Stephen Sackur speaks to Frances Egan, head of Cuadrilla, the company leading the charge to bring fracking to the UK. The oil price crash has put fossil fuel producers under enormous pressure. Profits are evaporating, new exploration looks like a massive gamble, and to cap it all world leaders are now committed to a radical decarbonisation of the global economy. Do the realities of economics, politics and environmental concern mean fracking has lost its appeal?