Prediction, as Mervyn King once observed, is ‘a stab in the dark’. Who can say with confidence where the wholesale price of electricity will be in ten years’ time, let alone 45 years hence at the end of the contract struck by Energy Secretary Ed Davey with EDF of France for the building of the £16 billion Hinkley Point nuclear station? We can be pretty sure the price will be a lot higher than today’s and it’s not mad to think it might have doubled by 2023, which is the starting assumption of the EDF deal.