Reuters: A climate change deal is needed not just to ward off global warming, but to ensure a shift from increasingly costly fossil fuels that could lead to a doubling of energy bills, the IEA’s chief economist said on Tuesday. In the absence of an agreement, the ratio of energy spending to Gross Domestic Product for the largest consumer countries would double by 2030, Fatih Birol, author of the International Energy Agency’s World Energy Outlook (WEO) told Reuters in an interview. "The …