Methane emissions from gas production lower than EPA estimates, study says

Researchers from the University of Texas at Austin said their direct measurements at 190 natural gas drilling sites found lower methane emissions than the US Environment Protection Agency has suggested in earlier estimates.

The UT measurements summary found wells generally emitted about 20% less greenhouse gases than EPA had estimated. Proceedings of the National Academy of Sciences published the study, “Measurements of methane emissions at natural gas production sites in the United States” on Sept. 16.

UT chemical engineering professor David Allen and other researchers measured methane emissions from shale gas wells completed with hydraulic fracturing. The study results released so far involved only the gas extraction phase.

Allen said the information will help policymakers make informed decisions. Meanwhile, more work is pending on other possible industry sources of methane emissions, such as pipelines.

Sponsored by the Environmental Defense Fund and natural gas producers, the study concluded that methane emissions from the development of gas and associated liquids represent 0.42% of total production.

Large oil companies contributed financing to the study. They include Anadarko Petroleum Corp., ExxonMobil Corp., Pioneer Natural Resources Co., and Royal Dutch Shell PLC.

Meanwhile, Physicians, Scientists & Engineers for Healthy Energy called the study “fatally flawed” because of the sample size and industry influence. But UT researchers said their methodology was sound and the research was done independently.

Trade associations last year reported in a joint study of their own that EPA estimates on methane emissions from unconventional gas production were too high (OGJ, July 2, 2012).

Industry reacts

The American Petroleum Institute said the UT study’s findings demonstrate industry’s successful efforts to reduce GHG emissions.

Howard Feldman, API director of regulatory and scientific affairs, said industry will continue making progress to reduce emissions voluntarily and in compliance with EPA’s recent emissions standards. “Capturing methane is helping operators deliver more natural gas to consumers, creating a built-in incentive to continue reducing these emissions,” Feldman said.

He emphasized the study results help show that additional regulation on top of existing federal, state, and local regulations are not necessary.

“In fact, safe and responsible development of energy from shale has helped the US cut carbon dioxide emission to near 20-year lows.” Feldman said.

Erica Bowman, vice-president of research and policy analysis for America’s Natural Gas Alliance, also welcomed the study results.

“We are continually putting into operation equipment and practices that demonstrate our commitment to lower emissions in the production process,” Bowman said. “We look forward to working with stakeholders to ensure the best science is applied in future study of this issue.”

EDF said the report marked the first of 16 methane emissions studies in a comprehensive initiative. The study marks what EDF calls “the opening chapter in this broader scientific effort designed to advance the current understanding of the climate implications of methane emissions resulting from the US natural gas boom.”

Fred Krupp, EDF president, acknowledged that “immediate methane reductions are critical to slow climate change,” adding, “But we don’t yet have a handle on how much is being emitted. We need better data, and that’s what this series of studies will deliver.”

He said new EPA wellhead emission regulations are effective. The overall research effort started last year to measure methane emissions associated with  gas production, gathering lines and processing facilities, long-distance pipelines and storage, local distribution, and commercial trucks and refueling stations.

Various scientific methods are being used across the various studies, including approaches that measure emissions directly at the source and those that use airplanes or towers equipped with sensors to measure total emissions in a given area.

EDF anticipates all will be submitted for publication in peer-reviewed journals. The overall effort is scheduled to be completed in late 2014.

Study findings

The initial study report noted that findings showed higher emissions from pneumatic controllers and equipment leaks than EPA emission estimates. There was significant geographic variability in emissions from pneumatic pumps and controllers, researchers said.

The 190 onshore gas sites used for measurements involved the Gulf of Mexico coast, Rocky Mountains, and Appalachian regions.

Emission measurements were performed for 27 well completion flowbacks, 9 liquids unloadings, 4 well workovers, and 150 production sites of which 489 wells involved hydraulic fracturing.

“One important result from the measurements…is that current EPA estimation methods overpredict measured emissions,” the study said in its findings on unloadings. “There are multiple methods of unloading a gas well, some of which do not result in emissions.”

The UT-led study involved sampling performed for unloadings in which an operator manually bypassed the well’s separator.

Researchers said the overall implication is “a large uncertainty” in the national emissions from gas well unloadings. “It is also clear from the data that properly accounting for unloading emissions will be important in reconciling emission inventories with regional ambient measurements.”

Contact Paula Dittrick at paulad@ogjonline.com.

Related Articles

EPA approves Magellan’s Corpus Christi splitter project

12/12/2014 The US Environmental Protection Agency has issued a final greenhouse gas prevention of significant deterioration construction permit to Magellan Pr...

Keyera to take majority interest in Alberta gas plant

12/12/2014 Keyera Corp., Calgary, will pay $65 million (Can.) to buy a 70.79% ownership interest in the Ricinus deep-cut gas plant in west-central Alberta.

PBF Energy, PBF Logistics make management changes

12/12/2014 Matthew Lucey, currently executive vice-president of PBF Energy Inc., will succeed Michael Gayda as the company’s president. Todd O’Malley, current...

TAEP: TPI still peaking, but ‘contraction unavoidable’ as oil prices fall

12/12/2014 The Texas Petro Index (TPI), a composite index based on a comprehensive group of upstream economic indicators released by the Texas Alliance of Ene...

MARKET WATCH: NYMEX crude oil price extends slump

12/12/2014 Crude oil prices extended their slump on the New York market with a Dec. 11 settlement of less than $60/bbl for January, and prices continued downw...

US needs more data before ending crude export ban, House panel told

12/11/2014 Much more environmental impact information is needed before the US can reasonably remove crude oil export limits, a witness told a House Energy and...

BOEM raises offshore oil spill liability limit to $134 million

12/11/2014 The US Bureau of Ocean Energy Management increased the liability limit for oil-spill related damages from offshore operations to $134 million from ...

Rosneft, Essar sign terms of oil supply agreement

12/11/2014 OAO Rosneft and Essar Energy PLC have signed key terms of an oil supply agreement in New Delhi. Rosneft said shipments to India may begin in 2015.

Barton introduces bill to remove US crude export limits

12/11/2014

US Rep. Joe Barton (R-Tex.) introduced legislation that would remove US crude oil export limits that have been in place for nearly 40 years.

White Papers

AVEVA NET Accesses and Manages the Digital Asset

Global demand for new process plants, power plants and infrastructure is increasing steadily with the ...
Sponsored by

AVEVA’s Approach for the Digital Asset

To meet the requirements for leaner project execution and more efficient operations while transferring...
Sponsored by

Diversification - the technology aspects

In tough times, businesses seek to diversify into adjacent markets or to apply their skills and resour...
Sponsored by

Engineering & Design for Lean Construction

Modern marketing rhetoric claims that, in order to cut out expensive costs and reduce risks during the...
Sponsored by

Object Lessons - Why control of engineering design at the object level is essential for efficient project execution

Whatever the task, there is usually only one way to do it right and many more to do it wrong. In the c...
Sponsored by

Plant Design for Lean Construction - at your fingertips

One area which can provide improvements to the adoption of Lean principles is the application of mobil...
Sponsored by

How to Keep Your Mud System Vibrator Hose from Getting Hammered to Death

To prevent the vibrating hoses on your oilfield mud circulation systems from failing, you must examine...
Sponsored by

Duty of Care

Good corporate social responsibility means implementing effective workplace health and safety measures...
Sponsored by

Available Webcasts


On Demand

Optimizing your asset management practices to mitigate the effects of a down market

Thu, Dec 11, 2014

The oil and gas market is in constant flux, and as the price of BOE (Barrel of Oil Equivalent) goes down it is increasingly important to optimize your asset management strategy to stay afloat.  Attend this webinar to learn how developing a solid asset management plan can help your company mitigate costs in any market.

register:WEBCAST


Parylene Conformal Coatings for the Oil & Gas Industry

Thu, Nov 20, 2014

In this concise 30-minute webinar, participants have an opportunity to learn more about how Parylene coatings are applied, their features, and the value they add to devices and components.

register:WEBCAST


Utilizing Predictive Analytics to Optimize Productivity in Oil & Gas Operations

Tue, Nov 18, 2014

Join IBM on Tuesday, November 18 @ 1pm CST to explore how Predictive Analytics can help your organization maximize productivity, operational performance & associated processes to drive enterprise wide productivity and profitability.

register:WEBCAST


US HYDROCARBON EXPORTS Part 3 — LNG

Fri, Nov 14, 2014

US LNG Exports, the third in a trilogy of webcasts focusing on the broad topic of US Hydrocarbon Exports.

A discussion of the problems and potential for the export of US-produced liquefied natural gas.

These and other topics will be discussed, with the latest thoughts on U.S. LNG export policy.

register:WEBCAST


Careers at TOTAL

Careers at TOTAL - Videos

More than 600 job openings are now online, watch videos and learn more!

 

Click Here to Watch

Other Oil & Gas Industry Jobs

Search More Job Listings >>
Stay Connected