This group brings together the best thinkers on energy and climate. Join us for smart, insightful posts and conversations about where the energy industry is and where it is going.


Gas: the bridge to nowhere?

David Lewis's picture
  • Member since 2018
  • 353 items added with 39,387 views
  • Nov 30, 2010

I corresponded with Dr. Robert Howarth since I posted an article about his research into the climate impact of gas here last week.  Howarth is the scientist who is saying gas has a greater climate impact than coal. 

 Howarth emailed to say his opinion is based on several points.  One, the latest research indicates methane has about 30% greater climate impact than the IPCC AR4 stated, and two:  “I believe they are severely underestimating the methane leakage”.    

GWP charts


Howarth drew my attention to  the work of Dr. Drew Shindell, a senior climate scientist at NASA G.I.S.S. who published new data on methane in October 2009.  Shindell was the lead author of a paper published in Science.  Here is the press release

The work of Dr. Shindell’s group is solid.  They were able to quantify and add in the effects of methane/aerosol interactions which the IPCC’s AR4 couldn’t include because the discovery was made after its cutoff date of May 2006 . 

 “What happens is that as you put more methane into the atmosphere, it competes for oxidants such as hydroxyl with sulphur dioxide…   More methane means less sulphate, which is reflective and thus has a cooling effect. Calculations of GWP [a way to calculate climate impact] including these gas-aerosol linkages thus substantially increase the value for methane.”    (this Shindell quote is from this article)

Shindell says “although our calculations are more complete than previous studies”, he knows he hasn’t accounted for everything.  But he said the nature of what is not certain enough to include in calculations now “would simply increase” his calculated value for methane as opposed to other gases he studies.  I.e., the GWP numbers for methane “may still be too low”.

 Howarth believes Shindell’s data is good.  He wrote in his email: “several of the IPCC authors responsible for the AR4 figures agree with me that it is appropriate to use the most recent estimates”

 Keith Shine, of the University of Reading, one of the originators of the GWP concept, said that Dr Shindell’s work would help to refine this. “It does change the picture quite significantly,” he said.  – (this quote is from this article)

 On Howarth’s second point, that most analysts “severely” underestimated leakage:  he mentioned several papers.  I haven’t had time to assess these.  I put them up here because The Energy Collective had a Webinar discussing natural gas Nov 30. 

Howarth:  “We believe leakage is at least 1.9% and perhaps 5.6% or greater”.  Howarth’s high end figure of 5.6% makes gas worse than coal even if viewed over 100 years.

We’ll discuss why Howarth believes leakage could be this high in a moment, but first let’s have a word from an industry determined to keep on ignoring the problem that environmentalists still support because they bring us all this ‘green’ gas.  Here is a Youtube video showing methane leaking from industrial sources.


This photo of an oil storage tank at the left looks ‘normal’ but the same tank photographed on the right with an infrared camera shows the methane pouring out.


Methane shows up clearly on infrared precisely because it presents such a strong barrier to infrared radiation, i.e. it is a potent greenhouse gas. This is how hard a gas leak is to find.  You get an IR camera, point it at your equipment, and you get a picture like this.  This picture was also published in an article in the NYTimes. A large section of US industry can’t be bothered to do it. 

(An aside:  Revkin at Dot Earth, in Keeping Natural Gas in Pipelines, Not Air notes that a lot of gas companies continue to ignore leaks, even though companies such as BP have shown for the last decade that stopping leaks saves three times as much money as it costs.  This is one result of BP “accepting the message from the rocks”, i.e. taking global warming as serious, compared to the typical US company attitude.  And here’s another post of Revkin’s, i.e.  “A Greenhouse Gas that is already a Commodity”  The point Revkin makes in this is that unlike the proposed carbon price on CO2, there is already a price on natural gas.  Gas is what the industry sells.  Even that price doesn’t make them control their emissions, unless intangibles are mixed in, like our CEO says we have to do it because he’s brought in a new company slogan (“Beyond Petroleum”) and he’s out there making speeches to the G8 admitting that he believes that climate change is serious.)

Back to Howarth.  According to him, “the DOE ignores a lot of information” on leaks. 

He cites as one example the paper “Estimate of methane emissions from the US natural gas industry” which he says shows the DOE ignores accidents, and that the DOE only studied plants the industry wanted them to study.  Chemosphere 35:  1365-1390  (Sorry about no live links to some of these papers:  I got them from behind paywalls from a computer at the university)

 To illustrate that the DOE approach was verified to be too low at processing plants and refineries Howarth cites, as an example: “Direct Measurement of fugitive emissions of hydrocarbons from a refinery” Journal of the Air and Waste Management Association 58:  1047-1056 

Howarth also said for “well-head” emissions, “which the DOE seems to ignore”, “we rely heavily on industry” sources, i.e. for example, Shires, (2009) Compendium of Greenhouse Gas Emissions Methodologies for the Oil and Natural Gas Industry.  August 2009.  Prepared by the URS Corp. for the American Petroleum Institute (API).  API, Washington D.C. 

 And he states “for our low end estimate of leakage from pipes we used the latest direct measurements from… Europe (there are no data in the US)”.  He noted that: “these are low, since they do not include accidents, etc.  Note that these pipelines are newer than the average for the US”.  And for the high end estimate, he says:  “we used accounting data for lost and unaccounted for gas in Texas”.  He says “this gives us a range that is within that reported by one of the only other peer reviewed papers out there, with a similar mean”.  The paper he refers to here is Hayhoe  “Substitution of natural gas for coal:  Climatic effects of utility sector emissions.”  Climatic Change 54:  107-139

(Note:  one panel member on The Energy Collective Webinar “Natural Gas: Friend or Foe to Energy Sustainability”, after deflecting a question about Howarth’s research by referring to a summary of his preliminary work done months ago which he described as not “impressive”, claimed European natural gas use results in essentially “zero” emissions of methane.  We’d like to see some “impressive” research backing this statement up sometime.)

Howarth says that Hayhoe et. al. found that “coal is better than gas for many scenarios going out for several decades”, but “if you use the latest GWP from the 2009 Science paper it makes the gas far worse“  And he pointed out that the assumptions Hayhoe made about methane leaking from coal processing are not supported by IPCC data, in other words coal is better than the Hayhoe paper assumed. 

 A last point Howarth made is that studies of radiocarbon in methane that is currently in the atmosphere mean that “the amount of methane coming from fossil sources is much greater than has been estimated in the past”.  He cites Lassey et. al. “The atmospheric cycling of radiomethane and the ‘fossil fraction’ of the methane source”  Atmospheric Chem. & Physics 7: 2141-2149 (2007)   

Many people would like to ignore this research.  There is a lot of momentum behind using natural gas as a “bridge” fuel.   As Michael Brune, director of the largest environmental group in the world, the Sierra Club, tells us:  “we need to use natural gas as our country makes the transition from the dirtiest energy sources (coal and oil) to clean and renewable sources like wind and solar.”  (the quote is from his blog)

 One reason methane gets little attention was described on NPR:

 “Mohamed El-Ashry at the United Nations Foundation says part of the reason has been a fear by governments and advocates that attacking methane would be a dangerous distraction.  “People are worried about diverting attention away from carbon dioxide,” he says.”

 But this is getting preposterous.  Shindell published another chart in his paper in Science I referred to above.  He calculated the total effect methane has had compared to CO2 from 1750 to 2000, to warm the planet, taking his new research into account:

 chart from shindell


Methane has been about 60% as large as the CO2 part of the driving force for climate change all this time. 


Dr. Shindell has been studying methane for a long time.  E.g.:  see this paper published in 2005. 









When Shindell writes about what needs to be done about climate, as he did in his “Climate Change is All About Energy” he says “fossil fuels” are the problem.  He doesn’t separate gas from coal.  He writes “improvement in renewable energy from wind, solar, and nuclear power should be at or near the top of national priorities”.  He calls for more “efficiency”. 

 But Shindell laments:  “Continued use of fossil fuels is inevitable for the immediate future, and potential solutions such as carbon sequestration and nuclear power require further study or remain controversial” 

Perhaps its time to make the use of natural gas controversial.    


David Lewis's picture
Thank David for the Post!
Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.
More posts from this member
Spell checking: Press the CTRL or COMMAND key then click on the underlined misspelled word.
David Lewis's picture
David Lewis on Nov 30, 2010

Oil that comes out of the ground isn’t like the oil that people buy to put in their cars.  It happens that oil, before it is refined, can contain methane.  My understanding is that if you put the unrefined oil into a storage tank above ground, as its temperature increases, the methane bubbles out, something like when you open a can of a soft drink. You have to invest a bit more in building the tank to fit it with a methane recovery system.  They couldn’t even be bothered to gather this stuff up and flare it somewhere.  Its too much trouble. 

Environmentalists who believe gas is “green” have given them a free pass on this kind of thing – they are too focussed on making sure picocuries of radiation scare everyone into believing nuclear power shouldn’t be employed to put these fossil fuel companies out of business. 

This EPA document, which happens to contain the same photo I used in the above post of an oil storage tank, was produced to explain to oil producers that they could make money capturing methane that emanates from their recently produced oil.  Here is a screenshot from the presentation:

They get a payback in this case in 4 months.  BP announced they were taking global warming as serious as far back as 1997 and started making money limiting methane emissions.  American companies, most notably Exxon-Mobil, thought they could do better by keeping up their effort to stop all possibility of being ever forced to control emissions like this by influencing the political process.  I guess the Exxon-Mobil idea is that capital spent producing more product would make even more money than the piddly 4 month paybacks they could get by limiting in any way the damage their product will inflict on their grandchildren. 

The key seems to be:  do you believe?  Do you believe greenhouse gases are a problem?  This industry, no matter what its apologists tell us, clearly, without doubt, do not.  They’ve blocked political action that would force them to make money.  Its perverse. 



David Lewis's picture
David Lewis on Dec 1, 2010

I’ve corresponded with one climate expert at an NGO:  i.e. Saya Ktiasei, who is the co-author of “The Role of Natural Gas in a Low-Carbon Energy Economy” a WorldWatch Institute “Briefing Paper” which concluded that policy should be developed to encourage a rapid switch to gas from coal, because they feel gas is so much lower in climate impact than coal.  WorldWatch has been around forever. 

Saya had previously expressed the same opinion as, I think it was David Hone on your panel, who said the preliminary paper posted online some months ago by Dr. Howarth was not “impressive”. For that matter, Howarth himself said that original work wasn’t impressive – he’s saying what he has now is ready for a peer reviewed journal. 

Saya has read this post on the state of Howarth’s work right now but she has not commented so far. 

I suggested to Saya that at minimum the NGOs must attempt to force the industry to eliminate methane leaks or they will withdraw their what has been wholehearted support of gas. NGO policy isn’t determined this way however. Flavin seems to run the place. The whole constellation of NGOs somehow figures out what is what in a way that I find unfathomable.  There is a lot of momentum behind gas.  The NGOs don’t want nuclear, and they don’t want coal with carbon capture, no matter what, even though both are certain to have lower CO2e than gas.  What other highly scalable cost effective baseload option is there?  They wouldn’t be backing gas now if they knew cost effective solar thermal with storage (i.e. baseload) would pan out.  They don’t have anything but gas, so its going to take a lot more than a Dr. Howarth to change this. 

If you add Shindell’s 30% to the impact of methane emissions that result from the use of natural gas, if they are as low as the DOE suggests (less than 1% from the US industry), it doesn’t amount to much of an addition to the CO2e for gas. 

For instance, there is this DOE National Energy Technology Laboratory (NETL) report, which claims to be the “first” good examination of the lifecycle GHG emissions of gas (published Sept 30 2010):

It appears to accept that the gas industry only loses less than 1% of its natural gas to the atmosphere while handling it.  It accepts the IPCC AR4 GWP for methane.  Methane emissions in that case have not much impact – CO2 emitted when gas is burned is the predominant factor. Adding 30% to the power of methane in this NETL analysis seems to add 3% max to the CO2e.  This isn’t going to be linear.  Howarth isn’t the only one who says if there are methane leaks beyond 2% gas is getting bad.  At 5% leaks Howarth says gas is worse than coal viewed over 100 years. 

The question is, how much methane leaks out?  I think it was Hone again who stated there are “zero” leaks in the EU.  This just seems to be denial.  The publication date on the NETL study i.e. Sept 2010, and their claim to be the “first” really hard look at gas shows how little attention has been paid to this issue. 

This talk about gas as a “destination fuel” seems right out of Alice in Wonderland.  Hone wrote a post about a conference in Qatar where they were talking like this. People seem to think the physical laws governing the behaviour of the planetary system are some interest group they can fob off with promises that someone else will do something in 50 years. 

They’re going to have to think about how to capture all the methane leaks, and how to capture ALL the CO2 if they are going to talk gas as a “destination” fuel.  NETL examined scenarios where you apply 90% capture to gas plants and at best you get 70% lifecycle reductions out of it.  The official US target of 83% reduction of CO2 by 2050 isn’t even going to stabilize the composition of the atmosphere, if all other countries matched the then per capita US emission rate.  And the electricity generation sector seems very easy to get emissions out of compared to others, such as transport. 

I’m with Bill Gates on this.  He says, “is that what we have in mind: to delay Armageddon for three years?”  The target has to be stabilizing the composition of the atmosphere.  What is becoming apparent is that the scientific community lacks confidence that the composition CAN be stabilized once the 2 degree C threshold (“dangerous climate change”) is crossed.  There isn’t a lot of confidence that the 2 degree threshold can be avoided if 450 ppm is exceeded.  And we’ve already passed what Hansen says has been the long term boundary between an ice free planet and this one, 350 ppm, if civilization leaves it all in there too long, and twenty years have gone by already.  And we’re supposed to be polite to the people who tell us this is a worldwide conspiracy of climate scientists who make up these alarming fairy tales so we’ll give them more grants. 


David Lewis's picture
David Lewis on Dec 12, 2010

Hayhoe, lead author of what Howarth calls “one of the only other peer-reviewed papers out there”, on this topic, i.e. Hayhoe K., Kheshgi HS, Jain AK, Wuebbles DJ (2002) Substitution of Natural Gas for Coal:  Climatic Effects of utility sector emissions Climatic Change 54: 107-139, knows what she is talking about

I’d be interested in seeing the type of analysis done in her paper updated with current data on aerosols and methane leakage.  Perhaps Howarth’s paper will be as good as hers. We need authoritative analysis. 

Although her 2002 paper mentions methane (CH4) emissions as a factor they considered, the conclusion was that bigger factors were, as listed in the conclusion of the abstract  “(1) SO2 emissions… and (2) the relative efficiencies of the power plants involved”.  SO2 is a big factor because it comes out of a coal plant smokestack along with the CO2 and its effect counteracts that of CO2.  You can look at it as causing coal to have less climate impact but there is a big catch.  Because CO2 lasts so much longer in the atmosphere the SO2 is enabling civilization to put that much more CO2 into the atmosphere before we notice the effects.  Whatever.  Hayhoe in 2002 assumed that methane leaks were very much less than what remote sensing technologies and a fresh look at the situation show. 

Hayhoe 2002 states clearly that the biggest methane loss factor considered as reasonable by their group was derived from the EPA/GRI study EPA itself now dismisses

Although her point on the much longer lifetime of CO2 is valid – that NAS study indicating persistent effects over millenia is a sobering view – it matters how strong the forces driving climate disruption over 50 or 100 years are, as what many fear are the positive feedbacks known to be lurking in the planetary system.

I’m not sure what her point is on the “the stone age didn’t end because we ran out of stones” thing.  Hansen discusses what the possibilities are if this fossil fuel age runs out because we run out of fossil fuel in his Bjerknes Lecture dated 2008.  Hansen says he feels it is a “dead certainty” the the oceans will boil away and Earth will never have life again if civilization is so foolish as to attempt to try to use all the fossil fuels without stopping their emissions, i.e. without actually stabilizing the composition of the atmosphere. 

The gas “resource” is collosal, if you look at the clathrates.  The same people who insist we face economic catastrophe if we stop using fossil fuels before they run out because the poor economy is so fragile it can’t stand the shock insist that when current “reserves” as opposed to the titanic sized “resource” actually do run out and there is no choice why the miracle of the capitalist system will kick in and magically produce enough energy to power exponential growth forever.  This is a standard economists line.  These people are held in high esteem. 

My view?  “We need to be realistic”, before the “natural gas vs coal debate” becomes “moot”, which is why the gas vrs coal debate has importance. The big thing is to accept that we need to stabilize the composition of the atmosphere, the next big thing is to accept that the level is far lower than most assume – the rest is details. 

If gas, the way the US is using it now, will have a similar (85-115%) climate impact as coal over even as short a period as 50 years, and if it has had, because of the way it was used in the past, a greater effect than coal if analysed over 100 years, this idea that gas is in any way “green” needs to be discarded quickly to enable clear thinking about what “realistic” alternatives are.  

Hayhoe’s comment mentions “renewable” enery sources.  Most using that term exclude nuclear, whereas they include gas fired backup to solar calling it low carbon.  What we know now about energy and climate demands that civilization take another look at nuclear, especially here in the US. 


David Lewis's picture
David Lewis on Dec 12, 2010

This observation you make, i.e. what will it be like in the former USSR, is the foundation of my point that the overall historic use of gas worldwide up to now must have been worse for climate than the impact of coal if viewed over the 100 year time frame. 

The General Accountability Office assessed US and World gas loss in 2004 and cited World Bank Data which said 3% of worldwide production was lost, “enough to meet the natural gas needs of France and Germany”.  GAO noted that EIA at that time said 0.4% of US gas production was lost.  They said data, although “incomplete”, “inconsistent”, and “limited” in the US, was way worse, “even more limited”, outside the US. “No single organization is responsible for collecting and reporting”, countries report “voluntarily”, “few countries report meaningful data”, Russia reports it doesn not flare or vent while satelllites NOAA runs measure “significant flaring” there.  Its a joke.  So if the US is actually losing 4-5% now, and was actually losing more, up to 10% at that time, what was the world losing? 


Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »