Solar power is a growing global phenomenon but in Arizona, one of the sunniest US states, solar power hasn't taken off. The BBC's economics correspondent Andrew Walker explains why from the state capital Phoenix. Also, our regular US commentator James Srodes reports on the biggest-ever US oil find and how it might help the presidency of Donald Trump. And we speak to Ole Harms, chief executive of Moia, Volkswagen's new digital business division, about a future of driverless cars.
(Photo: Solar panels being installed in Arizona, Credit: Getty Images)