4th March 2014
Shale UK conference report 1
To recover 15 per cent of shale gas from the Upper Bowland Basin in Lancashire would need 33,000 wells on 5,500 pads, an industry conference heard today.
The estimate by Andy Aplin, Professor of Unconventional Petroleum Development at Durham University, is based on research published last year into production levels from 8,000 wells in the Barnett shale gas field in the United States.
Professor Aplin, a former adviser to BP, told the Shale UK conference in London the density of production in the Upper Bowland Basin would need to be one pad of six wells per 2km square. 15 per cent of recovery, he said, was 40 trillion cubic feet or 13 years’ of UK gas use.
To be independent of gas imports, Professor Aplin said, Britain would need to drill 1,000 wells a year nationwide from 150 pads. He contrasted this with the average of 19 onshore wells drilled in the UK each year between 1902 and 2013 and the 50-150 UK wells drilled annually offshore.
Another speaker, Lord Oxburgh, former chairman of Shell, explained why the drilling density would need to be so high. He said US experience showed that production from shale gas wells declined very rapidly. The flow rates of the majority of American shale wells halved in the first 12 months. 84% of wells became uneconomic within three years. “You need more drilling [for shale] than you need for a conventional operation”, he said. “We should think of this as natural gas mining”. Lord Oxburgh said Britain would also need many exploration wells because so little was known about the UK’s recoverable shale gas.
Huw Clarke, senior geoscientist with Cuadrilla Resources, which holds a production and exploration licence in the Bowland Basin, challenged whether current American production experience was relevant to the UK. He said all the wells he visited recently were operating only to hold on to the lease until the US gas prices rose, when the operators would increase production.