Guardian: Richard Branson has failed to deliver on his much-vaunted pledge to spend $3bn (1.8bn) over a decade to develop a low carbon fuel. Seven years into the pledge, Branson has paid out only a small fraction of the promised money well under $300m according to a new book by the writer and activist, Naomi Klein. The British entrepreneur famously promised to divert a share of the profits from his Virgin airlines empire to find a cleaner fuel, after a 2006 private meeting with Al Gore. Branson went...