There have been a number of independent estimates of the amount of natural gas that will actually be extractable from the Marcellus Shale via fracking that revise downward industry estimates. And last week TreeHugger had a fact-check on President Obama's exaggerated statement on the longevity of the US natural gas supply more broadly (100 years, as the President claimed? Not so much. Not by a long shot.)
Well, the Energy Information Agency has just weighed in on how much natural gas both the US has as a whole and the Marcellus Shale specifically contains, confirming that it's far less than the industry or politicians routinely claim.
No need to belabor the point, as the New York Times does an excellent job of it, but as the result of better data becoming available, as fracking has rapidly expanded in the past year,
[The EIA] estimated that there are 482 trillion cubic feet of shale gas in the United States, down from the 2011 estimate of 827 trillion cubic feet — a drop of more than 40 percent. The report also said the Marcellus region, a rock formation under parts of New York, Ohio, Pennsylvania and West Virginia, contained 141 trillion cubic feet of gas. That represents a 66 percent drop from the 410 trillion cubic feet estimate offered in the agency’s last report.
So how long would the gas in the Marcellus Shale last? Based on current natural gas consumption levels, six years.