American Gas - June 2013 - (Page 48)

With new data, the real impact of natural gas on greenhouse gas emissions is starting to shine through By PAmelA A. lAcey h e a dway METHANE EMISSIONS: THE REAL STORY I s natural gas good for the environment and for reducing greenhouse gas emissions in the United States? As this debate becomes more grounded in scientific fact, the answer comes back more clearly: Yes, it is. Until recently, we were not so sure this story would emerge from the jumble of hyperbole and mistaken analysis that has clogged the policy debate for the past two years. Some have even questioned the benefit of using natural gas. Poor data quality was at the root of this assertion. For many years, EPA and others have estimated the amount of methane vented or emitted from natural gas systems relying on a limited set of data collected in the early 1990s. That data served its purpose at that time, but procedures and equipment have changed significantly since then. The old study no longer provides an accurate picture of current practices and emissions. In 2011, EPA attempted to update its estimated emissions for production, relying on some information certain producers provided through EPA’s voluntary Natural Gas STAR program. Unfortunately, the agency misunderstood the submissions and— based on some incorrect assumptions about liquids unloading and well completions and workovers—EPA doubled the estimated annual methane emissions from production. As a result, EPA’s April 2011 annual Inventory of U.S. Greenhouse Gas Emissions estimated that 2.5 percent of produced natural gas was being vented or otherwise emitted from the natural gas value chain, from production well to end user—a figure that did not accurately characterize emissions. This in turn spawned a series of scientific—and not so scientific—studies asserting that methane emissions might be even higher. Better data was clearly the solution. Over the past two years, since the 2011 Inventory rocked the debate, AGA has worked with others who would like to see our nation’s energy policy decisions based on a sober, fact-based analysis. We reached out to respected environmental NGOs, such as the Environmental Defense Fund, energy think tanks, and key federal officials as well as our industry partners. And we are gaining traction. 48 AmericAn GAs june 2013 EPA recently reduced the estimated methane emissions from production by one-half, thanks to advocacy from AGA and other industry partners and new robust data collected last year. As a result, the new Inventory also cut the estimated emissions for the overall natural gas value chain by one-third. The 2013 GHG Emissions Inventory (based on 2011 data) estimates methane emissions for the natural gas value chain at 1.5 percent of produced natural gas (down from 2.5 percent in the previous Inventory). Distribution systems emit only 0.5 percent Remember that this is still an estimate, and much of it is still based on the early 1990s study. We believe the real number is even lower, and that EPA’s annual Inventories in 2014 and 2015 will get closer to this real, lower number as EPA incorporates newer data. There are two main sources of new data. First, EPA has received a wealth of emissions information on natural gas systems from reports filed in September 2012 and March 2013 under its mandatory greenhouse gas reporting program. This new data includes methane detection and measurements performed at thousands of wells, transmission compression stations, and metering and regulating stations. Second, there are several studies underway this year to obtain current data on emissions. EDF is working with industry partners and recognized academic experts to collect robust methane measurement data from natural gas production, processing, transmission and storage, distribution, and natural gas vehicle fueling and exhaust. AGA is participating in both the distribution and pump-to-wheels studies, working with our members. In addition, with support from AGA, several member companies are working with the Gas Technology Institute to measure methane emissions from low-grade leaks on cast iron, unprotected steel, and plastic distribution pipe. So we are not done yet, but we are well on our way to demonstrating the low methane emissions and huge climate benefits of using natural gas to serve this nation’s energy needs. u Pamela A. Lacey is senior managing counsel, Environment, at AGA.

Table of Contents for the Digital Edition of American Gas - June 2013

American Gas - June 2013
Contents
President’s Message
Subject Index
Safety: It Takes a Village
Digest
Issues
Update
Need to Know
Need to Know
By the Numbers
Places
On the Market
State House
Elm Street
The Calm Before the Storms
Profile 28
2013 AGA Membership Directory
Jobs
Buyer’s Guide
Marketplace
Headway

American Gas - June 2013