Telegraph: The Renewable Energy Strategy will state that more than £100 billion needs to be invested in infrastructure, including 7,000 wind turbines, by 2020. It is estimated in the strategy that energy bills will have to rise by about 20 per cent to cover the cost. The average household pays about £1,150 a year for electricity and gas, so the cost of converting to renewable energy and modernising the power supply could add about £230 to bills. The Government is legally tied to …