Shale gas has been called a ‘glint of hope’ for climate change; a ‘global phenomenon’ for domestic energy security around the globe; and is a centre piece of the IEA ‘golden age of gas’ that could potentially supply the world’s energy requirements for 250 years.

But several important studies, including one released this week for the European Parliament [PDF], have argued that the conventional resource potential of shale gas might be significantly overstated and importantly, that the risks to human health and the environment may outweigh the benefits.

On the surface, the switch to gas can bring some immediate advantages over other options for nations aiming to decarbonise their energy spectrum: gas generates around half the carbon when burned for power generation; it is a more efficient fuel for transport and, it is cheaper than oil. In addition, shale gas could effectively eradicate the dependency of many countries to importing energy: a particularly poignant point when European gas production has been in steep decline for many years (is expected to drop some 30% by 2035) when European demand for gas has been increasing substantially.

Dig a little deeper, however, and it may begin to sound too good to be true. The extraction process, known as hydraulic fracking (or fracking), uses heavily pressurised liquids to break geological hydrocarbon formations which in turn make previously unconventional sources of gas (and in some circumstances oil as well), conventional. The overall production of shale gas is widely believed to contribute to uncontrolled releases in methane (a greenhouse gas 21 times the global-warming potential of carbon dioxide); it can contaminate ground and surface fresh-water sources with harmful chemicals, and worryingly, can even cause localised earthquakes.  A study by Cornell University estimates that when compared with coal, the emissions footprint from shale gas may be some 20% worse in the short-term, and potentially double the GHG impact on the 20-year horizon.

The EU report goes on to explain that while European developments have been relatively small in comparison to other countries (US and China for instance), major regulatory gaps concerning shale gas extraction and production mean shale gas is currently provided ‘privileges’, and thus could expose Europe to unreasonable environmental and human health risks if these gaps are exploited.

With uncertainty surrounding nuclear energy, prolonged future oil price rises and the wonder of potential energy independence, many governments are already looking for alternatives to fill the energy gap for the next decade. It may yet come with a slightly gaseous flavour but, for the moment, the jury is still out. In any case let’s hope that decisions are based on balanced facts and not merely on potentials, which clearly are as staggering in scale as the potential risks.

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