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The Precarious Future of Coal

A new MIT report says that much more effort is needed to develop and test technology that will make clean-coal power plants economical and practical.

By Kevin Bullis

Wednesday, March 14, 2007

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Energy experts from MIT have released a long-awaited report on the future of coal. The report recommends that much more be done to develop technology for decreasing the impact of burning coal on global warming. The report also challenges some conventional thinking about the best way forward. It criticizes current efforts by the Department of Energy (DOE) and calls for an approximately $5 billion, 10-year program to demonstrate technology for capturing and storing carbon dioxide released by coal-fired power plants.

John Deutch, professor of chemistry at MIT, announces a new road map for reducing carbon emissions from coal.
Credit: Kevin Bullis

The report, based on a study by 13 MIT faculty members, comes at a time when growing concerns about global warming are making it increasingly likely that governments worldwide will impose a price on carbon-dioxide emissions to force a cut in the release of this important greenhouse gas. Nevertheless, coal, the leading source of carbon-dioxide emissions from electricity generation, will continue to be a major source of electricity, say the authors of the report. That's because even with a high price on carbon, coal is abundant and probably necessary to meet fast-growing demand for energy worldwide.

Reducing the impact of continued coal use on global warming will require a massive effort to collect carbon dioxide from power plants and bury it underground, the experts say. The volume of compressed carbon dioxide that will need to be captured and transported is similar in scale to the amount of oil consumed in the United States, the report says.

Doing so is "not simply a matter of bolting on a box to capture carbon dioxide," says John Deutch, a professor of chemistry at MIT. Indeed, retrofitting existing plants will require wholesale restructuring, even for advanced coal plants, he says. And although there are a few carbon-sequestration projects going on around the world, none of these has been put together with the sort of careful monitoring required to assure the public and energy investors that long-term, extremely high-volume carbon-dioxide storage is possible.

The report challenged the idea, argued by some energy experts, that a new type of coal plant--one that converts coal into a gas before burning it--will make it easier and cheaper to capture carbon dioxide, compared with collecting it from the smokestacks of conventional power plants. The MIT experts say that several factors make the picture more complicated. Such coal gasification doesn't work well with low-grade coal, for example, and both the new and the conventional plants will require major changes to capture carbon dioxide, according to the MIT report.

Comments

  • using up the carbon ?
    why are we not working on a TOTAL solution which
    also uses up the carbon to create MORE energy ? none of the studies are getting where we need to go !!! check out www.brienergy.com - using up the
    carbon instead of storing it underground - or are we storing it so we can come back later and do the second pass to create energy FROM it - lets do it right guys !!!
    Rate this comment: 12345

    VCRAGAIN
    03/15/2007
    Posts:35
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    4/5
    • Re: using up the carbon ?
      The problem is - we ARE using up the carbon.  CO2 is the lowest form of energy in which carbon exists, so it is not possible to extract energy from CO2.  If carbon is used as energy source, we will always end up with CO2.  Renewable processes either use an external energy source to convert the CO2 to molecules of higher energy (like photosynthesis using solar energy), or use non-carbon processes (solar energy to electricity, nuclear energy etc.)  Irrespective of where the carbon comes from, we will release CO2 from a carbon-based energy process.  If we want to minimise CO2 emissions, we must either replace the energy source, or maximise the efficiency of the total process (i.e. minimise energy losses ALL THE WAY to final use).  The latter will not reduce CO2 per se, but will maximise the amount of usable energy per molecule of CO2 created.

      Currently, the main source of CO2 use is still photosynthesis, and ideally we need to reduce the amount of CO2 released only down to the amount of CO2 that can be processed by photosynthesis (sounds easy, but in fact this is a huge challenge!)
      Rate this comment: 12345

      Daniel from ...
      01/09/2008
      Posts:8
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  • Sequestration costs
    The recent MIT report also projects carbon emissions costs (tax or sequestration) of $300-500 per ton, about $0.14 per KWH.

    The sequestration pilot project is proposed to handle one million tons of CO2, but this is only one month's output of one large coal plant.
    Rate this comment: 12345

    bobhargraves
    03/15/2007
    Posts:7
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    • Re: Sequestration costs
      The link to the report I read is
      uregina.ca/ghgt7/PDF/papers/nonpeer/139.pdf
      Rate this comment: 12345

      bobhargraves
      03/15/2007
      Posts:7
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    • Sequestration pitfalls
      We seem to be neglecting the volume issue.  Gases, even under extreme pressure occupy significantly more volume than the solids/liquids they replace.  It's still the same number of Carbon atoms.  Not to be too funny, but what happens when the ground "burps" and mass quantities are re-released?

      My money's still on bio-cycling with algae as a direct C-reduction vector back to usable oil.
      Rate this comment: 12345

      Dr. Orbis
      03/15/2007
      Posts:7
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      • Re: Sequestration pitfalls
        I agree that the fear of "burps" is a real concern.  Isn't that a chief reason to go with large-but-not-too-large tests/proof of concept, etc.?

        Obviously sequestration in some situations will likely prove safe, in other geological formations, methodologies it will be expensive of even unsafe.

        My suspicion is that a $5 billion series of pilot projects will answer some of these questions one way or another.  As well as develop the art, reduce costs, etc.

        Sequestration would surely be one of a suite of approaches finally adopted, at best. Not a magic bullet.
        Rate this comment: 12345

        Reptile
        03/21/2007
        Posts:11
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        • Re: Sequestration pitfalls
          One of the bigger concerns I know about is the long term effect of long term sequestration.  If CO2 is stored in an inert facility, fine.  But what will happen (for instance) to the pH of sea water if the sea is used as storage facility?  (Not my own question - I remember reading this concern).  Similarly, are we just leaving another problem for our children to eventually SOLVE?
          Rate this comment: 12345

          Daniel from ...
          01/09/2008
          Posts:8
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    • Re: Sequestration costs
      I am involved in driving mine shafts by freezing the soil around the shaft to form a temporary structure while a permanent structure is built.

      I am interested in carbon doxide as R-744 (a refrigerant).  At 2000 feet below ground  the pressure of a liquid column carbon dioxide is about 800 psi higher than it is on the surface and at this pressure it will not evaporate down the hole.  It should be easy and cheap to sequester liquid carbon dioxide at a depth where it will not evaporate.
      Rate this comment: 12345

      indref
      03/29/2007
      Posts:1
  • More Nukes less Kooks
    Even a founder of Greenpeace has come to understand that nuclear power is the best way to the future.
    We need more support and experience with fission
    before fusion becomes a reality.
    Rate this comment: 12345

    SirLanse
    03/15/2007
    Posts:49
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  • Best options first: efficiency, renewables
    Carbon sequestration, fission, and fusion are seductive indeed.  They promise unlimited, high tech sources of power.  But the externalities and security risks are equally unlimited. 

    Economists (and freedom lovers) prefer distributed sources of power (and wealth) over concentrated, centralized power; and for excellent reasons.  Efficiency, renewable sources like solar and biomass, and simple conservation can provide power, wealth, as well as security to all.  Let us heed Adam Smith, and the founding fathers.

    And clean local energy can be plenty high tech, too.
    Rate this comment: 12345

    MarkShapiro
    03/15/2007
    Posts:13
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    • Re: Best options first: efficiency, renewables
      "Economists (and freedom lovers) prefer distributed sources of power (and wealth) over concentrated, centralized power;"
      Does this refer to the pitting of the "haves" Vs. the "have nots"?
      Rate this comment: 12345

      Tagamet
      03/17/2007
      Posts:7
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      • Re: Best options first: efficiency, renewables
        Efficiency should be first. Distributed sources of power production and/or substitution should be key elements of the mix, especially of solar pricing/kwh finally falls significantly. Energy storage, both distributed and centralized is also a key element in a green system of systems.

        Fusion???  I would love it, but still seems way in the future.

        No nuclear (fission) system solves two major show stoppers.

        1. nuclear proliferation of weapons (either explosive or some type of dirty bomb).  Obviously true of old style lightwater reactors, but I bet  all types fail this test.

        2.  Long-term storage of wastes.  Especially so that they can NEVER be accessed at some time in the future (10,000 years) and be "weaponized." Can anyone guarantee that a future government in the center of the Eurasian continent (now known as "Russia") or North America (currently known as Bush's brain) could at some date in the future not be tempted to start creating weapon's.  Which supposes, of course, that in the most optimistic short-term one could succeed in disarming and creating a nuclear-weapon-free world. 
        Rate this comment: 12345

        Reptile
        03/21/2007
        Posts:11
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  • Clean Coal, An Oxymoron if there ever was one
    Reducing stack emissions is only part of the solution.  Don't forget about the mercury-poisoned streams, coal dust, destruction of mountains, polution of ground water sources, etc.

    Coal should be phased out, replaced by non-polluting, renewable resources.

    solarjohn.blogspot.com
    Rate this comment: 12345

    Solar John
    03/16/2007
    Posts:14
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    • Re: Clean Coal, An Oxymoron if there ever was one
      You may be right, in the end.  But cleaning up the stack emissions de minimus presumes that the other stuff, especially mercury, would be cleaned up too.

      The CO2 in my intuition is the stuff that would be really hard to get rid of because of volume.  But maybe I'm wrong.  Maybe using biological means, or catalysts, CO2 could broken down and then recombined in some form at leisure.

      Seems to me that carbon sequestration (also could apply to petroleum and natural gas combustion) could possibly be a significant element in a suite of low and high tech responses to the need to cut greenhouse gas emissions of all types.

      A big problem I see with coal is all those open pit mines.  And has anyone studied the contributions of methane gas emissions attendant to various types of coal mining opertions and THEIR contribution to global warming.  Especially now that it appears that the contribution of methane deriving from cattle farts--excessive concentration of corn in the diet of cattle (substituting for grass)--may actually be a significant contribution to greenhouse gases.  

      Also, off the subject, consider positive effects of niche markets for some technologies.  Thousand mile stretches of virtually uninhabited desert coasts (in Chile, for example, Australia, or perhaps the Arabian Peninsula) could be markets for small scale solar electrical plus desalination systems in very small communities, scientific outposts etc.

      Now they depend a lot on very inefficient generators and water trucked in, if that. In solar power/desalination systems a cistern can even be an energy storage device.

      Very high initial capital costs (unless one could mass produce standardized multifunction units) but relatively low operating costs.  To become common, however, such systems would need to be nearly maintenance free (A cousin--a mining engineer from Chile--just visited us in New York; that's why the energy needs of such environments is on my mind). Systems would need to function nearly unattended for maximum efficiency.  But maybe way too off the subject.

      A drop in the bucket to quench global warming?  Yes, but if combined with billions of others, an element of a fair start. 

      There are no silver bullets.
      Rate this comment: 12345

      Reptile
      03/21/2007
      Posts:11
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  • Hg & Fe
    in coal iron & mercury both r found, though insignificant quantity, both can cost health. Can't we think over this fact ? Hg can b used for production of some precious & useful elements which r rarely available on the earth.(Pl bear with my sms text.)
    Rate this comment: 12345

    vidya
    03/21/2007
    Posts:1
    • Re: Hg & Fe
      I know some big coal burning companies are looking into this.  Although the amounts of toxic compounds, like Hg, are small, due to the huge amounts of coal burned in some processes, and due to factors like reflux, these compounds are concentrated to amounts that become significant.  However, extracting them in economically vialbe processes still remains a technical difficulty, therefore one of the schools of thought is still to "make them inactive" (e.g.encapsulation in inert material) and dump them responsibly.  But I agree, finding a use for elements contained in toxic waste is far better than dumping toxic waste.  (This opens another debate - should one dump organic molecules, or oxidise them to CO2 and "dump" the CO2?  Which option will be the least harmful IN THE LONG RUN?)
      Rate this comment: 12345

      Daniel from ...
      01/09/2008
      Posts:8
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  • Wrong issue is addressed here
    If you start with a wrong premise you can't get the correct answer. First take the test to see if you are qualified to address the issue of coal:
    http://www.geocraft.com/WVFossils/GlobWarmTest/start.html

    If you pass the test then post.

    China's oil demand may rise 29 percent by 2010 from last year's levels, said an official from China National Petroleum Corp................
    Oil demand may reach 455 million metric tons (about 9.14 million barrels a day), ....... Imports may increase to 250 million tons....
    The only near term solution to their(& our)energy problem is coal and that is why China is building coal plants as rapidly as possible.

    http://home.comcast.net/~rlester06/Sowell.html
    Rate this comment: 12345

    crab
    03/23/2007
    Posts:1
    Avg Rating:
    5/5
    • Re: Wrong issue is addressed here
      I scored 70% on the test. That said, the most likely proposal for taxing carbon is to place a tax on the fuel at the well-head (oil) or the mine (coal). Wouldn't this discourage companies from investing in expensive carbon removal or sequestering?
      Rate this comment: 12345

      Phineas
      06/05/2009
      Posts:93
      Avg Rating:
      4/5

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