Reducing oil and gas operations’ methane emissions is an essential, but far from the only, part of a comprehensive climate strategy, speakers at a Center for Strategic and International Studies event agreed. Efforts should be combined with an aggressive program to curb excessive carbon dioxide releases, they said.
Controlling both would address methane’s more immediate and powerful damages and broader problems caused by growing CO2 levels, the speakers said. It also would preserve prospects that abundant domestic natural gas resources will be more fully developed, they added.
“Basically, a third of climate change comes from short-lived pollutants,” said Steven Hamburg, chief scientist at the Environmental Defense Fund. “Methane is about half of that. It’s not a 100-year problem, but one that goes over 20 years. Methane emissions can be captured mainly in their first 20-40 years. After that point, it becomes CO2.”
David Allen, who directs the University of Texas at Austin’s Energy and Environmental Resources Center, said that methane emissions information has grown dramatically the past several years from a combination of aerial and ground-level monitoring. The latter already has shown that locks, unloadings, and pneumatic controllers are dominant wellhead emissions sources, he said.
Regional differences can be wide for several reasons, according to the two speakers who worked on a new methane emissions report UT-Austin and EDF plan to release jointly on Dec. 9. “Different places have different levels so national levels aren’t useful,” Hamburg said on Dec. 8. “Having the most comprehensive range possible would be.
“There are regional differences from regulation as well as geology,” said Allen. “I think we’re approaching a point where we can deploy monitoring networks to help us identify wells that are turning into problems and correct problems before they happen.”
Identified problems
Even areas that already have been identified as having many problems would not necessarily benefit from national regulations in all cases, Hamburg said. “We have to determine which are performing badly, but we also have to accept that in the case of pneumatic controllers, a third of the devices perform well with no emissions,” he explained. “We have better information now. There are different flavors of pneumatics, for example.”
Hamburg said there doesn’t appear to be a fundamental problem with methodologies, but added: “We have to be careful how we collect data. When we do, we find that numbers start to come together. But we need to do this across the energy chain. Right now, we have almost no information on end-users.”
Tackling methane emissions provides the federal and many state governments an easier way than usual to reduce global climate change, noted two regulators who were part of a second panel that also included three oil and gas industry representatives.
“It’s an opportunity we don’t normally have,” said Janet McCabe, the US Environmental Protection Agency’s acting assistant administrator in the air and radiation Office. “Companies want to tackle this because the gas that doesn’t escape is gas they can sell. It’s very encouraging that a methane emissions data system is up and running at so many wellheads. We have a proposal to extend reporting obligations to other parts of the value chain.”
The Obama administration committed to get more specific proposals from a variety of other federal agencies this fall, she continued. “At EPA, this involves achieving more reductions while communicating with other federal agencies and continuing to work closely with the states,” McCabe said. The federal agency provides technical assistances to states and tries to make certain regulations it contemplates don’t undermine state rules that go further, she said.
Colorado went first
Colorado became the first US state in February to adopt regulations aimed at controlling upstream oil and gas operations’ methane emissions, noted Martha Rudolph, who directs environmental programs in the state’s Public Health and Environment Department.
“Up to 98% control of hydrocarbon emissions from underground tanks is required now, which us down closer to the levels we want,” she said. “This regulation created a pretty robust initial monitoring system that can be extended into other areas.”
When Gov. John W. Hickenlooper (D) proposed at a 2012 Colorado Oil and Gas Association event that the state adopt regulations to control methane emissions, the PH&E Department found itself working with about 100 stakeholders, Rudolph said. The state encouraged them to form smaller groups to develop proposals; three oil and gas producers and EDF did, which provided the basis for the rules that were adopted ultimately.
Once the rules became final, COGA and the Colorado Petroleum Association announced they would help their members begin training exercises to comply, she indicated. “Relations between communities, industry and other stakeholders already existed, which helped us develop the requirements,” Rudolph said.
Royal Dutch Shell PLC believes controlling methane emissions is important, and is working to reduce them voluntarily, reported Greg Guidry, executive vice-president for unconventional resources in the Americas. “We also recognize that voluntary efforts by a handful of companies aren’t going to be enough,” he said.
Backs targeted approach
Shell would like to see EPA and other federal agencies take a targeted, thoughtful approach to curb methane emissions from identified upstream sources, he said. “If EPA is committed to a regulatory approach, we believe it should avoid a broad regulation which would impose unnecessary costs,” Guidry said.
Engagement with communities near potential E&P sites begins very early worldwide, he continued. “If we don’t feel as good about what I call our social seismic before we began working in the subsurface, I’m not comfortable,” he said.
Pioneer Natural Resources Co. is focusing on environmental stewardship, adjusting operations to comply with new air regulations, striving for operations excellence, and participating in industry emissions studies, according to Carrie Reese, the Dallas independent producer’s environmental compliance manager.
“Our goal is to reduce emissions beyond what regulations propose,” she told the CSIS audience. “We implemented green completions well in advance of regulations. Our new wells are typically connected to pipelines before completion. We also extended leak detection to pipelines, batteries, wells, and compressor stations. We have thermographers on-staff who are able to detect and repair leaks.”
For pneumatic controllers, which studies have identified as a trouble spot, Pioneer is examining alternatives to running them with natural gas, Reese said. It already uses compressed air instead where it has a large number of pneumatic controllers, she said.
Pioneer also tries to generate new data to improve national estimates because it recognizes this helps the company, Reese said. “We realize that with additional production comes a potential for more emissions,” she said. “We want to strike a balance between regulation and production.”
What LDCs are doing
American Gas Association Pres. David K. McCurdy said the nation’s more than 200 investor-owned local distribution companies are reducing methane and other emissions as they upgrade pipelines to make them safer. “Since 1990, emissions have fallen 22% as our members added more than 600,000 miles of distribution pipelines,” he said.
State public utility commissioners will need to strike a regulatory balance as gas prices remain low, McCurdy said. “Unlike producers, our members are the public face of gas. They interface with the consumer,” he said.
He said 38 states have programs to facilitate replacing and modernizing distribution systems. Accurate emissions data will help build an understanding of where future improvement is needed, and Washington State University is working on a study to quantify emissions through local gas systems, McCurdy said.
In response to a question about Hamburg’s earlier observation that emissions information is thinnest at the local level, AGA’s president said state public utility commissions approach leaks from a safety standpoint. LDCs’ systems also are primarily in urban areas, he added.
“Our members have to coordinate with water systems and other utilities, which drives costs up,” McCurdy said. “These are not taxpayer dollars, but investments. Our members want to move ahead on getting more emissions information.”
“I think the context is an increasing awareness of methane’s role in global emissions,” said EPA’s McCabe. “There also are significant, more traditional air pollution benefits proceeding with these programs. We also are working closely with our partners at [the US Department of the Interior and Bureau of Land Management] so we don’t duplicate or overlap.”
Fonte: http://www.ogj.com
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