We just added a brief on natural gas  to its Climate TechBook  that helps to explain why natural gas is unique among fossil fuels. Natural gas is both a contributor to climate change (natural gas combustion accounts for about 16 percent  of total U.S. greenhouse gas emissions) and an option for reducing emissions since natural gas is less carbon-intensive  than coal and petroleum. The United States could actually reduce total greenhouse gas emissions by burning more natural gas if it’s displacing other fossil fuel use (this is particularly the case for fuel switching from coal to gas in power generation).
Like coal, but unlike petroleum, natural gas is primarily a domestic energy resource, with net imports of natural gas constituting only about 13 percent  of U.S. consumption and about 90 percent of imports coming from North America. Unlike coal (93 percent  consumed for electricity generation) and petroleum (more than two thirds  used for transportation), natural gas consumption is more evenly split  across the electric power, industrial, residential, and commercial sectors.
The past few years have seen a “revolution ” in the outlook for natural gas supply. Until recently, experts thought that the United States would become increasingly dependent on expensive imports of liquefied natural gas (LNG) from overseas, but the recent boom  in domestic “unconventional” gas production (driven by shale gas ) and the dramatically increased estimate of U.S. gas reserves  have led to projections  of increasing domestic natural gas production and declining imports.
Natural gas is receiving a lot of attention in the discussion about U.S. climate and energy policy. The gas industry is pressing  for favorable treatment in possible climate and energy legislation, with a specific set of policy priorities  recently put forth by a major industry lobby group.
While some tout natural gas as a “bridge fuel” to a low-carbon future others fear that a “dash for gas ” (i.e., fuel switching by electric power generators) could increase demand for and the price of natural gas, thus negatively impacting manufacturers that rely on natural gas for energy and as a feedstock.
Recent analysis  by the U.S. Energy Information Administration (EIA ) of the climate and energy bill passed by the House in June 2009, illustrates how the projected role of natural gas in reducing U.S. greenhouse gas emissions depends in large part on the use of offsets under cap and trade and the relative cost and commercial availability of low-carbon technologies (e.g., wind , solar , carbon capture and storage , and nuclear power ). When low-carbon technology deployment and offsets are constrained, EIA finds a much heavier reliance on natural gas for electricity generation under cap and trade, but the new outlook on U.S. natural gas supply means that even this pessimistic scenario  does not lead to major increases in projected natural gas prices.
A new modeling analysis  from Resources for the Future (RFF ) sought to quantify the implications of the dramatically expanded U.S. natural gas supply. RFF researchers found that without new energy and climate policy, more abundant and less expensive natural gas could actually mean slightly higher  U.S. greenhouse gas emissions in 2030 than would otherwise be the case (as cheaper natural gas competes with non-emitting energy sources and increases total energy consumption).
This last point brings us back to the overarching importance of implementing a policy that puts a price on carbon, as a greenhouse gas cap-and-trade program would do. Putting a price on carbon would harness market forces to drive the deployment of a portfolio of low- and lower-carbon technologies and fuels, including increased natural gas use to the extent it can cost-effectively reduce emissions.
Steve Caldwell is a Technology and Policy Fellow