What would you do if you had to power the UK? Marcus Brigstocke and Libby Purves get to grips with how to generate enough energy to keep the lights on and power their appliances. Dependency on overseas supplies, volatile fossil fuel prices and the need for a low-carbon economy makes this one of the biggest challenges facing the country. Richard Smith of National Grid and David MacKay of the DECC are our expert advisors. Chaired by Mark Lynas and using the 2050 calculator.