Holding out the prospect of vast new domestic reserves, the natural gas industry is promising to make the United States an energy-rich nation once again. But we should be careful what we wish for. Spending those riches could endanger water supplies for millions of Americans while still failing to solve the climate crisis.
Electric utilities have expanded their use of gas because gas-fired plants can be "turned up" to meet high peak power demand more quickly than can coal-fired plants. Natural gas is also more climate-friendly than coal and less menacing than nuclear energy.
With the discovery of drilling techniques that can extract natural gas from deep shale formations, the authoritative Potential Gas Committee estimates that the total of confirmed and potentially accessible reserves has grown 35% in just three years.
Climate bills in the House and Senate contain strong incentives to increase drilling and burning of natural gas (1). Seized by anti-coal fervor, most major environmental groups have gone along with the gas rush.
But natural gas is "clean" only in contrast to coal--just as a bacon cheeseburger can be regarded as healthful compared with a double bacon cheeseburger. Per kilowatt of electricity generated, gas releases 55% as much carbon as coal, based on total 2008 energy output and emissions for the two fuels. And gas drilling poses a growing threat to our water supplies.
The investigative news organization ProPublica has documented thousands of cases of surface and groundwater contamination caused by drilling in conventional and shale deposits in six states.
Concern is now growing over hydraulic fracturing, in which water laced with sand, clay and "fracturing fluids" is pumped deep underground to create fissures and free gas trapped in rock formations. Most of the polluted water returns to the surface and must be handled as waste.
Drilling in shale, which depends heavily on fracturing, can consume hundreds of times more water per well than does drilling in traditional gas fields.
In Pennsylvania, which shares the vast, gas-laden Marcellus shale formation with four other states, drilling is expected to generate 19 million gallons of waste water daily by 2011, according to the state's Department of Environmental Protection. The water, which carries both natural and human-made toxins and is up to five times as salty as sea water, puts a heavy burden on water treatment plants. New York residents are working to prevent drilling in...