully solar-powered aircraft began today. The plane, named Solar Impulse, took off from Was(...)