Axing coal not cutting CO2

Moving from burning coal to generating electricity from shale gas in the US is not cutting emissions as much as thought, as coal is being exported for use elsewhere, a report has warned.

Gas produces lower carbon emissions than coal, and the US is now burning less coal to generate electricity because of the development of unconventional gas reserves in shale rock.

However, millions of tonnes of unused coal are being exported to the UK, Europe, and Asia, researchers from the Tyndall Centre for Climate Change Research in Norwich said.

So while carbon emissions from the US energy sector have fallen by 8.6% since 2005, equivalent to 1.4% per year, more than half the reductions could simply have been displaced overseas as coal is exported for use in power plants abroad.

The report said a switch to shale gas would only cut emissions if the coal it displaced stayed in the ground.

The centre’s Kevin Anderson said: “Since 2008, when the shale gas supply became significant, there has been a large increase in US coal exports.

“This increases global emissions as the UK, Europe and Asia are burning the coal instead.

“Earlier Tyndall analysis suggests that the role for gas in a low carbon transition is extremely limited, with shale gas potentially diverting substantial funds away from genuinely low and zero carbon alternatives.”

John Broderick, the lead author on the report, said it was the total quantity of CO2 from the energy system that matters to the climate.

And he said: “Despite lower-carbon rhetoric, shale gas is still a carbon intensive energy source.”