IEA: Global Gas Reserve Estimates Doubled

The world may have twice as much natural gas than previously thought, according to the International Energy Agency (IEA).

In a report this week, Anne-Sophie Corbeau, a gas analyst at the IEA, said global gas reserves could have a lifespan of more than 250 years through unconventional gas reserves, including shale,  roughly doubling previous estimates.

"The gas story is huge," she said.

She said there was "probably" more than "300 times" more unconventional gas on hand than the current annual demand for gas. Not all of the gas locked in hard-to-reach formations is exploitable, however.

Advocates point to the clean-energy gains from natural gas. Fatih Birol, the chief economist at the IEA, told the BBC that burning natural gas produces half of the emissions of coal.