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    Blowing Hot Air: The Methane Hydrate Delusion
    By Holly Moeller | May 10th 2012 12:30 AM | 21 comments | Print | E-mail | Track Comments
    About Holly

    I'm a graduate student in Ecology and Evolution at Stanford University, where I study ecosystem metabolics and function. In particular, I'm interested...

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    Last week, word came from Prudhoe Bay that sent chills through me as surely as if I’d been standing in the Alaskan North Slope drilling outpost myself. The United States Department of Energy – in collaboration with energy giant ConocoPhillips and the Japanese nationalized minerals corporation – reported success from a month-long test extraction of methane gas tucked into an icy lattice below the permafrost.

    These methane hydrates – also called methane clathrates, after the particular crystalline structure of the ice matrix – are found in cold regions (like the Arctic, where low temperatures keep the permafrost soil layer frozen year-round) and off continental shelves (where pressure from a thick blanket of water stabilizes the compressed gas).

    Though testing to reveal the full extent and nature of these gas deposits has only just begun, methane hydrates are already making headlines as the next big energy source.

    The US Geological Survey estimates that there’s twice as much burnable carbon hiding in hydrates as in all other known fossil fuel deposits worldwide. And since methane gas burns hot and clean – giving off 33% more energy per carbon dioxide molecule emitted as petroleum, without the nasty nitrogen and sulfur oxides that come from coal – ears around the world have perked up.

    In 2006, China pledged $100 million to hydrate exploration. In 2008, Japan and Canada completed a six-day test drill in the Mackenzie Basin. And now that this year’s test results are looking good, Secretary of Energy Steven Chu says that domestic gas prices could drop 30% by 2025.

    As an added bonus, methane extraction traps CO2. The latest technology pumps the most notorious greenhouse gas into the ground, where it replaces methane in the ice matrix. The displaced methane is then pumped to the surface and – in the DoE’s (and, undoubtedly, ConocoPhillips’) vision – down pipelines to heat homes in the Lower 48.

    Plus, argue supporters, climate change projections indicate that rising temperatures may release much of that methane anyway. If the permafrost thaws or the ocean warms, vast tracts of icy clathrates could melt, outgassing methane – which has 20 times the warming potential of CO2 – into the atmosphere, further accelerating climate change. This is one of the most feared positive feedback loops known to climate scientists.

    So wouldn’t it be nice if we could turn some of that methane into carbon dioxide ahead of time?

    I don’t think so.

    Burning fossil fuels – oil, coal, and natural gas – put us into our tenuous climatic position in the first place. Any CO2 we sequester during methane hydrate extraction will quickly be replaced through burning of the extracted methane. And the CO2 trap is only temporary: warmer polar temperatures will free it as surely as the presently trapped methane scientists are so concerned about. 

    Add to this the issue of scale. Given that commercialization of methane hydrate extraction is still a political pipe dream, we’re unlikely to process any significant portion of the 320 quadrillion cubic feet of methane scattered in hydrates around the country.

    Now to don our economic hats. Increased supply and decreased costs only drive up demand. Say we can, as the DoE promises, double our natural gas supply and effect dramatic price cuts by using only 1% of domestically available methane hydrates. This quick fix of another carbon-based fuel will only delay our ultimate sustainability reckoning.

    Methane hydrates, no matter how vast their supply seems, are just another nonrenewable resource. A boom in gas production will add years – maybe decades – to the difficult but necessary transition to renewable energy sources. And in the meantime, we’ll be doing plenty of damage to our environment both globally – through additional greenhouse gas emissions – and locally – by drilling in sensitive ecosystems.

    In the last decade, we’ve fought plenty of environmental battles over how and where to drill for oil. We’ve seen the consequences – Deepwater Horizon and the Gulf of Mexico 2010 spill, for example – of pushing our technological limits towards harder and harder to reach deposits.

    And now we want to grasp at something even more risky, at mineral formations that, when destabilized, cause explosions and landslides.

    I’m afraid that the laws of economics – especially in a country that will invest $6.5 million this year alone (plus an additional $5 million, pending Congressional approval) on methane hydrate recover research – will once again favor Sarah Palin’s mantra, “Drill, baby, drill.”  Because as surely as methane is trapped within its lattice of ice, we’ve trapped ourselves in a spiderweb of fossil fuel dependency. Unlike methane, however, it seems even climate change can’t force us out.

    Front page image credit: Shutterstock

    Comments

    Halliday
    Holly:

    You say (emphasis added):

    ... since methane gas burns hot and clean – giving off 33% more energy per carbon dioxide molecule emitted as petroleum, without the nasty nitrogen and sulfur oxides that come from coal – ears around the world have perked up.

    Where do you think the nitrogen oxides come from when burning coal or petroleum?  (The other emphasized word in your quote is a hint, though only a hint.)

    David

    hollyvm
    David-- good point, and something I obviously didn't think carefully about when I drafted this.

    What David alludes to is that, especially during very hot combustion reactions, dinitrogen gas from the air may react with oxygen to form NOx gases. So the formation of nitrous and nitric oxide is not necessarily prevented by burning methane.

    My emphasis when I wrote the piece was on nitrogen- and sulfur-containing contaminants present in the coal, etc., being burned, which would not be present in pure methane gas.

    Nice catch! Thanks!
    Halliday
    Holly:

    You got it on the first try.  ;)

    Yes, I recognized that your "emphasis when [you] wrote the piece was on nitrogen- and sulfur-containing contaminants present in the coal, etc., being burned, which would not be present in pure methane gas."  Unfortunately, in the case of oxides of nitrogen, the nitrogen "containing contaminants present in the coal, etc., being burned" is a miniscule, absolutely negligible contribution.

    This is why burning hydrogen suffers from a similar pollution issue.

    By the way, do you know the greenhouse gas equivalency of various oxides of nitrogen?

    David

    P.S.  The greenhouse gas equivalency of water is also important, especially above the troposphere, where it cycles quite slowly.

    hollyvm
    Most nitrogen oxides don't have bond lengths appropriate to trapping incoming solar radiation, so their contributions to global warming are negligible. Nitrous oxide is the molecule that's the most problematic: people usually ballpark it at around 300x more potent a greenhouse gas than CO2. I really love the EPA's equivalency calculator here: http://www.epa.gov/cleanenergy/energy-resources/calculator.html
    Because of lower combustion temperatures associated with use of CH4 in power plants (as compared to coal) there is less NOx produced from the air itself, about one third.
    Halliday
    Enrico:

    Yes, NOx production from combustion, using air, depends very strongly on temperature (due to the endothermic character of this reaction).  In fact, as you probably know, it depends so strongly that even small hot spots within the combustion zone can dominate the NOx production rate.

    Now, I'm not certain, but I thought that some of the higher efficiency natural gas fired power plants use higher temperatures than coal fired power plants.  After all, thermodynamic efficiency, even for turbines, increases with increasing temperature.

    Of course, due to the strong temperature dependence of NOx production, good burner design can allow for lower NOx production even as average temperature increases, from one design to another (going toward "low NOx" burner designs).

    So, unfortunately, the "state of the art" is an ever moving thing, and I'm not completely up on the state of this art.

    David

    vongehr
    Especially regarding your comment above about that even when burning hydrogen there is this temperature/NOx issue, I suppose the state of the art (not on the streets but on the research front) is to stop all this crazy stone age like burning with hot flames and instead let the oxidation occur on nano-fabricated compound catalysts in things like formic acid fuel cells.
    Halliday
    Sascha:

    I most certainly agree about the need for us "to stop all this crazy stone age like burning with hot flames".  :)

    In fact, I have felt like we have needed to get away from (as in ween ourselves off of) combustion energy sources ever since about the '70s.  But, alas, no such good sense.  :{

    In fact, other than the transportation sector, and, perhaps, a few other areas (certainly almost all non-portable energy needs), I have felt like we have needed to ween ourselves off chemical energy sources—so little energy for so much "stuff" (fuel, etc.).  But, alas, no such sense there either.  :(

    Yes, I've been watching fuel cell tech. for about a decade, now.  Where I work, we even looked into the use of small hydrogen fuel cells, with the hydrogen stored in mettle matrices of whatever kind we could find that would work reasonably well, as a supplemental energy source for our more remote monitoring sites.  Unfortunately, it was not sufficiently reliable, at the time.  :/

    David

    vongehr
    With clathrates becoming available, it is now time to look into low-T methane fuel cells like these. We now make Pd/Pt-on-dielectric bimetallic compound nano-catalysts that outperform Pd black (at a fraction of the cost) and are not poisoned like Pt, but we have not bothered to look into what they do to methane.
    Halliday
    Sascha:

    Very nice.  :)

    Of course, as I'm sure you know, another important aspect is the dialectric that separates the air/oxygen side from the fuel side.  The fuel cells you linked to use a thin-film solid-oxide, so it is a (reasonably) good oxygen ion transport dialectric, as opposed to the proton transport dialectrics of hydrogen fuel cells.  With oxygen ion transport, as I'm certain you are aware, one has far greater fuel flexibility.

    It looks like we are getting the technology in line, little by little.  Of course, that's typically how science and technology progress.

    I look forward to being able to see society ween itself off combustion energy technologies.  :)

    David

    Thor Russell
    Yes it would be nice, but will it ever be possible for air transport, and I don't think you are suggesting we go nuclear for that. Will a fuel cell ever be able to produce enough power for its size/weight to power a passenger jet? 
    Thor Russell
    Halliday
    Thor:

    You are correct that, at this time, using fuel cells doesn't look like a solution for air travel.  However, we are far from having fuel cell solutions for a many more issues than just air transport.

    The fact is that at just about any point in aviation history there have been technologies, and/or achievements that have appeared impractical or even impossible; but were nonetheless subsequently realized.  Will fuel cell powered aircraft be among them?  I don't know, at this time.  The technology is too immature.

    David

    The 1/3 figure is from the EPA.
    Halliday
    Enrico:

    Was that an average over the different fuel sectors, or new vs. new?  (Of course, there haven't been many new coal fired plants proposed, of late, and even many of the earlier ones that were permitted haven't been built, and will not be built so long as natural gas is so inexpensive.  So cheep natural gas does have its benefit.  [Coal has other detrimental affects, besides just NOx, SO2, and such.  The ash is horrid stuff.])

    David

    Thor Russell
    How is methane extraction going to trap enough CO2? I mean unless the hydrate is burnt onsite then where does the CO2 come from, and does all of it get re-injected or just some of it. If it is burnt onsite then you use it to generate electricity so you would have to build power plants in difficult sites and long power lines?
    Thor Russell
    hollyvm
    Thor, in the recent DOE, et al., test, they actually trucked (and shipped) in tanks of CO2. So you're correct: this is not the carbon dioxide produced by burning the methane gas that's recovered (though, in a higher throughput system that has an on-site electricity generator, as you describe, it could be). As I'm sure many of us recognize, the fact that you have to transport tanks of CO2 only adds to the carbon footprint (because fuel is burned during transportation) of the process. It certainly doesn't seem like it is going to be a carbon-zero thing.
    Thor Russell
    Hmm, don't think putting the CO2 back will happen in most cases if this business gets going. They will probably do what I am told the "clean" coal does, quote the carbon footprint with sequestration when talking about environmental impacts, but for the business case use costs assuming the situation where it is not.
    Thor Russell
    Holly's premise tha the preventing of greenhouse gases is a known improvemnt to earth's inhabitants
    I don't think this is so; as what is the ideal temp of earth, what is ideal amount of CO2
    Most who are in favor of similar premises state the ideals are some where in line with pre-industrial era
    But that is a large presumption
    The cost of CO2 sequestration is huge, yet the cost/benefit is very incomplete
    The cost/benefit of other means of lowering or even just slowing the temp increase are also incomplete

    And in the meantime, we’ll be doing plenty of damage to our environment both globally – through additional greenhouse gas emissions – and locally – by drilling in sensitive ecosystems.

    The author notes that the economics favor extracting future large-scale methane extraction from below permafrost and from continental shelves. I think that remains yet to be seen but let's assume that is the case. But where is the argument that switching to renewable energy sources prematurely would be the better course of action? The unstated assumption is that solar, wind, etc. are "clean" sources of energy -- non-harmful to the environment. I doubt that is the case even now; how much worse will the environmental impact be when these sources of energy generation are scaled up by a factor of ten or thirty?

    And how bad will the financial impact be on the indigent of the world -- families that can hardly afford their electrical bill even today, even in developed nations? If the answer is, yet more economic redistribution imposed on the middle class, then I am afraid these proposals are poorly thought through.

    Thor Russell
    You claim that renewable sources are more environmentally harmful? Given that is not the common assumption that certainly needs backing up with some kind of argument. If you believe that 1KW of energy generated from solar is more harmful than from methane then show some evidence. You are also making the assumption that the environmental impact of 1KW of renewables will INCREASE with scale. This is very unlikely and the evidence is strongly against it. With economies of scale, the energy, (EROI) resources and environmental impact of solar has been dropping so the environmental impact per KW which is the sensible measure will get better. 
    You are also out of touch with the financial impact in developing countries. In many places in the 3rd world not connected to the grid, renewables are either the cheapest or the only way to get electricity. That is only going to get better as renewables are expanded and continue along their cost reduction curve. Even where there is a grid, solar is now cheaper than diesel generated electricity in developing countries, making these exact families lives better. Like many people you are not up with how the massive drop in price in solar lately has changed much of the picture. There is no reason for that trend not to continue also.

    Thor Russell
    Sorry, the first paragraph above was supposed to show in italics, being a verbatim quote from the author's article.