Financial Times, 21 July 2015:
It may seem gratifying to learn that gas is now generating more electricity in the US than coal, particularly as this has reduced CO2 emissions by 12 per cent since 2000 (Gas overtakes coal in US electricity generation, July 13). However this may not benefit climate change because of increased methane emissions released by the fracking process. In 2011, Professor Tom Wigley demonstrated that unless fugitive methane emissions were kept below 2 percent, then shale gas was no better than coal from a climate change perspective.
Because the Bush administration granted exemptions to the fracking industry (including from the Clean Air Act) there has been no proper monitoring of methane releases in the US, but some independent studies have shown releases well above 2%. On this basis America’s new energy mix could be making climate change worse, not better.
A second problem is that US coal may simply be burnt abroad, a particular concern in Europe where dual-fired power stations are converting back from gas to coal due to cheaper imports. Finally shale gas is only acceptable if it is combined with an effective method of carbon capture. Since this is not yet available at a commercial level, it is highly misleading to present gas as any sort of solution to climate change, particularly as it is now 30 years since it was first proposed as a “bridge technology”.
Dr Robin Russell-Jones
Stoke Poges, Buckinghamshire