We underestimate the power of the world that surrounds us and ignore the potential of its energy at our cost. Richard Hamblyn blends history and science to highlight the power of the earth and our vulnerability, and asks why we don't learn from the lessons of the past. Leading solar expert Jeremy Leggett presents a groundbreaking vision of a sun-powered world, debunking the myths to reveal a future re-energised by the light in the sky.