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CORRECTION: This story was updated on May 10, 2012, to correct the following statement: “CH4 is far less abundant in the atmosphere than CO2—about 9% versus 82%, according to the Energy Information Administration (EIA).” The passage now reads: “CH4 is far less abundant in the atmosphere than CO2. According to the Energy Information Administration (EIA), CO2 makes up 82% of annual U.S. anthropogenic greenhouse gas emissions, and CH4 makes up 9%.”
The U.S. is on a natural gas binge. In a mere half-dozen years, natural gas production and prices have been transformed. Thanks to a new unconventional natural gas technology—hydraulic fracturing—the nation has seen natural gas production go from a trickle to a flood.
So-called fracking is based on improvements to a technology developed decades ago by the Department of Energy. By forcing millions of gallons of water under high pressure into shale and tightly bound sand structures, natural gas and oil drillers fracture rock and nearly impenetrable sand, freeing previously untapped fossil fuels and driving them to the surface.
It’s a messy business. People living in communities where fracking is taking place, sometimes right on their doorsteps, say their drinking water has been contaminated and their homes, property values, and quality of life have been ruined. Now, a growing number of scientists, health professionals, and residents worry about air pollution from the chemical compounds—which include methane, a potent greenhouse gas and the primary component of natural gas—that come up with the oil and gas.
On the other hand, the new natural gas finds have U.S. industry abuzz with hopes of an economic bonanza, particularly the chemical and electricity sectors, which use natural gas as a feedstock and fuel. U.S. chemical companies are watching profits soar with cheap natural gas and ethane, a key liquid feedstock that accompanies the gas, and they have announced plans to construct new chemical plants using ethane as raw material (see page 29). Also, new gas-fired electricity power plants are in the works and coal-fired power plants are shifting from coal to natural gas. Gas imports to the U.S. are at the lowest level since 1992, and prices are less than half of those only a few years ago (C&EN, March 5, page 10).
Environmental groups and others concerned about air pollution and climate change have also embraced the change from coal to gas, because natural-gas-fired power plants emit at least 40% less carbon dioxide and none of the mercury that comes with coal combustion. They are particularly pleased to see the shutdown of some of the dirtiest U.S. coal-fired plants, which have provided most of the nation’s electricity for decades.
However, natural gas and oil drilling and production also releases a host of air pollutants as well as methane. During its first 12 years in the atmosphere, methane is 72 times more potent a greenhouse gas than CO2, says the Intergovernmental Panel on Climate Change. Oil and gas production is the largest source of man-made methane emissions.
The increased use of fracking is likely to magnify this trend. The Environmental Protection Agency, which has not regulated air pollution or greenhouse gas emissions from oil and gas drilling and production, estimates that some 25,000 new oil and gas wells will be fractured or refractured annually. Overall, the agency says, about 1.1 million wells are producing oil and gas in the U.S.
Most of the new air emissions, however, will come through the fracking process, a significantly larger generator of air emissions than conventional drilling. With fracking, most of the emissions come during the “flowback” and production process in the oil and gas fields. Some 2 million to 4 million gal of water, along with fracking fluids and sand or other material, is forced under high pressure more than a mile under the Earth’s surface to open fissures and release the oil or gas. The injection of this material and its return to the surface may take three to 10 days before actual production begins, according to industry and EPA material. Along with oil and natural gas come methane, volatile organic compounds (VOCs), sulfur dioxide, toxic air pollutants, and sand, as well as a mix of other waste material.
Since the mid-1990s, EPA has run a voluntary program to encourage industry to reduce these emissions. But the air emissions from fracking and the lack of a formal rule to reduce emissions prompted concerned groups to sue the agency.
As a result, a court order handed down more than a year ago required EPA to issue final air regulations for oil and gas drilling under the Clean Air Act. EPA proposed air regulations last July after litigation from two local groups in the Southwest, where large-scale fracking has led to a demand for regulation.
The final air regulation has been delayed by EPA four times—the original deadline set by the court was November 2011. The agency is now expected to issue the final rule this week. EPA blames the delay on time needed to address concerns raised in more than 156,000 public comments.
As proposed, EPA’s regulation does not address methane. Instead it focuses on VOCs, sulfur dioxide, and toxic air pollutants, such a benzene, ethylbenzene, and n-hexane, according to EPA.
Leaked methane is to be recovered by better practices and new equipment used to collect other pollutants, particularly VOCs. The captured methane can then be sold to pay for the cost of implementing the regulation. EPA pegs the lost methane during gas drilling and processing to be 2 to 3% of production.
“This is a unique regulation, as the control technology generates value and pays for itself,” says Ramón Alvarez, a senior scientist and chemist with the Environmental Defense Fund (EDF).
The most attention has been on a system of what EPA calls green or reduced emissions completions (REC). The system includes movable equipment that separates gas and liquid hydrocarbons from other flowback materials and allows methane to be captured as a cobenefit. EPA’s proposed regulation would apply only to new drilling operations.
The agency estimates that the new equipment would cost some $754 million but would capture over $783 million worth of natural gas, ethane, and other condensates that would have been lost to the atmosphere each year. The regulation, EPA says, would net the industry $29 million in annual savings.
Others peg the possible income from lost methane much higher. The Natural Resources Defense Council, an environmental group that has done its own studies, says the captured methane could bring more than $2 billion in annual revenues.
For its part, the oil and gas industry says that it may be as long as seven years before sufficient REC equipment is available. The industry also says that it’s already taking steps to capture methane.
A voluntary survey of member companies of America’s Natural Gas Alliance (ANGA), an oil and gas trade association, found that 93% of some 1,500 wells had installed equipment to reduce methane releases. Survey participants, however, were self-selected. EPA puts the number at 15% of wells.
A more important part of the debate, however, is just how much methane is lost during fracking. Methane is key because EPA estimates that about half of total global methane emissions are from human activities and nearly 40% of anthropogenic CH4 emissions are from natural-gas-related systems. Of these, the lion’s share—or 64% of emissions—is from natural gas and oil production, 18% from natural gas transmission lines and storage, 11% from distribution, and the rest from downstream activities.
While CH4 is 21 times more potent in warming the atmosphere than CO2 over a 100-year timescale, it is a much more potent greenhouse gas over shorter periods before it breaks down to CO2 and water. During its initial 12-year chemical lifetime in the atmosphere, methane’s global warming potential is 72 times more potent than CO2’s. Overall, however, CH4 is far less abundant in the atmosphere than CO2. According to the Energy Information Administration (EIA), CO2 makes up 82% of annual U.S. anthropogenic greenhouse gas emissions, and CH4 makes up 9%.
The large initial climate-change impact of methane over a short time worries Robert W. Howarth, a professor of ecology and environmental biology at Cornell University. He and several other Cornell professors are mostly concerned about the high methane losses from fracking during the next 10 to 35 years, when methane’s ability to influence the climate is greatest. Howarth says climate-change gains from switching power plants from coal to gas may be offset by the amount of methane lost from fracking.
In a recent study (Clim. Change Lett., DOI: 10.1007/s10584-011-0061-5), Howarth has estimated that methane leakage from the well sites makes up 2.2 to 4.3% of production, higher than EPA’s estimate of 2 to 3%.
Howarth’s findings are similar to a recent study by the National Oceanic & Atmospheric Administration. NOAA scientists find leak levels nearly twice EPA’s estimate. In the study (J. Geophys. Res., DOI: 10.1029/2011jd016360), NOAA team members were surprised to discover unusually high levels of air pollutants, particularly benzene and methane, at an air-monitoring tower in Colorado, north of Denver.
The researchers determined the emissions to be coming from a northern Colorado oil field with some 14,000 operating oil and gas wells. Methane leakages were about 4% of production, says Gabrielle Petron, the lead researcher and a NOAA atmospheric scientist.
“We may have been significantly underestimating methane emission by this industry in this region,” she adds. The researchers also suspect VOC emissions from oil and gas processing may be underestimated.
Both the American Petroleum Institute (API), another oil and gas trade association, and ANGA say the estimates are far too high. Spokesmen for the two associations acknowledged, however, that they did not know how much methane is lost during drilling. Both also said industry studies are under way. Their studies will join several other ones, including a joint examination by industry and EDF.
But Howarth says the exact level is not his primary concern—time is. Weighing CH4 releases over a 100-year period, as is done for more long-lived CO2 emissions, weakens the climate-change impact from methane.
Howarth’s view is supported by recent studies by Drew T. Shindell, a climatologist at the National Aeronautics & Space Administration’s Goddard Institute for Space Studies, who has stressed the importance of slowing climate-change impact in the short term by reducing shorter-duration but higher-potential greenhouse gases, such as methane, rather than focusing on CO2 (C&EN, Jan. 16, page 30).
Citing Shindell, Howarth says the next 35 years are critical to avoid reaching a “tipping point” when temperature increases of 1.5 to 2 °C could occur because of methane.
Several scientists and energy policy analysts are uncomfortable with Howarth’s leakage assumptions as well as his use of a shorter period to project methane’s global- warming impact. They also take issue with his allegations that fracking emissions of methane will make natural-gas-fueled power plants lose their greenhouse gas advantage over coal-fired power plants. They say Howarth has failed to consider the efficiency advantages of natural gas power plants. They also believe industry will be driven to reduce methane leaks simply to save money.
However, other climate scientists and policy analysts say the 100-year time frame in the case of methane is inaccurate and greatly weakens the role the gas plays. Additionally, these scientists note that while gas producers may want to save product and limit leaks, drilling contractors are often hired to set the well and are less concerned about leaks than completing the well. And they also worry that if Howarth and Shindell are correct, humans may find it very difficult to bring climate change under control.
For the chemical industry it is essential to keep the gas flowing, says the American Chemistry Council, a chemical industry trade association. Natural gas and ethane are “like flour for a baker,” Calvin M. Dooley, president and chief executive officer of ACC, said at a natural gas seminar last month.
“There has never been a better time to be part of the U.S. chemical industry,” Dooley told the audience. When he took over ACC three years ago, Dooley noted, U.S. chemical companies had just lost 140,000 jobs and faced a bleak future where plants were shutting down and jobs and production facilities were heading to parts of the world where production and feedstock costs were less.
Fracking and the abundance of natural gas and ethane changed all that.
“Since 2005, the U.S. chemical industry has moved from a high-cost chemical producer to one of the lowest-cost producers in the world,” Dooley said. The advantage is due to the cost of gas compared with oil. European and many other chemical makers rely on oil-based feedstocks, such as naphtha. In international competition, ACC figures show a favorable product advantage for U.S. chemical companies when the price ratio of oil to gas is 7 to 1. Currently, it is 55 to 1, ACC says.
Dooley sees a “renaissance” in chemical production on the horizon that will be so great that it will transform all U.S. manufacturing. Ninety-six percent of all manufactured products—from tires and auto parts to solar panels and insulation—are made in part from chemical-industry-supplied raw materials, he said. Hence, he sees a heyday in U.S. overall production.
The importance of the jobs that come with this transformation is not lost on Congress in this election year.
Last month, members of the Senate and House of Representatives both weighed in on fracking. Sen. James M. Inhofe (R-Okla.) and several other top Senate Republicans introduced legislation that would block EPA from regulating fracking and leave such regulation to the states. Pointing to EPA’s proposal, Inhofe accused the Obama Administration of seeking to “eliminate hydraulic fracturing.”
In the House, Republican leaders of the Energy & Commerce Committee wrote EPA Administrator Lisa P. Jackson and challenged parts of the proposed regulation, saying it would cut unconventional sources of natural gas 37% by 2015, citing figures developed by API.
In late March, Jack N. Gerard, API president and former head of ACC, took his objection directly to President Barack Obama in the form of a letter to the President’s senior adviser, Valerie Jarrett. Urging that the regulation be softened and the time to implementation be delayed, Gerard wrote that the regulation will “result in a substantial slowdown in drilling operations.”
On the other hand, pressure on the oil and gas industry to clean up its operations is coming from many quarters.
For instance, a March 27 letter—released by Ceres, a nonprofit organization that supports sustainable investing—urged 21 oil and gas CEOs to clean up their fracking emissions. The letter was signed by 37 institutional investors with $500 billion in assets and warned that without action methane loss is “ultimately threatening the industry’s license to operate.”
Similarly, a report late last year by a DOE oil and gas expert panel, the Secretary of Energy Advisory Board Shale Gas Production Subcommittee, warned that with some 100,000 new natural gas fracturing wells planned for the next few decades, there is “a real risk of serious environmental consequences causing a loss of public confidence that could delay or stop this activity.”
The advisory board urged EPA to include methane explicitly in its air regulations and to have the regulations cover existing and new wells. Also the board urged the oil and gas industry to unilaterally lead in reporting and reducing its air emissions.
In today’s intense political climate and in an election year in which the economy and jobs have been thrust to the fore, many eyes will be watching EPA’s new Clean Air Act regulation. ◾
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