21 January 2014
Fracking: this is how this controversial technique works
Fracking is a technique used to extract gas that is trapped deep below the Earth's surface. Rock is fractured by injecting high-pressure water and chemicals to release the gas. The larger availabity of gas through this technique has substantially lowered energy prices in the US. However, the technique is controversial because of pollution and the large number of boreholes needed to extract gas on a commecial scale