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More To Come On Methane…

Concerns around the impacts of methane emissions have reemerged in headlines, with the release of a methane leakage study about Boston. Published in the journal of Environmental Pollution a couple weeks ago, researchers from Boston University and Duke University measured atmospheric methane concentrations leaking from natural gas pipelines in Boston many of which are over a hundred years old. Another report issued last week by researchers at the Massachusetts Institute of Technology (published in Environmental Research Letters) looked at the impact of shale gas production on greenhouse gas emissions.

When talking about harmful greenhouse gases, carbon dioxide (CO2) usually gets most of the attention. Yet methane, the main ingredient in natural gas, is a short-lived greenhouse gas many times more potent than CO2 – or around 72 times more potent over a 20-year time frame. Stakes are high for the scientific community to fully understand the implications of methane leakage rates. These reports help elevate the issue that methane leakage matters to the climate and air quality, but this is only part of the story.

Methane is potentially leaking from the entire natural gas supply chain — from wells, pipelines and storage facilities — and no one knows precisely how much is leaking and where the leaks are stemming from. Some reports estimate the total methane leakage rate occurring during natural gas production, transmission and distribution to range anywhere from 1 to 7.9 percent. At the same time, the data that the Environmental Protection Agency (EPA) and everyone else rely on were collected 20 or more years ago.

A challenge for understanding the distribution of methane concentration data in Boston is that no one knows how to interpret the data yet. Maps of methane concentrations in the urban environment can be spurious. They may look scary, but are they? This and many other tough scientific questions still need to be answered, we are very early in the process of understanding how much methane is leaking and from where. The scientific community at large, including EDF and the authors of the Boston study, are committed to collecting the data necessary to addressing these concerns and to understanding the true climate impact of methane emissions.

EDF is working with leading academic researchers and industry leaders to conduct scientifically rigorous measurements of quantitative emissions across the natural gas supply chain from well to the end user. We are developing the methodologies where necessary to move past a ‘he said, she said’ conversation to one focused on data characterizing leak rates. The critical next step for us in using the increasingly robust data gathered from new innovative technologies is to precipitate a clear enough understanding of where the leaks are in the supply chain to catalyze a constructive conversation about what new policies and industry practices will be required to minimize methane leakage.

The first EDF fugitive methane report, focused on field measurements made at natural gas production sites, will be completed early next year under the leadership of the University of Texas Austin. EDF and our partners are using a diverse array of measurement techniques to characterize leak rates. We are also working to make basin-wide measurements within areas of natural gas production. Over the course of 2013 and early 2014, studies of emissions at other key components in the supply chain, including the local distribution system, will be completed and the data and conclusions released to the public.

EDF is actively campaigning to ensure that fugitive methane emissions from the natural gas industry are less than 1 percent of production in order to ensure that the climate benefits of natural gas are maximized. We see development of innovative, cost effective and accurate methane detection technologies and procedures as a necessary part of minimizing leak rates. Our view is that minimizing methane leakage is an important enough issue that we need to take the time to establish a scientific understanding of the underlying issues and by doing so defining effective well-targeted actions.

Posted in Climate, Methane, Natural Gas / Read 1 Response

New Study To Provide Important, Direct Measurement Data On Methane Emissions From Natural Gas Production

While natural gas burns cleaner than other fossil fuels when combusted, methane leakage from the production, transportation, and use of natural gas has the potential to undermine some or all of those benefits, depending on the leakage rate.  Methane is the main ingredient in natural gas and a greenhouse gas (GHG) pollutant many times more potent than carbon dioxide (CO2), the principal contributor to man-made climate change.

In other words, leaks during the production, distribution, and use of natural gas could undermine, and possibly even overwhelm, the greenhouse gas advantage combusted natural gas has over coal and spell major trouble for the climate.

Up to this point, direct measurement data on methane leakage rates has been limited and subject to wide interpretation and debate.  Some studies have estimated the leak rate to be as high as 7.9%, while others have estimated the leak rate to be as low as 1% for some aspects of the drilling process.  Methane leakage matters, and has clear implications on whether natural gas can be seen as a lower carbon energy source.  To help overcome some of the debate, EDF is working with leading academic researchers and industry leaders from across the natural gas sector to take direct measurements of leak rates to help better define the natural gas leak rate across the natural gas supply chain in the United States.

In partnership with the EDF and nine leading natural gas producers, today the University of Texas Austin (UT) announced the first part of this study, focused on emissions from natural gas production.  The study will help provide a clearer picture of methane leakage rates occurring at natural gas drilling sites around the country.  It is particularly relevant because drilling and completion processes have evolved rapidly in recent years – thanks to breakthroughs in horizontal drilling and hydraulic fracturing – and the knowledge about the methane leaked during this shift has not.

The main objective of this study on production emissions is to obtain scientifically rigorous data from multiple gas producing basins. The study will focus on quantifying emissions from well completions, gas well liquid unloading and well workovers, in addition to other more routine well-site fugitive emissions, the areas of the production process with the greatest leak rate uncertainties

The study is unique in that it brings multiple, key stakeholders to the table to make measurements of emissions at the well pad that will be shared when completed. If natural gas is to become an accepted part of an energy independence strategy, while supporting a clean energy future, it is critical to work together to quantify, and where ever possible lower, the existing methane leakage rate. Such an approach could yield enormous added environmental and health benefits from existing and future natural gas infrastructure.

A research team led by UT, including engineering and environmental testing firms URS and Aerodyne Research, is conducting the extensive field study. Project partners include EDF, Anadarko Petroleum Corporation, BG Group plc, Chevron Inc., Encana Oil & Gas (USA) Inc., Pioneer Natural Resources Company, Shell, Southwestern Energy, Talisman Energy, USA, and XTO Energy, an ExxonMobil subsidiary.

For more information on ways to get sustained benefits from natural gas, EDF published a paper earlier this year titled, “Greater focus needed on methane leakage from natural gas infrastructure.”  Find more at edf.org/methaneleakage.

Posted in Methane, Natural Gas / Read 3 Responses