http://tinyurl.com/3e9awa4
* Leakage accounts for greater release of greenhouse gas
* Cornell professor comes under criticism from industry
By Daniel Trotta
NEW YORK, April 12 (Reuters) - An abundant source of U.S. natural gas widely
seen as a cleaner alternative to oil and coal is in reality the fossil fuel
that creates the most greenhouse gas emissions, a study concludes.
The paper led by Cornell University ecology professor Robert Howarth raised
howls of protest from the gas industry, which said the document was political.
The study contends that so much methane escapes from the extraction of shale
gas over the life of a well that it allows more heat-trapping greenhouse gas
into the atmosphere than coal.
The report acknowledged that natural gas is cleaner to burn than other fuels
but that greater pollution derives from leakage, whether accidental or
purposely designed to relieve well pressure.
Improved technology could solve the problem but Howarth in an interview
doubted whether that was economical considering stubbornly low natural gas
prices. A North American boom in the production of shale gas, billed as an
alternative to foreign oil, has depressed gas prices even while oil has
soared.
Industry representatives criticized the work as sloppy and incomplete
advocacy against shale gas. The shale boom previously had raised more alarm
from environmentalists because of the threat of chemicals seeping into ground
water through the drilling process known as hydraulic fracturing, or
"fracking."
For an index of shale gas companies, double-click on TRSHALEGAS.
Some 3.6 percent to 7.9 percent of the methane from shale gas production
leaks into the atmosphere, releasing a greenhouse gas that is especially
potent over the first 20 years, the study said.
"The footprint for shale gas is greater than that for conventional gas or oil
when viewed on any time horizon, but particularly so over 20 years," said the
study, which can be seen here :
http://thehill.com/images/stories/blogs/energy/howarth.pdf
"Compared to coal, the footprint of shale gas is at least 20 percent greater
and perhaps more than twice as great on the 20-year horizon and is comparable
when compared over 100 years."
Such conclusions break conventional thinking and sound outrageous to industry
representatives, who said Howarth exaggerated the amount of highly valuable
gas purportedly allowed to escape.
"The problems with the study boil down to two basic areas: the data and the
assumptions. Apart from that, Mrs. Lincoln, it's a terrific study," Chris
Tucker, spokesman for the industry group Energy In Depth, said in a statement.
"This isn't a serious academic pursuit, but rather a serious political one,"
Tucker said.
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