'Watching videos of sex and cats produces as much CO2 as half of all air transport'

Bertrand Piccard made aviation history when he became the first person to fly around the world in a plane powered only by the sun's energy. Now, he wants to use the attention generated by his journey to persuade world leaders to take radical steps to combat the environmental crisis. He spoke to Nadia Massih about whether solar planes could be used commercially, how you can be an environmental-capitalist, and his next big adventure.