September 21, 2011
The following is an excerpt from a point/counterpoint article by Prof. Robert Howarth (EEB) and Prof. Tony Ingraffea (CEE) in Nature (the international weekly journal of science):
“Natural gas from shale is widely promoted as clean compared with oil and coal, a ‘win–win’ fuel that can lessen emissions while still supplying abundant fossil energy over coming decades until a switch to renewable energy sources is made. But shale gas isn’t clean, and shouldn’t be used as a bridge fuel.
Shale rock formations can contain vast amounts of natural gas (which is mostly methane). Until quite recently, most of this gas was not economically obtainable, because shale is far less permeable than the rock formations exploited for conventional gas. Over the past decade or so, two new technologies have combined to allow extraction of shale gas: ‘high-volume, slick-water hydraulic fracturing’ (also known as ‘fracking’), in which high-pressure water with additives is used to increase fissures in the rock; and precision drilling of wells that can follow the contour of a shale layer closely for 3 kilometres or more at depths of more than 2 kilometres (see ‘Fracking for fuel’). Industry first experimented with these two technologies in Texas about 15 years ago. Significant shale-gas production in other states, including Arkansas, Pennsylvania and Louisiana, began only in 2007–09. Outside North America, only a handful of shale-gas wells have been drilled.
Counterpoint: No, it’s too valuable
by Terry Engelder (Pennsylvania State University – Department of Geosciences)
“Fracking is crucial to global economic stability; the economic benefits outweigh the environmental risks…”