Around the World and Beyond | Bertrand Piccard

It took five minutes to work out how much energy you would need to make an airplane that could theoretically fly forever – charging batteries with solar cells during daylight to enable flying through the night. Today, with clean technologies, we can cut the energy consumption by half while being profitable. It then took seven years to make it happen. Bertrand Piccard, pilot of the first successful round-the-world solar-powered flight, explains the lessons he learned from building Solar Impulse – a venture many had thought impossible.