Reuters: A reduction of ten percent in oil demand could knock about $20 off the price of a barrel of crude by 2035 if nations meet their climate change pledges and cut fossil fuel subsidies, the International Energy Agency says. “The weaker and slower the response to the climate challenge, the greater the risk of oil scarcity and the economic cost for consuming countries,” the Financial Times on Thursday quoted a draft of the 2010 World Energy Outlook (WEO) as saying. The report by the IEA, which advises…