Since 2009, [Exxon] has endorsed a carbon tax, a position shared by many environmentalists and economists. Taxing the carbon in fossil fuels — oil, coal, natural gas — would raise their prices. That would, at least in theory, encourage energy efficiency and switching to non-fossil fuels. (Exxon Mobil prefers a carbon tax to a cap-and-trade system, which it argues is harder to administer. Many economists agree.)
Source: Washington Post
*Drudge-like creative license taken when developing that headline
