From Green Right Now Reports
A Cornell review of natural gas extraction methods reveals that ‘fracking’ gas from the Marcellus Shale region of New York and Pennsylvania could release dangerous amounts of methane gas, causing more damage to the atmosphere per pound than even carbon dioxide.
Natural gas, which burns cleaner (producing less carbon dioxide) than gasoline, diesel fuel and coal has been touted as a greener “bridge fuel” that could power cars and replace coal in power plants. Tailpipe emissions from natural gas-powered vehicles emit few greenhouse gases.
But Cornell ecologist Robert Howarth warns that the natural gas extraction or drilling process releases dangerous amounts of methane, a greenhouse gas far more potent than carbon dioxide. The methane leakage is the worse when the gas is accessed by the hydraulic fracturing or ‘fracking’ methods that have become popular with the industry. Fracking is a way of teasing out deeply embedded gas deposits using high pressure water injections in wells that run both vertically and horizontally through shale deposits.
Natural gas, in fact, is mostly methane, and pound for pound has 105 times more warming impact than carbon dioxide, says Howarth, in a statement on the Cornell study, which is being published in the May issue of the peer-reviewed journal Climatic Change Letters.
Even small leaks from gas wells can be damaging, Howarth says, because as much as 8 percent of the methane in shale gas leaks into the air during the lifetime of a hydraulic shale gas well. The leakage can be double that of a conventional gas well.
“The take-home message of our study is that … shale gas is worse than conventional gas and is, in fact, worse than coal and worse than oil,” Howarth said. “We are not advocating for more coal or oil, but rather to move to a truly green, renewable future as quickly as possible. We need to look at the true environmental consequences of shale gas.”
Howarth, a professor of ecology and environmental biology, Tony Ingraffea, professor of engineering, and Renee Santoro, a research technician in ecology and evolutionary biology, analyzed data from published sources, industry reports and the Environmental Protection Agency to compile their study.
They compared estimated emissions for shale gas, conventional gas, coal (surface-mined and deep-mined) and diesel oil, taking into account direct emissions of CO2 during combustion, indirect emissions of CO2 necessary to develop and use the energy source and methane emissions, which were converted to equivalent value of CO2 for global warming potential, according to a Cornell University statement on the study.