The British Geological Survey (BGS) says the UK has large amounts of shale hydrocarbons below its surface. However, the precise distribution is not yet well known and there remains significant uncertainty over how much is extractable.
The BGS has examined how much shale resources there are in several areas of the UK. Its central estimates for these are:
- Over 1,300 trillion cubic feet (tcf) of shale gas in the Bowland-Hodder shale in Lancashire;
- Around 4.4 billion barrels (bbl) of shale oil in the Weald basin in Sussex, but no significant gas resource;
- A further 1.1bbl of shale oil in part of the Wessex basin, near the Weald basin and;
- And around 80tcf of shale gas and 6bbl of shale oil in the Midland Valley of Scotland.
Two things are worth emphasising here. First, these are central, fairly rough estimates. The BGS’s range for the Bowland-Hodder shale, for example, is a lower limit of 822tcf and upper limit of 2281tcf.
Most importantly, though, these are calculations of the total resources of shale. Only a fraction of this will be commercially extractable reserves, depending on the cost of UK operations and the international market price of gas.
The BGS says it is too early to know what proportion of UK shale resources are recoverable, although it says US recovery factors are typically around 10%. Note that shale firms often argue they need to begin drilling before they can understand how much of the UK’s shale gas is extractable.
The UK uses around 3tcf of gas each year. Assuming a 10% recovery rate and the BGS’s central estimates, the UK has 138tcf, or around 46 years worth of technically extractable shale gas.
It’s worth noting a 2013 assessment by the US Energy Information Administration (EIA) estimated a far lower technically recoverable resource in the UK of 26tcf, equivalent to nine years of current UK gas use
A 2010 BGS estimate for the Department of Energy and Climate Change (DECC) put the “total recoverable reserve potential” in the UK even lower, at just 5.3tcf. This is less than two years of use.
Research by UK-based commercial oil and gas consultancy the Energy Contract Company (ECC), published in 2012, put technically recoverable shale gas far higher than this, at 40tcf, around 13 years worth.
Meanwhile, in 2013 the Parliamentary Office of Science and Technology (POST) estimated a potentially recoverable resource of 64-459tcf in the Bowland shale formation alone. This figure is based on a range of recovery rates of 8-20%.
There are currently no official reserve estimates. As POST observes, UK reserves could be anywhere from “zero” to “substantial”. It says: “To determine reliable estimates of shale gas reserves, flow rates must be analysed for a number of shale gas wells over a couple of years.”
Ken Cronin, Chief Executive of UK Onshore Oil and Gas, said: “The option of producing onshore gas here with high environmental standards, compared to transporting gas halfway around the world from countries with lower environmental standards, has obvious environmental and economic benefits.
“When considering environmental aspects alone, shale gas is more sustainable than solar and published Environment Agency statistics show that onshore oil and gas is one of the best performing sectors in the UK when it comes to environmental performance.”
15 Jan 2018