Credit: Nick Reddyhoff

Natural gas is the cleanest fossil fuel--it produces half as much carbon pollution as coal, and one-third less than oil per unit burned. Recent advances make it affordable to develop the natural gas found in shale deposits, so we have more of this resource than was previously thought: at current production rates, there could be enough recoverable fuel to supply the United States for the next 90 years (see "Natural Gas Changes the Energy Map"). This offers an opportunity to use natural gas as a bridge to a clean-energy economy that relies on efficiency, renewable power sources, and low-carbon fossil fuels.

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