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15 April 2011

Cornell Study Shows Shale Gas Has Much Larger Greenhouse Gas Emissions Than Coal and Oil

By Nathanael Baker on April 12, 2011

A forthcoming study [pdf] from Cornell University may dash the growing reputation natural gas has acquired as the "clean" burning fossil fuel.

According to research conducted by Robert Howarth, Renee Santoro, and Anthony Ingraffea, greenhouse gas emissions produced by natural gas derived from unconventional sources, primarily hydraulic fracturing, are significantly higher than that of conventional gas, coal, and oil.

Methane, a powerful greenhouse gas, is a significant component of natural gas. The authors estimate that between 30% and 200% more methane is emitted from shale gas produced from hydraulic fracturing, or fracking, wells. Hydraulic fracturing requires injecting pressurized water into rock formations to crack them open and harvest the gas encased within them. The majority of the methane escapes in the water as it flows back out, and then later, when the rock is further drilled open to extract the gas reserves.

Howarth and his team state the greenhouse gas footprint of shale gas is substantially greater than conventional gas and oil, and coal, especially when viewed over a 20-year time period. "Compared to coal, the footprint of shale gas is at least 20% greater and perhaps more than twice as great on the 20-year horizon and is comparable when compared over 100 years."

With the United States sitting on the largest known reserve of shale gas, the energy source has quickly won a host of powerful supporters. Oil tycoon T. Boone Pickens has called natural gas the only energy source which can reduce emissions while supplying an answer to the country's quest for energy independence.

Pickens has revamped his Pickens' Plan -- a blueprint to transition America from foreign fossil fuels to clean energy sources -- so that it almost exclusively focuses on natural gas development. Currently he is pressing American lawmakers to pass the NAT GAS Act which would provide federal incentives for natural gas, while failing to fund other alternative fuels. Last week the NAT GAS Act was introduced in Congress.

Pickens states the President is supportive of this bill, and he may very well be right. President Obama has insisted it is time for America to eliminate its dependence on foreign oil. Although the President concedes it will take a myriad of energy sources to provide the nation with energy independence, natural gas appears to be the most tantalizing at the moment.

When he recently unveiled his own blueprint for energy independence the President placed particular emphasis on natural gas: "Recent innovations have given us the opportunity to tap large reserves -- perhaps a century's worth -- in the shale under our feet. The potential here is enormous."

The energy potential may be enormous, but likewise so are the environmental liabilities. The Cornell study, which will be published this month in the peer-reviewed journal Climatic Change, asserts that life-cycle emissions produced by hydraulic fracturing have not thoroughly been examined. Even more, Congressmen as well as the Environmental Protection Agency (EPA) assert other environmental hazards such as dealing with the toxic flow-back water still need to be addressed. Multiple communities have reported drinking water contamination as a result of the toxic waste being injected into nearby water streams.

A recent New York Times investigative report show the politics around regulating hydraulic fracturing have existed since the Reagan administration. The EPA is currently conducting a study of the environmental impacts posed by fracking, but nevertheless, this latest study will likely add more fuel to the controversy surrounding one of the most popular new energy sources in the world.

Image credit: COTO Report

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