In western Pennsylvania, in eastern Ohio, in Texas and Oklahoma, from Colorado to Arkansas to New York, there’s an energy boom in progress. It’s big enough to make the United States energy-independent by 2030, according to some experts, and it may account for 50% of US natural gas production by then.
It’s hydraulic fracturing, and the technology’s potential to unlock enormous and previously inaccessible reserves of domestic natural gas, coupled with its possible environmental risks, made it the focus of a National Academy of Engineering topical meeting held June 18-19 at Case Western Reserve University in Cleveland.
How big is the current push to increase US shale gas production? In 2000, shale gas accounted for only one percent of domestic production, according to one industry analyst. In 2011, that figure was 25 percent, and in 20 years shale gas may account for 50 percent of domestic production. According to a forward-looking report (pdf) recently released by energy company BP, “From 2011 to 2030 shale gas more than trebles and tight oil grows more than six-fold. Together they will account for almost a fifth of the increase in global energy supply to 2030.” Development of shale gas could also eliminate the need for US natural gas imports in the same time frame, the report adds.
Speakers at the well-attended meeting pointed out that fracking is not new—it has been used to increase production in conventional oil and gas wells since the 1940s. What is new is the combination of hydraulic fracturing and horizontal drilling, which allows creation of multiple horizontal wells radiating like spokes from a wheel for a mile or more from a single surface wellhead drilled vertically to the required depth. Now these technologies are being used to release natural gas locked up in shale deposits across the US—no mean feat, considering shale has about the same permeability as steel, according to one presenter at the meeting.
Just as the combination of fracking and horizontal drilling can exponentially increase production, the process also results in added potential environmental hazards. For one thing, it requires large volumes of water, which is pumped into the wells to fracture the gas-bearing rock. The water is treated with a variety of chemicals, and about 25 percent of it eventually returns to the surface where it requires treatment for reuse and eventual disposal. Other possible environmental issues associated with fracking include surface and groundwater contamination, air pollution, and even the possibility of induced earthquakes if shale formations are fractured too near an existing natural fault.
Despite these potential risks, one expert who has studied the process extensively said at the meeting that fracking to release the US’s shale gas deposits not only can be done safely, but it must be done safely. He called shale gas “a blue bridge to a green future,” saying increased domestic natural gas production can meet US energy needs through 2050, when other, renewable technologies presumably will be available to pick up the slack.
Ceramic materials have a role to play in the fracking process, from the clays and cements used to ensure well integrity to the proppants—hard particles 0.5 to 2 mm in diameter—used to hold open the microfissures created by fracking that allow the gas to flow. ACerS will be covering use of ceramic technology to improve fracking productivity and safety in the coming months.