May 30, 2012. The U.K.'s energy policies may fail to deliver nuclear power and renewables needed for the nation to meet its goals for reducing greenhouse gases, the International Energy Agency said. Britain's new electricity generation capacity is coming mainly from natural gas fired plants, the Paris-based agency, which advises 28 nations, said in a report. The report underscores pressure on Prime Minister David Cameron's government to overhaul the power market in a way that both stimulates investment in new generation capacity and keeps power prices from rising too quickly. The IEA said Britain needs 110 billion pounds ($173 billion) invested in in the industry by 2020 to meet electricity demand. U.K. utilities must replace 12 gigawatts of aging coal and oil- fired plants and 7 gigawatts of atomic reactors by 2020, the IEA estimated. Parliament is considering a draft energy bill that would guarantee returns for nuclear and renewable power.