© Solar Impulse

Will future flights go solar? Airlines may be experimenting with biofuels on today’s airplanes, but the aircraft of tomorrow may run on solar power. In 2010, the Swiss-engineered Solar Impulse, a long-range glider equipped with 12,000 solar cells, made a 26-hour solar-powered flight within Switzerland. In 2011, Solar Impulse flew from western Switzerland to Brussels in 13 hours. A larger prototype is scheduled to fly around the world in 2013.

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