Solar Impulse is a Swiss long-range experimental solar-powered aircraft project, and also the name of the project's two operational aircraft. The privately financed project is led by Swiss engineer and businessman André Borschberg and Swiss psychiatrist and balloonist Bertrand Piccard, who co-piloted Breitling Orbiter 3, the first balloon to circle the world non-stop. The Solar Impulse project's goals were to make the first circumnavigation of the Earth by a piloted fixed-wing aircraft using only solar power and to bring attention to clean technologies.
Solar Impulse
Solar Impulse 1 – fuselage and motors
Solar Impulse 1 during its first "flea hop" test flight in Dübendorf on 3 December 2009
Solar Impulse 1 at Brussels Airport in May 2011.
Solar-powered aircraft are electric aircraft that can be an airplane, blimp, or airship and use either a battery or hydrogen to store the energy produced by the solar cells and use that energy at night when the sun isn't shining.
NASA's Pathfinder prototype
Stratobus high altitude airship