3D graphic of shale deposit
Media playback is unsupported on your device

Energy alternative: Shale gas extraction in the US

21 December 2010 Last updated at 23:09 GMT

As this winter's freezing weather puts great pressure on gas supplies, countries are using new technology to exploit existing energy reserves.

The US is extracting gas from shale rock, cutting bills for consumers, and reducing the country's reliance on foreign suppliers.

Roger Harrabin reports from Shreveport in Louisiana.