Energy company Cuadrilla said Friday it has extracted shale gas in Britain for the first time since resuming fracking operations it halted in 2011 over environmental concerns.
The 11-year-old British private firm has borne the brunt of protests for trying to test whether fracking __ a process in which water and chemicals are used to blast apart rock formations __ can unlock natural gas deposits in Britain.
The method has transformed the global energy market but is developing slowly in Europe.
"The volumes of gas returning to surface at this stage are small," Cuadrilla chief executive Francis Egan said of the fracking site in northwestern England.
"However it provides early encouragement that the Bowland Shale can provide a significant source of natural gas to heat Lancashire and UK homes and offices and reduce our ever growing reliance on expensive foreign imports," he said in a statement.
The British Geological Survey estimates that the site Cuadrilla is exploring holds up to 2,300 trillion cubic feet (90 trillion cubic metres) of shale gas.
The amount could theoretically fill Britain"s natural gas needs for more than a thousand years.
Cuadrilla is trying to find out how much of that potential reserve can be reached and produced at commercially viable levels.
- Energy security -
Government data show natural gas being used to meet about 40 percent of Britain"s power and nearly 90 percent of its heating needs.
But UK gas production rates have been falling and it became a net importer of the fuel in 2004.
Firms such as Cuadrilla hope to step in and begin meeting some of the demand now primarily supplied by energy-rich Norway.
Cuadrilla produced small amounts of shale gas at the same site seven years ago.
It was forced to halt operations because two small earthquakes were soon registered nearby.
Cuadrilla resumed work on October 15 after adopting more stringent safety and regulatory measures that environmentalists said were still insufficient.
The company has since been forced to briefly halt drilling on three occasions because minor tremors began being detected deep underground.
Cuadrilla stressed at the time that none could be felt or cause physical damage on the surface.
"This Preston New Road site is being monitored to an unprecedented level," Egan said in Friday"s statement.
Greenpeace UK chief John Sauven called the fracking announcement a blow to campaigners" efforts to win government backing for alternative fuels such as wind power.
"It is truly bewildering how little fossil fuel companies need to offer in order to get whole-hearted, full-throated government support, and how much clean technologies can offer and still be blocked," Sauven said.
Cuadrilla said on its website that tests from 2011 suggest it can produce 6.5 billion cubic feet of shale gas over 30 years at the site.
By Dmitry ZAKS