Charles Clover, writing in the Sunday Times (paywalled) seems to have a different understanding of the UK's shale resource to me:
Despite Tory hopes, the most optimistic estimates suggest there will be only enough shale gas — home-fracked or imported — to satisfy 15% of demand in a decade’s time, and we are likely to need that for industry and to heat our homes, not to generate electricity. The Tory frackers should reflect that it is their own rural Nimbys who are likely to ensure fracking moves more slowly on this crowded island than in the US.
This report from a year or two ago seems to suggest something very different.
He's right about the nimbies though.