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Worse than Coal?

As I noted in last Wednesday’s posting, one of the questions that came up in a webinar on shale gas in which I participated concerned the climate consequences of higher recent estimates of methane leakage from US natural gas systems. In reading further comments and blog postings on this subject, I was surprised to see assertions that went beyond drawing attention to the importance of the leakage of a high-value, high global-warming-impact gas, to suggest that the apparent rate of leakage renders the lifecycle emissions from natural gas as bad as those from coal, or worse. If that were true, it would have significant implications not only for the development of shale and other natural gas resources, but also for our entire emissions reduction strategy. From what I can tell, however, such claims have not been substantiated by current studies.

Several comments I received in email or on the posting pointed to the work of Professor Robert Howarth of Cornell University, and specifically to a press release describing a paper he has apparently submitted addressing the climate impact of methane leaks from shale gas production, transportation and storage. Until the details of the paper are available, the information provided in the press release simply doesn’t stand on its own or merit further analysis. In the meantime, a recent EPA report evaluating greenhouse gas emissions from the oil and gas industry identifies significantly higher estimates for methane emissions from natural gas systems than those incorporated into that agency’s most recent US Greenhouse Gas Inventory. I became aware of the EPA report in the course of reading one of the blog postings I alluded to above.

The EPA estimated the total CO2-equivalent methane leakage from the production, processing, transportation, storage and distribution of natural gas in the US in 2006 at 261 million tons per year. That amounts to more than 4% of total net US emissions for that year, so it is hardly insignificant. It’s also about 2.5 times the figure reported in the agency’s latest GHG inventory. Converting that quantity back into natural gas at normal conditions yields 656 billion cubic feet of gas, or 3.4% of marketed US natural gas production in 2006. That’s a lot higher than typical leakage estimates of less than 1%, as David Lewis notes in his blog. The question is whether this higher level of leaks, or some even higher notional level of leaks proposed by other critics, would be sufficient to make the emissions from gas worse than those from coal.

To understand why that might even be possible, you have to know something about the relative strength of different greenhouse gases (GHGs). While much of the public’s attention has been focused on CO2, the most prevalent man-made GHG, other gases have dozens or hundreds of times the impact on climate, per ton. Because of the way it decays in the atmosphere, methane’s global warming potential (GWP) starts high and diminishes over longer time spans. Most reports, including the EPA’s, use a 100-year GWP estimate indicating methane is around 21 times worse than CO2.

However, it’s not correct to infer from that that upstream leaks of 3.4% of all natural gas must therefore inflate the lifecycle emissions of the gas we consume by 21 times 3.4%, or 71%. That’s because a ton of methane doesn’t convert to a ton of CO2 when burned; it yields 2.75 tons, as a result of basic high school chemistry:

CH4 + 2O2 –> CO2 + 2H20

So for each ton of natural gas, it’s roughly 7.6 time worse for it to be vented or leaked than burned, after adjusting methane’s standard GWP for the ratio of molecular weights from the above reaction equation. In fact, when I added the EPA’s latest methane emissions estimates to their figures for indirect and direct CO2 emissions from natural gas in the GHG inventory, the result was very close to the 26% increase you’d get from multiplying 3.4% by 7.6. As a result, although the emissions advantage of natural gas over coal is less than it would be without such a high rate of leakage, gas still emits 35% less CO2 equivalent per BTU over its lifecycle than coal, on average.

When you consider how natural gas actually competes with coal, its effective emissions advantage should be larger than that. Even after accounting for upstream emissions (including leakage) that add 30% to its CO2 emissions from combustion, an efficient combined-cycle power plant still generates electricity with emissions per kilowatt-hour that are more than 40% lower than those from a highly-efficient coal plant. That’s because the combined cycle turbine converts more than half the BTUs in its fuel into electricity, while the coal plant converts less than 40% of coal’s BTUs into power. Fewer BTUs for the same output results in fewer emissions.

I don’t claim my back-of-the-envelope analysis is definitive, but it certainly doesn’t support the notion that gas is worse than coal. Barring conclusive evidence of a much higher level of upstream natural gas leakage than indicated by the EPA’s latest work on the subject, natural gas–even with existing infrastructure–could reduce the emissions associated with coal use in power generation by at least a third, and by much more than that depending on the specific generating facilities involved. At the same time, that shouldn’t be read as excusing avoidable leaks of gas. If that 3% figure is accurate or low, then several billion dollars worth of gas–even at today’s depressed prices–is escaping into the atmosphere rather than being captured and turned into useful energy by gas customers. That sounds like the epitome of low-hanging fruit to me.

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Rick Engebretson's picture
Rick Engebretson on Dec 9, 2010

My wife and I attended a Minnesota Orchestra concert of Handel’s Messiah, yesterday. And John Lennon was remembered on the news.

No matter what some do or say, others will try bash it. Few can offer anything better. As our economy and environment remain hard pressed, you are very right for pointing out the very positive events concerning methane. The critics do get to a person, but let’s try stay positive. (Yeah, I know, take my own advice.)

Rick Engebretson's picture
Rick Engebretson on Dec 9, 2010

Nuclear fission is the process of multiplying radioactive waste. When the nuclear industry can handle their own waste they might have a process that isn’t leading us backwards from sustainability.

Methane is a natural, recycled hydride of carbon. Certainly, extraction from difficult mineral deposits and transport of the resource requires caution. But the industry is the foundation of our energy infrastructure and deserves praise for their performance.

Methane is a good hydrogen carrier, and leads us toward greater hydrogen energy and non-energy solutions.

Charles Barton's picture
Charles Barton on Dec 9, 2010

Geoff, The natural gas industry faces an old and deteriorating infrastructure.  The infrastructure is huge.  There is something like 360,000 miles of gas lines in Texas.  One recent estimate that over three million NG compressors were defective and either leaked or was pronned to leakage.  The problems are manifested in the increasing number of homes that blow up every year due to natural gas explosions. 

In addition to NG leaks, inefficient combustion leads to methane relesses.  This problem is rarely mentioned, it effects not only home and commercial use of gas, but the inefficient combistion of natural gas by power generationfacilities.  Shifting power output, leads to inefficient combustion in natural gas fired generation facilites, and acting as wind and solar backup are arguably a major source inefficient combustion innatural gas turbines.  The truth is that no one is doing comprehensive research on methane emissions, and the natural gas producers are sweeping the problem under the rug, while hoping no one will notice how many homes, pipelines and natural gas powered electrcal plants are blowing up, ant how much methane is escaping into the atmosphere. 

Is NG a worse greenhouse gas problem than coal?  We don’t know enough to really say, thus it is possible that the answer is yes.  At any rate, even with the most optomistic assumptions, natural gas is part of the Green house gas problem, not its solution.   It should also be pointed out that the natural gas industry has been attempting to sell its product as a clean energy solution, while at the same time hiding exactly how dirty that product is.  It should be the job of the media in general and the energy collective in particular to uncover the dishonest parts of the natural gas story, and expose them for all to know. 

Geoffrey Styles's picture
Geoffrey Styles on Dec 9, 2010

Charles, what’s your alternative for the 24% of our energy we get from gas, which includes significant use of gas as a feedstock for key chemicals?  I’m sure you wouldn’t suggest shutting down many of the nation’s 104 nuclear power plants because they, too, are getting old–half built in the 1960s or 70s. (Nor would I.)  If there’s a problem, let’s fix it. 

Geoffrey Styles's picture
Geoffrey Styles on Dec 9, 2010

It’s all down to the trade-offs we’re willing to make.  We may not like any of the choices, but we can’t say no to everything.

Geoffrey Styles's picture
Geoffrey Styles on Dec 9, 2010

Erik,

Thanks for those observations.  Obviously I don’t agree that I “undermined my analysis” by using the same GWP of 21 as the EPA.  Please feel free to redo my calculations with a GWP of either 25 or 33, and you’ll see that although it narrows the gap between gas and coal slightly it doesn’t close it, particularly after considering the efficiency difference between CCGT and coal-fired generation.  Using a GWP of 33 and assuming the 3.4% leakage rate gas-fired generation still ends up with emissions more than a third lower than best-in-class coal.  As for the 20-year vs. 100-year time-frame, if I were convinced the entire energy transition under discussion could be competed within 20 years you’d find me easier to persuade that the 20-year GWP is the appropriate one to use.

With regard to uncertainty, in my professional experience it’s something to be managed but not used as an excuse for inaction or for choosing impractical alternatives.  The answer to the uncertainty about the magnitude of those leaks it to tackle them, not throw our hands in the air. 

As for Howarth’s work, I wasn’t being flippant.  I was merely reflecting that a press release isn’t a published paper, and the press release in question is built around a graph that lacks a clear indication of its scale, let alone an explanation of the basis on which the various components of the bars for each category were calculated. (The proportions of the “coal-best technology” category relative to the undefined natural gas bar are notably suspect.) There’s simply not enough information to assess its accuracy, and without the key details anyone taking it at face value is on thin ice. 

You won’t see me calling natural gas “green”, although clean isn’t such a stretch, particularly after considering its local pollutant impact compared to other fuels.  Yes, it’s still a fossil fuel, and it still emits orders of magnitude more GHG than nuclear, wind or solar.  Having said that, I remain unconvinced–not as a matter of opinion, but because the numbers don’t support the conclusion–that it’s worse than coal and shouldn’t be a key part of our near-to-medium term playbook for reducing emissions.

Geoffrey Styles's picture
Geoffrey Styles on Dec 9, 2010

We agree on the goal, but we seem to be miles apart on the likely timing.

Rick Engebretson's picture
Rick Engebretson on Dec 9, 2010

(re: Geoff)”You won’t see me calling natural gas “green”, although clean isn’t such a stretch. (and) Yes, it’s still a fossil fuel.”

About 23 years ago I submitted a proposal to recycle plastic and mass produce a livestock septic tank. It was an adaptation of a steel tank system and the proposal was intended to find a use for waste plastic (blue and red recycled plastic would make a pink tank.). The head of the state Ag. group then informed me methane was a greenhouse gas (I didn’t know about the issue, I just wanted healtier farms and plastic recycling) that could be seen from NASA satellites over large feedlots, especially Australia. Then about 10 years ago our utility bragged about their concrete version and I was introduced to the head of the US REA. There is a lot of methane just from livestock waste. So it can be green and it need not be fossil. And there is serious interest.

The problem is capital investment. People properly want cheap fuel and food so capital investment takes a back seat. We had a bridge collapse in Minneapolis for the same reason. Many are working VERY hard to move forward. Another academic study is fine, but we need sweat and time.

 

Nathan Wilson's picture
Nathan Wilson on Dec 10, 2010

Rick, nuclear fission is also a natural process, and radiation is a part of the natural environment (it comes from the Earth and sky). 

Your attempt to analyze our energy choices using natural philosophy is a bit off the mark.  The defining feature of all living things is that they take energy and material from their environment, use them for their own purposes, and then expel the waste.  The unique twist that we modern humans have come up with is that we can draw upon resources like mined metals and fossil fuels that lie beyond the limits of the biosphere; resulting from our use of science and engineering.  This clearly has produced enormous benefits for our quality of life; instead of all being farmers or hunters, we can choose to be other things, like doctors, engineers, or artists.  

The next logical step in our development is that we must again apply good science engineering to preserve the Earth and use its resources and dispose of our waste in a sustainable fashion.  This means using plentiful materials like iron and uranium; in some cases this will mean disposing of some of our waste beyond the biosphere.  Because nuclear waste is thousands to millions of times more compact than other wastes, we can affordably put it outside of the biosphere.

To do this very important job, we must be guided by science, and not superstition.  So if you want to determine whether “natural” gas use (or a combination of gas and renewables) is better for the environment than use of natural nuclear materials for power, you’d better be prepared to do some science in your evaluation.  As you can see in Geoffrey’s article, environmental impact assessment is a complex business.

The fact that we have not begun permanently disposing of nuclear waste (which belongs to us, not the nuclear industry, just as the sun does not belong to the solar industry) is a result of three reasons:

  1. We as a people would rather argue about it instead.  Its a football to be tossed around for fun.
  2. There is no immediate need.  Because it is so compact, 40 or 400 years worth really takes up hardly any space at all.  And it’s easy to store safely: it’s solid, so it stays where we put it.
  3. Its bad engineering to rush and put that stuff in the ground before it has a chance to cool.  Those radioactive materials that some find so frightening have their own time tables.  The more it cools, the more tightly you can pack it into a repository.

Lastly, as had been said many times before, hydrogen is not an energy source, merely a carrier.  It is much worse of an instant carrier than electricity, and much worse of a storage carrier than lifted water or solar salt.  In engineering, we don’t change the laws of physics to please the customer; we have to use what we have.

Science is humanity’s most successful method of predicting the future.  Get over it.

Rick Engebretson's picture
Rick Engebretson on Dec 10, 2010

Nathan, you have me all wrong.

My undergrad degree was neurophysiology, it was suggested I try Biophysics grad school under Otto Schmitt who invented digital electronics by copying nerve electronics (I’m sitting at his old desk right now). Along the way I was the only one to succeed at top genetics, biochemistry, and physics. My Ph.D. work involved tritium exchange kinetics of proteins at record pressures. But the thesis title was constructed by the research department at the world’s first supercomputer company, Control Data Corp. “Protein as Dynamically Reconfigurable Liquid Crystal Microprocessors,” described how acids and bases on protein in water are the equivalent of an addressing mechanism in semiconductors (water is a semiconductor and a hydrogen nuclei is just a proton: not trivial energy science). I’ve seen more science shape more future than most.

If you don’t understand my motives, just ask. But don’t insult my skills. And if cleaning up nuclear waste is so easy, it would be a good step toward greater public confidence.

Rick Engebretson's picture
Rick Engebretson on Dec 10, 2010

Nathan, just to clarify my position. I am far more concerned about farm waste than nuclear waste.

Radiation usually causes “point mutations” in genetics. The micobes growing in farm waste are not contained, and can cause far more serious mutations. Much has been said about antibiotic resistance and pandemic flus. But cancers can also be caused by microbes. So I attempt to present an opportunity to manage farm waste better.

But I don’t blame most farmers any more than I blame nuclear engineers. The working stiffs of this country are stretching every dollar and minute. I don’t understand all the unemployment when there is so much to do. So farmers should not be competing with nuclear engineers for the 30cents on the dollar. We need the other 70cents on the dollar actually used for energy infrastructure improvements.

Charles Barton's picture
Charles Barton on Dec 10, 2010

Ed, the problem is with compressor couplings:

http://www.wfaa.com/news/local/Natural-Gas-Blamed-in-Irving-House-Explos...

“Atmos Energy declined an on-camera interview with News 8, but issued this written statement:
“Safety is our number one priority. We have checked out the area to make sure it is safe and are working with the city and state to investigate the cause.”

It’s similar to the statement Atmos issued after a house explosion in Mesquite last November. Kristi Samons was at home at the time and survived the gas explosion, which Atmos first blamed on carbon monoxide.

The official preliminary cause of that blast was judged to be a leaking compression coupling on the Atmos gas line.  For days afterward, gas leaks were discovered all over the Mesquite neighborhood.

Much like the situation in Mesquite just a couple of months ago, Atmos crews are finding more leaks in the Irving neighborhood surrounding Sunday’s blast.
In May of last year, less than a mile away from Sunday’s explosion in Irving, another house exploded. Again, it is being blamed on a leaking compression coupling on an Atmos gas line.

In Cleburne in 2007, two people died in a house explosion, which again, was blamed on a leaking compression coupling.
In Wylie in 2006, there was another house explosion. Two people died and again, a leaking compression coupling was blamed.

Following a News 8 investigation, the Texas Railroad Commission ordered the removal of faulty couplings attached to gas meters. But there are an estimated three million other compression couplings still in the ground that may be prone to leaks.”

Charles Barton's picture
Charles Barton on Dec 10, 2010

Geof, A lot more research and development investment has to go into the consequences of adopting the natural gas bridge.  The history of an earlier fossil fuel bridge to post-carbon energy is instructive.  I am referring to Amory Lovins coal bridge to soft-energy.  By Lovins account coal use should by 2010 be rapidly declining, and should end by 2020.  Needless to say this is not going to happen.  So Lovins coal bridge proved to be “a bridge to nowhere.”  When I hear abort natural gas as a bridge to soft energy by 2050, I have to wonder if this is another “bridge to nowhere.”  The story is that we will in the next few years build lots of natural gas generators, and no sooner build them than to replace them with post-carbon energy sources.  I find this two step vision less than credible.  It does not explain how adoptiong the natural gas bridge will get us to a post carbon energy world.  If we want post-carbon energy by 2050, our focuse has to be on rapid adoption of post-carbon energy technology, not on the adoption of the carbon-emitting natural gas bridge.

 

Geoffrey Styles's picture
Geoffrey Styles on Dec 10, 2010

Charles,

Reasonable people can and do disagree on this point, but for me it comes down to the math.  Coal currently generates roughly 1.9 billion MWh/yr in the US, to nuclear’s 0.8 and gas’s 0.9, hydro’s 0.3 and less than 0.2 for all non-hydro renewables combined.  (Note that oil is lost in the rounding, refuting all the eyewash about wind power reducing oil imports.)  What do we have with which to displace coal?  With Exelon’s announcement re Oyster Creek (roughly canceling out their other expansions, according to Rod’s posting yesterday), the uncertainty about Vermont Yankee, serious challenges to Indian Point’s re-licensing, and with Watts Bar 2 the only new US nuclear plant even close to commissioning, nuclear might do no better than going sideways for the next decade. Some net growth after that, but will it be enough to take a big chunk of the market away from coal?  So triple or quadruple non-hydro renewables and that still leaves the emissions from more than 1 billion MWh/yr from coal to deal with–assuming that wind and solar even compete much with coal, rather than gas.  I’m as enthusiastic about CCS as anyone, but I don’t see it making a dent in current emissions much before 2025.  There’s tremendous scope for efficiency to reduce demand, but history says there’s also at least as much chance that the gains from efficiency will be consumed by new devices, now including EVs. 

Barring nearly miraculous changes, that leaves gas as the likeliest option that can be ramped up quickly and is available at the scale needed to displace a meaningful share of our coal use.  That’s why this question of relative emissions is more than an academic exercise, and why it’s important not to overreact to unvalidated assertions about it.  I’d like to know the answer, too, but if you run the numbers, as I did, it would take one heck of a lot of unreported leaks–well beyond the EPA’s estimate–to negate all the emissions-reduction benefits of highly efficient CCGTs running at high utilization to displace current baseload coal. 

Geoffrey Styles's picture
Geoffrey Styles on Dec 10, 2010

Charles,

Compression couplings are not compressors.  Here’s a Texas Railroad Commission report on coupling failures, complete with some photos of the devices, which are a form of pipe joint. 

Geoffrey Styles's picture
Geoffrey Styles on Dec 10, 2010

Nathan,

The jury is still out on whether H2 or electrons will turn out to be the better energy carrier for transportation.  A hydrogen tank can be refilled orders of magnitude faster than a battery can be charged (at acceptable voltage & amperage), but battery-swapping schemes could finesse that.  The judgment probably rests with consumers and entrepreneurs as much as with engineers and scientists. 

Rick Engebretson's picture
Rick Engebretson on Dec 10, 2010

Rod, Ya mean nuclear engineers don’t go to the coffee shop every morning with spent fuel (manure) on their boots?

Seriously, if you read my rambling posts, all I really said is if farmers used some “carefully designed, but rather simple containers” there would be a lot of new methane available. I don’t push “esoteric knowledge” unless somebody pulls an attitude on me. The fact that water is a proton semiconductor is “day to day living.”

BTW, it is fusion, not fission, that provides 98% of the energy, and we’ve heard many promises not yet met.

David Lewis's picture
David Lewis on Dec 10, 2010

As the perception of what the climate impact of gas moves from 50% that of coal towards equalling it or being worse than coal here’s how the issue may be seen by the public. 

At 50%, somehow, environmentalists have bought into gas is “green” even though the problem was crystal clear from the mid 1980s on that as civilization expanded from the 1 billion then living as North Americans do towards 8 or 10 billion living that way as we now see India and China reaching towards there would be problems powering the order of magnitude expansion of civilization with fuels such as gas that aren’t ten times better in the way of CO2 emissions. 

By the time you get to gas is only 75% as bad as coal the green color is fading fast.  No amount of bleaching by environmental leaders or industry touts is going to produce the same “green” image for gas now.  If when the dust settles the impact is greater, take a look at what even 95% looks like.  No one is going to care about arguments about how gas is a bit better than coal by then. 

David Lewis's picture
David Lewis on Dec 10, 2010

I have read, I thought in the GAO report I posted about, that inefficient combustion of flared gas is a small but non trivial source of methane emissions to the atmosphere.  Small in comparison to how large of a problem this is, non trivial in the sense if the country was taking GHG emissions seriously this source would appear to be very low hanging fruit.  

 

David Lewis's picture
David Lewis on Dec 10, 2010

Given the evidence facing civilization, continuing on with fossil fuel use is skating on thin ice.

Here’s is an example of what one professor, Euan Nisbett, believes will go a long way towards settling this type of argument – i.e. direct measurement by remote sensing equipment. 

The drawing shown is from one of Howarth’s references, i.e. Direct Measurement of Fugitive Emissions of Hydrocarbons from a Refinery, Chambers et.al, J. Air and Waste Management Association 58: 1047-1056

It scans, typically, as far as 500 m away, using a “pulsed tunable laser operating at two discrete wavelengths, one strongly absorbed by the gas species of interest and one weakly absorbed”.  The DIAL system is “unique” compared to other “open path” optical methods, as it can measure all along the path in its line of sight and does not require a target to reflect its beam as it measures backscatter.  Data “can be collected day or night in a wide range of weather conditions.”

As a result of a study done on a refinery with this, methane emissions 9 times in excess of what standard techniques involving calculations based on what type of equipment exists in the refinery were detected.  This is the kind of “thin ice” Howarth is skating on. 

Nisbet points out in his paper in Science, that in principle it is possible to directly measure national emissions by “sniffing” the air as he puts it, measuring from the top down rather than calculating from the bottom up, and he feels success in doing so is not that far away. 

This sudden realization that Big Gas was letting out many times an order of magnitude of Silent But Deadly emissions it claimed not to be aware of is going to happen to a whole load of organizations that either thought they had an idea of what they were emitting or were reporting low because they did not care. 

David Lewis's picture
David Lewis on Dec 10, 2010

Here’s how they’re doing fixing the problem.  This graph is from page 13 of GAO’s study of gas leaks.  They are doing nothing to control the leaks they have to report, the OGOR data that barely shows up compare to what EPA says they estimate, and no matter how many billion cubic feet the STAR program records as eliminated the leakage stays around the same order of magnitude.  And the product leaking is what they sell. As the price tripled for gas a number of years back it did not matter to these people they just kept on doing the same as what they’ve been doing, putting their capital into finding more gas rather than getting the most out of what they had found. 

Your position that if there’s a problem let’s fix it is not shared by most of the US oil and gas industry.  Their position is if there’s a problem let’s deny it.  The STAR program EPA runs to try to get the industry to go after the “low hanging fruit” has been running since 1993. When GAO examined this same issue in 2004 they were told by industry that 65% of the industry was on board with the STAR program. Its a joke. 

They could be making money recovering 40% of their emissions with payback periods described by GAO as measured in months.  The longest payback mentioned was two years. 

This industry risks ending up in a similar boat to what Rod Adams is talking about when he brings up the tiny leaks of radiation in buried pipes on the reactor site causing a political furore strong enough to threaten that reactor with being forced to close down. 

 

Geoffrey Styles's picture
Geoffrey Styles on Dec 10, 2010

You’ll never hear me dismiss perceptions out of hand.  They matter.  But let’s scale the problem, shall we?  The EPA reports emissions from coal in 2008 as 2.08 billion metric tons of CO2 equivalent, with 95% of it attributable to power generation.  If gas could only cut a quarter of a large portion of that instead of half, would we really turn up our noses, particularly when gas burns without producing all those other nasty things that have to be scrubbed out of the stacks of coal-fired power plants, aside from CO2?  Even if much of the notional reduction in gas’s advantage relative to coal that we’ve been debating across several of your and my postings is–as we both seem to be saying, though in different ways–not only amenable to significant improvement but comes with an intrinsic financial reward for doing so, unlike CO2 for which we have to create an artificial market first? 

We might answer that question differently, based on our experiences and worldviews, but the outcome hardly seems like a foregone conclusion to me.  And now the weekend beckons.

Geoffrey Styles's picture
Geoffrey Styles on Dec 10, 2010

At last something we can agree on: all of this is estimates at this point, and until someone actually measures what’s going on at the 479,000 plus gas wells, the processing facilities and caverns and a very large number of miles of pipelines and reticulation systems down to the “last mile”, it’s only estimates.  Maybe the latest estimates will induce someone to dedicate the budget and resources a comprehensive survey of ground truth would require.   

David Lewis's picture
David Lewis on Dec 11, 2010

Environmentalist perception of gas as “green”er than it is, coupled with the sudden realization that there is more gas in the world that is economically recoverable than was thought, leads to politics that has stalled the recently heralded nuclear renaissance, and got people talking about gas as a “destination” fuel.  I just find it all a drag to listen to.  They should call gas the “oblivion” fuel, or the “bridge” fuel to oblivion. I favor nuclear as the economical low carbon answer and just as a fantastically concentrated source of power.  “Is that what we want?”  says BIll Gates, “Three more years?”  He means one half, 75%, whatever, it isn’t going to do the job.  We need to get to as close to zero as quickly as we can.  What are we doing fooling around expanding the fossil fuel sector? 

I don’t think people who feel that the size of the fossil sector must be expanded or maintained because it is there, like Everest, will worry if gas is nearly as bad as coal or if it is worse.  Its available, it seems to be abundant with a collosal resource backing it up so why not? 

Fossil interests stopped climate action at the door of the US Senate knowing this would stall global action, at the high tide of Democratic Party power, regardless of what evidence or argument was presented. They aren’t going to worry about CH4 leaks given some GWP factor calculated over 20 or 100 years. 

David Lewis's picture
David Lewis on Dec 11, 2010

Nisbet is talking satellite observation as well. Imagine the evil doers this cooperative, productive industry, unaware that by letting off their silent but deadly blasts of methane they are endangering us all, waiting for the day when, monitored by satellite, unable to deny one more day , they start to make money, cleaning up in more ways than one. 

Nisbet says no one thought it would be possible to sign a nuclear test ban treaty until a means of detecting, at long range. nuclear bomb tests was worked out and when the idea came up there were many who thought it was impossible.  The capability was developed and the treaties were signed.  He’s been talking about and studying how to detect at long range for a long time and says things are moving along, especially on the methane front. 

I’m going to study up on what the potential is.  When he’s talking verifying national totals he’s talking about something that will be feasible, not the kind of thing that seems to be coming into your mind with the 479,000 gas wells plus associated facilities. 

David Lewis's picture
David Lewis on Dec 11, 2010

Republican Presidential contender Sarah Palin says yes indeed, she can say no to everything.  I quote:  “What’s wrong with being the party of ‘No’?”  Its inspiring. 

Charles Barton's picture
Charles Barton on Dec 11, 2010

Goef, You are right, but 3,00,000 defective couplings in Texas alone can leak a lot of methane.  Remember, the only reason we know these leaks exist, is that texas houses are blowing up as a consequence.  We can only speculate about leaks that do not lead to explosion.    The Texas Railroad Commission Report you linked to shows that the couplings problemn has long been known.  Had the word nuclear rather than natural gas been attached to the couplings, the safety hazard would have been universally regardeed as unacceptable.  But regulators, environmentalists, and the media practice a double standard with respect to nuclear power and natural gas.  If you are killed in a natural gas related accident you are far less dead, it seems, that if you are killed in an accident involving nuclear power.  Do you wonder that nuclear supporters are cynical about the professionalism and competence of journalists, and the ethincs of environmentalists?

Geoffrey Styles's picture
Geoffrey Styles on Dec 11, 2010

delete duplicate comment

Geoffrey Styles's picture
Geoffrey Styles on Dec 13, 2010

Willem,

From a quick glance the only thing I noticed that you might want to adjust was the conversion factor you’re using to go from tons of CO2e to cubic feet of methane.  It seems to be for STP, while standard cubic feet of gas are assessed at 60°F.  I’ll have a closer look next week, as time permits.

Updated Monday:

I see you’ve adjusted for the gas temp. and that all looks fine.  The surprising point in your calculations is that while CCGT reduces emissions at a lower cost than the other options you looked at, $300/ton is hardly cheap.  When I tried to figure out why, I saw two concerns: 1.  This assumes that the CCGTs are being built entirely to reduce emissions, without accounting for their lower-cost output relative to other options–at least in the absence of a price on CO2–if not necessarily versus the coal plants they’d replace.  How does the cost of power factor into the analysis?  2.  This also assumes that every MW of CCGT for displacing coal must be newbuild, rather than under-utilized existing capacity.  I know a lot of that 440 GW of existing gas-fired capacity consists of simple-cycle and peakers, but wouldn’t some degree of substitution be feasible with existing capacity at much lower cost/ton?

Geoffrey Styles's picture
Geoffrey Styles on Dec 13, 2010

Further to the discussion of the global warming potential of methane, I note with interest that the Cancun Conference (COP-16) agreed on the continued appropriateness of the 100-yr GWPs from the Fourth Assessment Review, which gives a value of 25 for methane.  Using a figure of 25 instead of 21 in the calculations on which my posting was based reduces the GHG advantage of natural gas vs. coal by only about 3%, and so does not alter its conclusions. 

Geoffrey Styles's picture

Thank Geoffrey for the Post!

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