Could shale gas power the world?

The amount of natural gas trapped within the shale layer under the United States is estimated at 34 times what the U.S. typically consumes in a normal year. But the methods for extracting that gas have caused controversy and debate over drilling in Pennsylvania's Marcellus Shale. Hydro-fracking, in which water and chemicals are pumped into the well at high pressure to break the shale rock and release the gas, is the common method now in use. "You bring everything the fluid encounters down there back to the surface along with the gas," said Temple environmental engineer Michel Boufadel.
March 31, 2011 | TIME