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.

The American Clean Energy and Security Act passed by the U.S. House of Representatives in June, aimed at reducing the pollution that contributes to global warming, would increase demand for natural gas. The bill requires power plants and other industrial facilities to reduce their emissions of carbon dioxide and similar pollutants by allotting them a diminishing number of sellable “allowances” to release these gases. This system would increase the price of electricity generated at old, inefficient power plants fired by dirty coal–making electricity from newer, cleaner, more efficient natural-­gas plants more competitive.

The House legislation would also increase investments in wind, solar, and other sources of renewable electricity. Some of these power sources are intermittent–they generate electricity only while the wind blows or the sun shines, for example. Natural gas can provide backup power when these technologies are unable to generate electricity.

Natural gas could even replace petroleum fuels for buses, heavy trucks, and fleet vehicles. Proposed legislation would require federal agencies to buy alternative-­fueled vehicles for their fleets; it would also create economic incentives for companies to purchase heavy vehicles fueled by natural gas. As a result of these policies, cleaner domestically produced natural gas would replace some of the dirtier imported petroleum we use today.

Other policies, too, could help expand demand for natural gas and decrease the pollution implicated in global warming. The starting price of pollution allowances should be raised to $14 per ton, which would come even closer to equalizing the price of electricity generated from coal and gas. We should create incentives to retire aging, inefficient, dirty coal-fired power plants and replace them with renewable and low-carbon electricity. And we need to conduct research on more efficient turbines, effective strategies for capturing and sequestering carbon emissions, and better ways to store power from renewable sources.

We must also adress the problems associated with “fracking,” a process involved in drilling for shale gas, which can pollute air and water. Any program to increase demand for natural gas must include additional environmental safeguards, such as comprehensive scientific analysis and a requirement that gas producers report their use of toxic chemicals.

Expanding the market for natural gas would increase America’s energy independence, reduce the emission of greenhouse gases, and create jobs. None of these benefits, however, will occur without comprehensive legislation.

Daniel J. Weiss is a senior fellow and director of climate strategy at the Center for American Progress.