Tuesday, June 14, 2011

Frack it!

A genuine revolution is underway in the energy sector, now that new methods are being used to extract ever larger amounts of natural gas. The gas, known as ‘coal seam gas’ or ‘shale gas’, is extracted from underground rocks by injecting them with large quantities of water and sand under high pressure. This causes the rocks to fracture, releasing the gas contained inside them. The process is called ‘fracking’. After it has been extracted, the gas can be used just like conventional natural gas. Large reserves of gas are available for extraction in this way, especially in Australia, Canada and the US, where more shale gas is now being extracted than conventional gas. There is probably a large amount of this type of gas in the Slochteren gas field in the Netherlands, too. The energy sector is embracing these new methods of production enthusiastically because gas is a much cleaner source of energy than coal, and it could therefore be used as a temporary replacement for coal until more sustainable forms of energy become available on a large scale. Burning natural gas produces much fewer pollutants than burning coal.

However, there is also growing criticism of this use of ‘clean’ fossil fuels. Natural gas is methane, a greenhouse gas that remains a hundred times more powerful than CO2 for twenty years after it is extracted. The problem is that a small percentage of this hyperactive greenhouse gas will always escape into the atmosphere during extraction, processing and transportation. In fact, American researchers have recently discovered that the negative effect of shale gas on the climate could be up to 20% greater than the effect of burning coal. And other environmental drawbacks are also being encountered. At the end of May, residents living near a shale gas extraction site in Arkansas in the USA made a damages claim for 4.75 billion US dollars against the Australian company BHP Billiton, which is responsible for the production of shale gas there. They claim that the extraction process has led to the pollution of ground and surface water, and even to an earthquake with a magnitude of 4.7 on the Richter scale. Shell, which extracts coal seam gas in Queensland in Australia, recently had to deal with a gas and water explosion. Various governments are now being persuaded to tighten up the environmental regulations on extracting shale gas. Although the first results of this seem to indicate that the emission of methane into the atmosphere can be reduced, it is still unclear whether this can prevent all the damaging effects. So it remains to be seen whether the initial euphoria over these new, clean forms of fossil energy will prove justified.

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