Scientists have discovered huge coal deposits under the North Sea that could power Britain for centuries.
Data from North Sea oil and gas exploration has been used to build a picture of the large coal deposits.
"We think there are between three trillion and 23 trillion tonnes of coal buried under the North Sea," Dermot Roddy, former professor of energy at Newcastle University, told the Sunday Times.
"This is thousands of times greater than all the oil and gas we have taken out so far, which totals around 6bn tonnes. If we could extract just a few per cent of that coal it would be enough to power the UK for decades or centuries," he continued.
Geologists are yet to discover the scale of the coal deposits, despite already knowing that Britain's coal resources stretched out into the North Sea.
Roddy is to reveal plans to sink the first boreholes by the end of 2014 at a Royal Academy of Engineering conference.
Professor of petroleum exploration at Imperial College London Richard Selley said that such discoveries of unconvential energy stores were "gamechangers".
"A decade ago the talk was all about peak oil and gas but that has gone out of the window," he said.
"The big game-changer is seismic imaging, which has become so sensitive that we can now pinpoint the 'sweet spots' where shale gas, oil and coal are to be found.
"There have also been huge improvements in horizontal drilling . . . and in hydraulic fracturing [fracking], which lets us get the gas and oil out of rock. If we put aside the green issues, then in perhaps 10 years we could be self-sufficient in gas and possibly oil too."
Energy companies previously deemed such stores inaccessible but technological advances such as gasification have allowed underground pumps to turn the coal into gas useful for power-generation.