The British Geological Survey is expected to release its revised estimate of unconventional gas resources in the UK any time now. Elements of the press and some politicians continue to speculate what these figures might be, rather than wait for the figures to be published. Recent press estimates range from “Shale gas could heat all homes for 100 years” (The Telegraph 6th April, 2013 – by Louise Gray) to “Britain has shale gas for 1,500 years, but bills won’t be lower” (The Times, Feb 9th, 2013 – by Dominic Lawson).
The BGS figures should provide us with a better estimate than previously available. However, it is worth noting that:
- Only a portion of the gas in the ground is technically recoverable, perhaps between 10% and 20%.
- Only a portion of what is technically recoverable will be economically recoverable – no one currently knows how much.
- In the South West 26% of households are not on the mains gas network, including entire villages in the Chew Valley. These households use other energy sources including bio-fuels such as wood, and fossil fuels such as oil, propane and liquid natural gas (methane). Some households use no fossil fuels for either heating or electricity.
Based on the existing British Geological Survey Estimate Professor David MacKay of Cambridge University, who is also the Chief Scientific Adviser to the Department of Energy and Climate Change, has said:
“It is conceivable that the technical potential of shale gas in the UK could be very large: shale gas tends to be found wherever there is coal, and the British Isles were blessed with a very large endowment of coal – a Saudi Arabia’s worth, roughly – so it is credible that the quantity of shale gas “in place” is comparably large. However, the quantity “in place” is not the same as the technically recoverable resource, which may be much smaller, since fracking typically releases only a minority of the gas that is in place. Indeed it still remains perfectly possible that the technically recoverable resource (at an economic price) could be zero, because the yield from shale deposits varies by more than a factor of ten, depending on the precise chemical and mechanical properties of the host rock. Those who say that the recoverable resource is enormous are cherry-picking the most optimistic projections of yield, based on the most productive shales in the USA. But there is no reason to believe that the UK’s shales will have a productivity that is at the high end of the range. The truth is that we don’t yet know. This large uncertainty about the resource will be reduced if and when exploration and extraction take place in the UK; meanwhile, one central estimate of the UK’s technically recoverable shale gas resource is the British Geological Survey’s estimate of 5.3 trillion cubic feet (150 bn cubic metres). To put this quantity in context, UK natural gas consumption is roughly 100 bn cubic metres per year, so the BGS estimate corresponds to 1.5 years’ consumption. When DECC receives any updated advice from the BGS, we will put this information on the DECC website.”
Commenting on another article by Dominic Lawson on climate change in the Independent newspaper, Professor MacKay has noted that “irresponsible journalism like Dominic Lawson’s deserves a good flushing”.