Methane Leak Claim More Leaky Than the Pipes

Methane Leaks - Tom Shepstone ReportsTom Shepstone
Shepstone Management Company, Inc.
   

 

Methane leaks claims in a recent study turn out to be fragile at best, dashing fractivist hopes for the illusive game-changer in war over natural gas.

When a study came out a short time ago suggesting, against all previous evidence, that methane leaks from natural gas development made a switch from diesel to natural gas less than beneficial for the climate, the fractivist contingent, including “Tony the Tiger” Ingraffea went ga-ga insisting this was a game-changer.  Like all their previous game-changers, it quickly proved to illusive as it was revealed the report was actually net-positive regarding the switch to natural gas. Now comes evidence indicating the negative conclusions seized on by fractivists are flimsy at best.

Methane - CFRThe basic flaws in the reporting on the study by the New York Times (surprise, surprise) were noted quickly by a writer at the Council on Foreign Relations (CFR) blog (see picture to right of the CFR’s headquarters in New York City). The American Natural Gas Association (ANGA) explains further in a post on its blog (emphasis added):

Over the last week, members of the energy and environment press have been aflutter about methane.  This comes in response to the release of a paper titled “Methane Leaks from North American Natural Gas Systems” in Science Magazine, whose primary claim is that there are higher-than-expected methane emissions.

It’s unfortunate that one reported finding – that there is little to no climate benefit from switching vehicles from diesel to natural gas – is not based on the paper’s data and conclusion. Brandt relies on a 2012 Proceedings of the National Academy of Sciences paper that uses an uncharacteristically low estimate of engine efficiency. The Council on Foreign Relations’ Michael Levi does a good job putting this claim into context, which you can read here.

The paper’s authors outline a number of causes for uncertainty, and so we outline them here:

  • When determining the emissions from the natural gas production process, activity data is important. Adam Brandt, the paper’s lead author, concedes this point and notes that data should improve with increased reporting requirements by the EPA.  The EPA has published data for 2011 and 2012 showing a drop in methane emissions.  While a modest drop, it occurred despite increased natural gas production.
  • Brandt also identifies clear challenges associated with estimating natural gas sector emissions by using an atmospheric approach (“top-down”).  The most significant of these being how observed concentrations of methane are attributed to potential sources.  Does the methane come from fossil sources rather than naturally occurring ones? The authors point out that studies can differentiate liquid petroleum and natural gas sources from coal, but are quick to admit that attributing methane emissions to the natural gas system is “more challenging.
  • Brandt uses EPA’s Greenhouse Gas Index as a comparative baseline to illustrate how it under-reports methane emissions compared to measurement-based studies.  Estimating methane emissions is a complex and difficult task, and it should be noted that the EPA changes its Inventory every year. The magnitude of these changes can be significant.

Some of the news coverage is perpetuating a straw-man argument by limiting the benefits of using natural gas to reduced greenhouse gas (GHG) emissions.  While lower GHG emissions are one benefit of using natural gas, it is not the only one.  Growing use of natural gas in the power and transportation sectors is helping cut hazardous emissions, increase our nation’s energy security and saving consumers money.

Despite the uncertainty surrounding the emission sources of methane, this paper makes two positive observations.  The first is that this greater-than-expected methane emissions are “unlikely to be large enough to negate climate benefits of coal-to-[natural gas] substitution.” The second is that hydraulic fracturing is unlikely to be a dominant contributor to total emissions.

There is no doubt that more information is needed to identify the sources of methane emissions, and to limit emissions during the natural gas development process.  It is encouraging that early EPA data shows progress as the industry reduces its environmental footprint.  As emissions capturing technology and so-called “green completions” are implemented across the country, we believe this downward trend will continue.

This isn’t all the CFR post uncovered either. Here’s some more from that source:

The sole sentence in the paper that addresses diesel-to-gas switching cites a two-year-old Proceedings of the National Academy of Sciences (PNAS) paper – nothing new is added. More problematic is that the 2012 paper, which is mostly excellent, stumbles when it comes to comparing diesel with natural gas.

Why? If you dig up the references that the PNAS paper uses you’ll find that it assumes CNG-fueled vehicles are 20.7 percent less efficient than diesel-fueled ones. There is a citation for this – and indeed many CNG-fueled vehicles suffer a severe efficiency penalty. But this is far from universal. Diving a couple references deep reveals that the figures are not for CNG-fueled trucks in general but for urban buses – one of the worst cases (and perhaps the worst case) for CNG. Moreover, the original reference has pretty big uncertainty bounds, though those are dropped as the paper’s contents are exploited elsewhere. A quick spin through reports unearthed by a Google search about the CNG efficiency penalty reveals a wide range of estimates – from no penalty at all to a bit north of the 20.7 percent that the PNAS authors use – depending on the engine technology chosen and how (and where) the vehicle is driven. If you adopt the more favorable estimates for the efficiency penalty – which tend to correspond to more modern engines (though not universally) and to non-urban applications – switching from diesel to CNG is indeed mildly beneficial for the climate.

So, when we get to the bottom line, the one negative from the study is nothing but a damned poor assumption.  So goes the day to day battles in the fracking war; lousy assumptions, poor data, even worse reporting and bias all the way down. Still, the truth emerges after a time, as it always does.

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4 thoughts on “Methane Leak Claim More Leaky Than the Pipes

  1. This might have little to do with this article, but it has everything to do with how it has come to this article….
    Where is the science? Old school environmentalist fought with passion to change for the better. A close friend of mine is finishing up their degree in environmental science. The university that they are attending has professors, real professors, ones that started in their field and still continue to be working and are at the top of their field still. Not resident scholars that read others work then translate. Not professors that work then were let go or sought another career as the real world work environment just didn’t “suit” them. You know the type the ones. “Those that can do, those that cant teach “. They said their professors look down on those alarmist as they have sold out the true environmentalist. The environmentalist like Patrick Moore co founder of Green Peace, Today the modern day activist alarmist works to squeeze the weak politician that thinks only of his or her power position and easy lifestyle with a forever safety net total fear of pole position and falling out of look at me syndrome. They cant think of working a real job. It frightens them to have to work with peasants and the thought of dealing with what we have to on a day to day life sends chills up their spineless backs. Here is an excellent piece that should wake the non indoctrinated to the world of Igraffea’s,Wendy Lee;s and Steingrabers. As they are the modern day bought and paid for posers that carpet bag for the elite just to stay in favor.
    http://www.foxnews.com/on-air/hannity/2014/02/28/exclusive-former-greenpeace-founders-reality-check-liberals

  2. I think a pointed question could be asked to frackivists what percentage of Gas Wells in Pennsylvania are fracked and what percentage are not ? I saw a figure that since 2006 only 7500 have been fracked out of 35000 . DO the Frackivists object to the non fracked wells that seem clearly in the majority ? I have seen the frackivists civil disobediance manual to Quebec and New Brunsiwck Canada and it seems more like they are drawing a conclusion that thumper trucks and drilling equipment means fracking automatically. Maybe these people wish for land owners to name assumptions that are wrong IE the trespassers on their land are Tree spikers , Deer jackers or common thief’s whom might be armed and dangerous ? Hey what’s good for the goose is good for the gander.

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