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Coal — The Other Alt Fuel 135

Posted by Hemos from the kinda-like-pork-but-with-less-bacon dept.
This Wired piece is really a round-up about Coal: The Other Alt Fuel. One of the main stories is about an initiative to convert low-grade coal to other uses — like diesel fuel and so forth, but of course that nasty issue of carbon production comes up again.
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Coal — The Other Alt Fuel More

Coal — The Other Alt Fuel

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  • Write much? (Score:5, Funny)

    by Anonymous Coward on Monday November 13, 2006 @08:53AM (#16822110)
    These are Wired piece that is really a round-up about Coal: The Other Alt Fuel.

    English, motherfucker! Do you speak it?!

  • The issue is not the pollution (Score:3, Insightful)

    by BadAnalogyGuy ( 945258 ) <BadAnalogyGuy@gmail.com> on Monday November 13, 2006 @08:56AM (#16822126)
    The issue is whether we can sustain our usage at current levels indefinitely. The answer is of course, no. Can we then sustain current usage until a substitute energy source comes along? Possibly.

    In the meantime, coal will have to do, but we need to keep an eye on the clock because the longer we push off the transition to sustainable fuel sources, the sooner we'll hit the limits of our environment.
    • Well, er, it's also about the polution. At the end of the day, as long as you're burning a carbon based fuel, you're going to produce carbon dioxide. Sure it can be done 'cleaner' but you're still up against the twin problems
      • Limited availability, it may outlast me (I'm 53), it may outlast my children, but it won't go on forever. Tha't your point but it's only half the equation
      • Greenhouse Effect - as long as we go on producing the enormous amounts of carbon dioxide we will continute to contribute to climat

      • Re: (Score:3, Funny)

        by Amouth ( 879122 )
        well i guess that we need to get that whole robot thing going soon.. so that we can have them vent in unison towards the sun..

      • At the end of the day, as long as you're burning a carbon based fuel, you're going to produce carbon dioxide.

        You've overstated your case: the problem isn't all carbon-based fuels; the problem is only fossil-based fuels. There are two very significant alternatives -- ethanol and biodiesel -- that are carbon-based but do not result in a net increase in carbon dioxide, nor which have the "limited availability"* problem.

        *Yes, there are those who claim we don't have enough farmland, but that's because they're

    • Re: (Score:3, Interesting)

      by mgv ( 198488 ) *
      The issue is whether we can sustain our usage at current levels indefinitely. The answer is of course, no. Can we then sustain current usage until a substitute energy source comes along? Possibly.

      I've spent a bit of time reading around this area, and I think you can divide the problem into a couple of areas

      1. Depletion of reserves

      A big problem. Oil will run out, its really a question of when. If you believe the Peak Oil [wikipedia.org] proponents, we may well be in a depletion phase already. Certainly May 2005 was a peak

      • Re:The issue is not the pollution (Score:5, Interesting)

        by Shakrai ( 717556 ) on Monday November 13, 2006 @09:38AM (#16822498) Journal

        With oil reserves limited, attention is turning to other energy sources. Natural gas and Nuclear Power are the obvious choices.

        Unfortunately, natural gas isn't infinite, and while it will last a while, its loss will be accelerated by oil substitution. In other words, it will peak not long after whenever oil peaks.

        Nuclear power is contentious, difficult, and actually not in infinite supply. The world would consume all the nuclear power in a couple of decades; and there isn't any easy way to make its energy available for transportation.

        Have you ever heard of fuel reprocessing? Have you ever heard of breeder reactors that use U-238? How about using thorium? Estimates are that we have anywhere from 10,000 to 5,000,000,000 years worth of nuclear fuel remaining with these technologies that are largely already available. If by "contentious" you mean "NIMBY" then I suppose people will have to consider whether or not they'd rather accept a lower standard of living or nuclear power. I choose the latter.

        Geothermal, hydro and tidal power all have much promise, but many parts of the world have no access to any of these options.

        Some people think that hydro power winds up dumping almost as much greenhouse gas into the air (mainly methane) as a coal plant does. Why? Decaying vegetation in the reservoirs. In any case hydro and tidal are hardly eco-free options (and we've already used most of our hydro resources in the West) and geothermal spots eventually go cold.

        Energy is going to get more expensive. Transportable energy for cars, trucks and planes will be really difficult; and nobody is going to be flying around cheaply in 10 years time.

        I liked the idea of the hydrogen economy for transportable energy and nuclear fission/fusion for the backend (i.e: the grid). Whether or not hydrogen would scale (odds are it works for a SUV -- will it work for a 747?) is another matter and outside my area of expertise.

        In any case I don't see why nuclear isn't being seriously considered as an option. We know that renewables won't scale. We also know that nuclear technology works and properly used is safe.

        • Re: (Score:2, Interesting)

          by mgv ( 198488 ) *
          Have you ever heard of fuel reprocessing? Have you ever heard of breeder reactors that use U-238? How about using thorium? Estimates are that we have anywhere from 10,000 to 5,000,000,000 years worth of nuclear fuel remaining with these technologies that are largely already available. If by "contentious" you mean "NIMBY" then I suppose people will have to consider whether or not they'd rather accept a lower standard of living or nuclear power. I choose the latter.

          I have no great contention with what you are

          • Re: (Score:2)

            by Shakrai ( 717556 )

            Breeder reactors certainly overcome this limitation, but as I understand it are a much newer technology. I'm not saying they won't work, just that I'm not sure how well they will work in the long term.

            They aren't a new technology. Using them to create nuclear fuel to generate electricity would be a new use but breeder reactors have been around since the Manhattan Project. Where do you think the plutonium for nuclear weapons comes from?

            Bear in mind, nuclear won't fly planes or probably drive trucks. T

            • My only question is whether or not hydrogen scales well enough to power airplanes or ships.

              Yes.

              Planes: We can have them carry fewer passengers and we can make them out of lighter materials. As a last resort we can just fly slower - which would really save fuel. The problem is it would make it more expensive to fly - like it was 50 - 60 years ago.

              Ships: There are some plans for using giant kites to replace sails and reduce fuel consumption. Also, we used wind power long before we knew how to make t

              • Re: (Score:2)

                by Shakrai ( 717556 )

                Planes: We can have them carry fewer passengers and we can make them out of lighter materials. As a last resort we can just fly slower - which would really save fuel. The problem is it would make it more expensive to fly - like it was 50 - 60 years ago.

                Well that might not be a bad thing. One wonders if the current cost of air travel is at all realistic with the way the airlines are losing money left and right.

                Ships: There are some plans for using giant kites to replace sails and reduce fuel consumptio

        • I have serious problems with nuclear power, but I'd be interested in any real facts that might address my problems. It's been ten years since I investigated the issue, so maybe some advances have been made.

          I don't consider nuclear reactors terribly risky, my main problem comes from pollution. I'm also not particularly worried about a nuclear plant being in my backyard.

          The original push for nuclear power was mostly motivated by the defense industry. It provided a good smokescreen and a friendly motiv

          • Re: (Score:2)

            by Shakrai ( 717556 )

            The original push for nuclear power was mostly motivated by the defense industry.

            The original push for a lot of things came from the defense industry. That doesn't mean they are bad ideas or that we dismiss them. For better or worse it seems that our greatest achievements come out of the desire to kill the other guy before he kills us. Despite nuclear weapons can you honestly say that mankind is worse off for discovering how to split/fuse the atom?

            From what I understand, obtaining the fuel for nucle

            • The original push for a lot of things came from the defense industry. That doesn't mean they are bad ideas or that we dismiss them.

              Of course you are correct, and I apologize if I gave the impression this is what I was saying. Hell, I'm using the internet aren't I? As a researcher myself, I'm perfectly aware how much great research and development comes out of defense spending. It's an issue I do find lamentable, leaving physicists across their country scratching their heads and thinking "now how can I

          • Another issue : the waste issue is a fake boogeyman. Realistically, it's NOT that dangerous. One thing that the news media doesn't understand, even though this is only one step beyond common sense, is that long half life radioactive materials are not that dangerous. This is because the longer an isotope takes to decay, the less radiation it releases at any given time. (Doh!) So actually, we aren't screwing anyone over : even if we do end up burying waste in a mountain, in 100 years it won't be much more
        • How about using thorium?

          Sorry...there are MUCH more important uses [thottbot.com] for thorium and the cost of it is ridiculous. How else am I going to make my Runic gear [thottbot.com]

        • Some people think that hydro power winds up dumping almost as much greenhouse gas into the air (mainly methane) as a coal plant does. Why? Decaying vegetation in the reservoirs.

          The big difference is that those greenhouse gases are already in circulation while burning fossil fuels takes carbon that has been locked up for millions of years and adds it back into the carbon cycle.

          Decaying vegitation, burning trees, growing trees, none of these things actually change the amount of carbon in the environment, they

          • Re: (Score:2)

            by Shakrai ( 717556 )

            The big difference is that those greenhouse gases are already in circulation while burning fossil fuels takes carbon that has been locked up for millions of years and adds it back into the carbon cycle.

            Decaying vegitation, burning trees, growing trees, none of these things actually change the amount of carbon in the environment, they just move around the carbon that's already there.

            Which would be a decent point if I was making a hydro to coal comparison. But I was making a hydro to nuclear comparison

            • Which would be a decent point if I was making a hydro to coal comparison. But I was making a hydro to nuclear comparison.

              Sorry, my mistake

              And while your point about hydro being neutral CO2 is valid, forests do sequester carbon (slowly) over many years. Plants and animals die, some of them rot (carbon release), some of them get sequestered into sediment layers/peat bogs/etc (carbon removal). And what about the other environmental impacts of hydro schemes? What about the fact that most good sites in the West

        • Hydrogen is probably a red herring for portable energy. It costs too much (in terms of both dollars and energy) to produce, compress, and transport. Additionally, the most efficient method of producing hydrogen is using methane (natural gas), which releases C02 in the process. It'd be more economical to simply run cars straight off the methane.

          • Re: (Score:2)

            by Shakrai ( 717556 )

            It costs too much (in terms of both dollars and energy) to produce, compress, and transport.

            That's probably true today when the energy that you use to produce it comes from fossil fuels. Why not just burn them directly to power your car/ship/airplane? But if the energy used to produce hydrogen comes from low cost nuclear fission/renewable/nuclear fusion/insert_favorite_future_energy_source_here then it becomes much more economical. How else do you purpose to provide a portable (carbon neutral) source

            • I'm not shooting down nuclear -- I'm all for nuclear -- I was merely discussing hydrogen and the problems it faces in adoption. But even if we had a cheap, abundant source of electrical power, it would STILL be more efficient to put that power into batteries than use it to produce, compress, and distribute hydrogen, as each of those steps requires significant amounts of energy, and storing the stuff [wikipedia.org] isn't easy either. Electricity already has a fairly reliable and efficient distribution network (in most pl

      • Re: (Score:3, Informative)

        by 1u3hr ( 530656 )
        Nuclear power is contentious, difficult, and actually not in infinite supply. The world would consume all the nuclear power in a couple of decades; and there isn't any easy way to make its energy available for transportation.

        I'm not at all a nuke booster, but this isn't true. If you use breeder reactors you can convert non-fissile U238 to Plutonium, which multiplies your available fuel (U235) by a factor of hundreds. And it's not hard to transport electricity, it's just how efficient it is. Aside from cop

        • Re: (Score:3, Interesting)

          by mgv ( 198488 ) *
          I'm not at all a nuke booster, but this isn't true. If you use breeder reactors you can convert non-fissile U238 to Plutonium, which multiplies your available fuel (U235) by a factor of hundreds. And it's not hard to transport electricity, it's just how efficient it is. Aside from copper cables, there's the possibility of cracking water to make hydrogen. Further out, maybe superconducting cables. Also you can make portable reactors on barges and move them to where they're needed.

          I'm very sceptical about hyd

          • Re: (Score:2)

            by 1u3hr ( 530656 )
            If you really think electricity is easy to store, why are people getting so interested in fuel cells for laptops?

            I didn't say it was "easy to store". And laptops are a trivial use of electricity, convenience, weight are much more important than cost.

        • Re: (Score:2, Informative)

          by Mr. Slippery ( 47854 )

          If you use breeder reactors you can convert non-fissile U238 to Plutonium, which multiplies your available fuel (U235) by a factor of hundreds.

          The security implications of plutonium breeding make it unsuitable as a solution. And if you imagine fission scaling up to be the primary energy source, even with breeder reactors you still run out of uranium within decades [fraw.org.uk], perhaps a century. Reactor safety is a huge issue (no, pebble bed reators are not as safe as fission fans tell you [wikipedia.org]). And the waste problem

          • Re: (Score:2)

            by Shakrai ( 717556 )

            The security implications of plutonium breeding make it unsuitable as a solution

            Says who? If the United States doesn't do it then do you really think we can stop China or India from doing it? They aren't afraid of nuclear power. They seem to know that the fossil fuel gravy train is going to run out sooner or later. You could say the same thing about doing research with ebola, anthrax, smallpox or HIV, yet the last time I checked there were lots of civilian labs working with them.

            And if you imagine

          • Re: (Score:2)

            by 1u3hr ( 530656 )
            The security implications of plutonium breeding make it unsuitable as a solution.

            Yeah, unlike oil which has never caused any security problems or conflict.

            And if you imagine fission scaling up to be the primary energy source, even with breeder reactors you still run out of uranium within decades, perhaps a century.

            As I said, I'm not a booster, but the source you cite is obviously pushing an anti-nuclear agenda. I think it would last a century at least. By then there are a lot of alternatives that shoul

        • Re: (Score:2)

          by Reziac ( 43301 ) *
          The problems I see:

          The supply of uranium is not infinite.

          Uranium mining is a fairly "dirty" process that produces a lot of secondary contamination, since there tend to be a variety of toxic/radioactive components in the same stretch of rocks.

          There are already chunks of the SoCal desert, where uranium is found/mined, that are regarded as unfit for human use because of radioactivity. (That was why they put Edwards AFB out here in the first place -- it could do no harm to ground already unfit for habitation. Y
        • Further out, maybe superconducting cables.

          These are already being put to use in various areas. They are high temperature super conductors, just not room temperature super conductors. (High temperature as in above 10 kelvin). Here's an article on one instance.
          http://www.physorg.com/news77909735.html [physorg.com]

      • Bio Diesel (and/or ethanol) is a really promising alternative, but will require huge amounts of land to be converted to fuel production to support this - perhaps as much as 25% of the surface area of the US would be required to support the US at current rates of usage. In this sense it suffers the same problems as most renewables - environmental degredation.

        That assumes that you use "traditional" (modern) farming methods. Although many naysayers will step up and tell me that I'm crazy, every aspect of o

      • Geothermal, hydro and tidal power all have much promise, but many parts of the world have no access to any of these options.

        Over half the world's population lives near the coast, and for those who don't, we're working hard to bring the coast to them!

    • Re:The issue is not the pollution (Score:5, Interesting)

      by Shakrai ( 717556 ) on Monday November 13, 2006 @09:28AM (#16822408) Journal

      The issue is whether we can sustain our usage at current levels indefinitely. The answer is of course, no.

      Sure we can. It's called Nuclear Fission.

      What would you rather deal with? An energy source that dumps massive amounts of CO2 and radioactivity into the atmosphere or an energy source that is carbon neutral and produces nuclear waste that can be reprocessed into more fuel and/or stored somewhere (i.e: it's not released into the atmosphere)?

      There's no reason to accept a reduction in our standard of living and there's certainly no compelling reason to use coal over fission. We know that the waste can be reprocessed (the US just chooses not to), we know that the technology works and is safe. We also know that coal dumps massive amounts of CO2 into the atmosphere.

      • Barring serious economic recession (always a possibility), nuclear isn't really an option anymore. It takes awhile to get the plants online, and there would have to be a very large number of them built in a very short period of time. As an engineer, that'd be great news.

        Unfortunately, coal is about the only buffer fuel left that would take us over that hump that depleting oil supplies will leave. The hump gets worse every single day we wait ..

        People should have demanded Manhattan Project style investment in

        • Re: (Score:2)

          by Shakrai ( 717556 )

          Barring serious economic recession (always a possibility), nuclear isn't really an option anymore. It takes awhile to get the plants online, and there would have to be a very large number of them built in a very short period of time. As an engineer, that'd be great news.

          And it doesn't take awhile to build new coal power plants? Tell me, what's the better investment for the future?

          • Re: (Score:2)

            by xtal ( 49134 )

            And it doesn't take awhile to build new coal power plants? Tell me, what's the better investment for the future?

            A new coal boiler can be brought online quickly, as the regulatory requirements - security, environmental, and supply - are much lower. Adding onto an existing plant can be done even faster.

            As far as investments for the future go, funding fusion research en masse 20 years ago would seem like a pretty good deal, compared to the little skirmish we have in the middle east now. I'm worried about the m

            • Re: (Score:2)

              by Shakrai ( 717556 )

              A new coal boiler can be brought online quickly, as the regulatory requirements - security, environmental, and supply - are much lower. Adding onto an existing plant can be done even faster.

              And a new nuclear power plant can be built in four or five years. Do you really think our electrical grid is going to collapse in four or five years?

              As far as investments for the future go, funding fusion research en masse 20 years ago would seem like a pretty good deal, compared to the little skirmish we have in t

              • Re: (Score:2)

                by xtal ( 49134 )

                And a new nuclear power plant can be built in four or five years.

                Scaling up the uranium mines is the main problem in the scenario I am talking about. I would also question the ability to get nuclear approvals, even in a crisis, in 5 years. Coal, at least here, is already being expanded.

                Coal fields require little processing and are already capable of scaling in dramatic fashion. Uranium needs a lot of processing.

                I could care less if we burned coal 100% for 10 years, if at the end of the 10 years, we had Fusi

                • Re: (Score:2)

                  by Shakrai ( 717556 )

                  Scaling up the uranium mines is the main problem in the scenario I am talking about. I would also question the ability to get nuclear approvals, even in a crisis, in 5 years. Coal, at least here, is already being expanded.

                  The cost of the fuel (and the effort that goes into obtaining it) is a minor cost in the overall scheme of nuclear power. The approvals comes down to a NIMBY problem, to which I have no easy solution. I would also note though that coal power plants, transmission lines, cell towers, ai

        • Re: (Score:2)

          by dasunt ( 249686 )

          People should have demanded Manhattan Project style investment into nuclear fusion after the last energy crisis. We'll have another chance soon.

          Nuclear fusion also results in radioactive waste.

          Sure, often the products of nuclear fusion aren't radioactive (for the most part), but there structure tends to get a good dose of radioactivity.

          The true solution would be a population that is educated about nuclear power, radiation and risk.

          Maybe people will wise up if energy prices start to rise. There a

        • Re: (Score:2)

          by Jerf ( 17166 )
          Should the situation ever become that dire, there are still some options. Many of the costs associated with building a nuclear plant are basically phantoms, costs of excessive regulation, costs of defending against inevitable and well-funded litigation, and the cost of designing something that is often highly customized.

          You can't whack all those costs, but if push comes to shove many can be cut down by a lot. If we need a lot of plants, we'll standardize the design. The litigation costs can be basically el
      • I agree. If you count up all the people that have ever died as a result of radiation exposure, and all the people that have ever died as a result of pollution, nuclear is very, very, very safe.

        The only reason we don't have nuclear is because our government is in love with foreign oil. They ~talk~ about alternatives, but their action speaks volumes.

        For instance, no tariff on imported oil, but a 100% tariff on imported biodiesel. Then there is the IRS regulation section 179 that requires your vehicle be a
      • Unless you really want to use fission for vehicle propulsion [wikipedia.org].

        You could have battery-powered cars recharged from nuclear electric plants, but that wouldn't help much with air or sea transportation.

        • Re: (Score:2)

          by Shakrai ( 717556 )

          Unless you really want to use fission for vehicle propulsion.

          I mentioned this. The hydrogen economy may or may not provide the answer to mobile traffic. Obtaining hydrogen from sea water using fission as the power source. The other stumbling blocks (storage problems of hydrogen) are outside my area of expertise.

          In any case, bio-diesel or hydrogen can power cars. Ships can be powered by nuclear propulsion. Airplanes pose a problem, as I don't know if hydrogen/bio-diesel/etc would scale well (energy

    • Re: (Score:2)

      by thc69 ( 98798 )

      The issue is whether we can sustain our usage at current levels indefinitely.

      It would help if we'd stop burning it before we even mine it:
      http://en.wikipedia.org/wiki/Centralia%2C_Pennsylv ania [wikipedia.org]
      http://www.offroaders.com/album/centralia/centrali a.htm [offroaders.com]

      ;)

      Seriously, that's a cool place to explore. No, strike that, it's a _warm_ place to explore. Bring good boots...and fortitude.

  • Like a political season which never ends... (Score:3, Interesting)

    by rednip ( 186217 ) * on Monday November 13, 2006 @08:58AM (#16822148) Journal
    I don't know about the rest of you but my TV market is flooded with these 'clean coal advocacy' ads. Seems that four or five times a night some 6 year old start to lecture me about the promise of 'clean coal technology' in *her* lifetime. Or another which tells me that emissions are down 40% but generation is up double (or something like that; he didn't mention that the industry fought really hard against those same pollution controls).

    Seriously, is this how the energy companies are spending their windfall profits? Campaign style fantasies, and 'facts', I just can't wait for the negative advertising, like how wind farms slow down the earth's rotation.

    • And has been here for the last 20 years.

      A modern coal based power plant doesn't polute, unless you count CO2 as a polutant. Older coal based power plants were quite messy though.

      If you combine power generation with a community heating system, the energy use efficiency is also very high.

      • A modern coal based power plant doesn't polute, unless you count CO2 as a polutant.

        How many of these so-called modern coal-based power plants do we have in the US? Last I heard none of them were achieving 0 PPM soot output.

        Also, if you don't count CO2 as a pollutant, you must be insane. It's a known greenhouse gas and we know (for example) that we (humans) put out several times more CO2 than active volcanoes do every year. Since volcanism is often cited as a vehicle for climate change, I'd say that C

    • Re: (Score:2)

      by Svartalf ( 2997 )
      Most coal power plants are primary plants (meaning you're getting at least a fraction of the juice on the grid from them...), running 24x7 because it takes a while to spin one of those up. Those massive tall stacks? They're scrubbers as much as anything else. Yes, they dump pollutants, including CO2 into the air, but nothing like people make them out to. And, there's something else out there- several different processes patented in the late 1800's and early 1900's that cleanly convert coal into coke (cl
    • The commercials lately are because power companies have been trying to get licensed to build quite a few new plants accross the US and are getting blocked politically. The opposition is largely not based on the actual analysis of how much of various pollutants are contributed by coal compared to other generation methods or the relative costs, but merely on the false notion that even modern coal plants are horribly dirty. The power companies need these plants to be able to supply the amount of power that is
  • I recall reading years ago about generating electricity from coal using magnetohydrodynamics. Supposedly the efficiency was far higher than a carnot cycle (boil water / spin turbine) generator. What prevented MHD from ever reaching production?

  • As a North Dakotan (Score:4, Insightful)

    by alexwcovington ( 855979 ) on Monday November 13, 2006 @09:04AM (#16822200) Journal
    "Clean Coal" is a bunch of BS; the coal industry lobbies as much for relaxed pollution restrictions as they spend time implementing the air-quality mandates -- Even going to the point of flying in entire state legislatures for a meet-and-greet.

    I can appreciate the impact the coal industry can have on areas with depressed economies, but development must be done in an environmentally responsible manner; once the coal's gone, it's gone, but pollution damage can last a long time.
    • Most current coal plants are frankly dreadful in terms of efficiency and emissions. It's entirely possible to double their efficiency and reduce emissions by a similar margin. The costs of implementing such a system are another matter.
       
    • "Clean Coal" is a bunch of BS;

      That's actually what the coal industry lobbiest are saying.

      Clean coal burning power plants can be made. Gasification, scrubbers, hydrocarbon eating algees, these are technologies that exist. The problem is that they are expencive! And grand father clauses. The EPA ratchets down limits every year so that NEW coal burning plants must be cleaner. The problem is that it is so much more expensive to build a clean efficient plant than to repair and continue in the old plant, that mo
      • Yeah, the grandfather clause should have been for a maximum of 5 - 10 years, only enough to upgrade a plant or build a new one and no more.

        The problem is there are 60 lobbyist's for each politician, so it's hard for common sense or the voice of the people to be heard.

  • We need more CO2 anyway ... (Score:1, Funny)

    by Anonymous Coward
    ... since the experts say that the next cycle of glaciation is already overdue.

    We're at the end of the current 20,000-year interglacial, so it's back down to the brrrrr of another 80,000 years of ice in the 100,000-year cycle any time now.

    Pouring CO2 into the atmosphere may soon be our only way of keeping the US free of glaciers! ;-)

  • Hg, S, Fe, NOx & CO (Score:5, Informative)

    by grolaw ( 670747 ) on Monday November 13, 2006 @09:25AM (#16822374) Journal
    To name a few of the really, really serious biproducts of Coal usage. Hg precipitates out from exhaust at an alarming rate (*those states with coal-fired power plants all have massive Hg and CH2-Hg contamination: see, http://www.dnr.mo.gov/pubs/pub2100.pdf/ [mo.gov] and, http://www.moenviron.org/airqualitymercury.asp/ [moenviron.org] for one central US state's Hg warnings). Sulphur fom coal burning is the primary source of H2SO4 in acid rain that has decimated the lakes in the Northeast US and etched limestone (Cleopatra's Needle http://members.aol.com/Sokamoto31/ny.htm/ [aol.com] has been in NYC since 1881 and the two sides facing the prevailing wind have been etched free of inscription (perfect on all four sides when it was put it into place) due to acid rain) building materials. Nitrates (NOx) are the secondary sources of acid (HNO3 Nitric Acid being the most common) and a product of incomplete combustion of coal. About 75% of the coal-fired power plants scrub NOx out of the exhaust - but there appear to be no small-scale scrubbers consistent with vehicle use.

    Releasing more Carbon from the carbon sink is just one more addition to the ever-increasing load of greenhouse gasses on the planet.

    Iron - in its various forms will "poison" any catalytic converter small enough to fit on a vehicle.

    The cost of scrubbing or converting Coal into a cleaner-burning fuel is problematic and the energy used to scrub may well exceed the energy realized from the converted coal.

    • Re:Hg, S, Fe, NOx & CO (Score:3, Informative)

      by LWATCDR ( 28044 )
      Yes but.
      Coal is a hydrocarbon. It is possible to extract the hydrogen from it and use it as a fuel just as you can extract hydrogen from natural gas.
      You can convert it into coal gas and filter that to remove the sulfur and mercury.
      The big question is will it be practical?

      You have one really big technical error.
      "About 75% of the coal-fired power plants scrub NOx out of the exhaust - but there appear to be no small-scale scrubbers consistent with vehicle use."

      NOx doesn't come from from coal. If you burn any f
      • No technical error. NOx is a byproduct of Coal combustion and NOx isn't significant with simpler hydrocarbon fuels - remember, coal is a massive group of very long chain hydrocarbons such that it is a solid at room temp. The materials in "gasoline" are far shorther chain hydrocarbons and fairly uniform in composition. Control of combustion products is significantly easier to manage with simple fuels - as you point out.

        Extracting H2 frm Coal is an energy-intensive process that, at present, cannot be accomp
        • BTW yes there are vehicular scrubbers for NOx.
          They are called 3-way catalytic converters while not a scrubber they serve much the same function. Instead of capturing the NOx as some scrubbers do, they convert it back into N2 and O2.
          All modern cars have them. As I pointed out any liquid fuel made from coal that you would put in to a car would be chemically not very different than gasoline or diesel and would not have any more issues with NOx than we already have. That is one of the reasons that the US is m
      • >Coal is a hydrocarbon.

        Coal is mostly just carbon, 92-98% in the case of anthracite. There will be some hydrocarbons left over from its organic origins but they're a minority. Asphalt is an example of a solid hydrocarbon.

        >NOx is made when atmosphere nitrogen is held at too high a temperature for too long.

        Thank you for setting that straight, by the way. You don't even need fuel: lightning storms generate enough nitrates to be a noticeable source of fertilizer.

        • Re: (Score:2)

          by LWATCDR ( 28044 )
          "Coal is mostly just carbon, 92-98% in the case of anthracite"
          Is that by mass or by mole?

          Carbon is a lot more massive than Hydrogen. Even a very Hydrogen rich compound like methane, CH4 is 75% carbon by mass.
          Just asking because I know that coal gas is made of CH4, CO, and a small amount of Hydrogen.

  • Sasol [sasol.com] has been doing this for years [wikipedia.org].

    I don't see how this could be new

  • Fisher Tropsch (Score:4, Informative)

    by marcovje ( 205102 ) on Monday November 13, 2006 @09:41AM (#16822534)

    Isn't the Fisher-Trops 65 years old already? Germans used it in WWII for aux fuel, and so did South Africa during the boycott (SASOL).

    The Club of Rome also named this as possibility in 1980 (I never read the first report, only the revised one)
    • The main "problem" then and now is that it is simply more expensive. So it only gets interesting if the oil is gone (or hard to exploit).

      Of course it doesn't help for netto CO2 emissions. (or not much. It depends on conversion costs of both, but since C is further from C7Hx, I'd guess that converting coal is less efficient than crude oil)

      It's also possible to convert it into hydrogen (water-shift reaction followed by an additional step to convert the CO (+H2O) into more H2), but I don't know if this is re

    • Re: (Score:3, Informative)

      by drnlm ( 533500 )
      SASOL is still going strong here in South Africa. We have lots of coal, and it's quite expensive to import oil, so the whole process is still economically viable without the boycott. As a result, though, Sasolburg is one of the more polluted cities in the country (see amongst others the groundwork's 2002 annual report on this site [groundwork.org.za].)

  • Nothing new. (Score:1, Informative)

    by Anonymous Coward
    Sounds suspiciously like Fischer-Tropsch synthesis [wikipedia.org], which - I believe - has been used extensively for nearly a century. Anyway, I'd hardly call coal an "alternative" fuel. Coal fuels cooking fires, trains, and power plants. Coal is the primary source of Petrolium and Diesol in certain areas, and has been fuelling millions of cars for decades. By comparison, gasoline is an "alternative fuel".

  • green coal (Score:4, Insightful)

    by hamburger lady ( 218108 ) on Monday November 13, 2006 @09:58AM (#16822700)
    Venners acknowledges that the gasification process produces four times as much carbon dioxide as simply burning the coal.

    yeah, that's green all right.
  • If we're going to jump backward as far as coal, we may as well go all the way. I say, dinosaur-powered Flinstones appliances for all!
  • Before you decide to get warm fuzzy feelings about coal, go examine the issue of mountain top removal, and the consequences to the environment of the tailings that are left behind.

    • Re: (Score:2)

      by Reziac ( 43301 ) *
      Actually, most of the low-density coal (less efficient to burn, but far more economical to mine) is where it can be strip-mined, and the natural soil is poor or barren (or even entirely absent) to begin with. Ever been to the coal-producing areas of eastern Montana or NE Wyoming? Not much there but sagebrush and rocks. It's barely fit for grazing sheep; you certainly can't grow crops there.

      If you're careful about "archiving" whatever topsoil there was, strip-mined land can be returned to productivity, or ev

  • What a loathsome article (Score:3, Interesting)

    by Chris Pimlott ( 16212 ) on Monday November 13, 2006 @11:23AM (#16823678)
    The "clean coal" industry must be rather pleased with this article. It reads almost like a press release - It's clean! It's efficient! It uses coal we already have! It's good for our military! It's cheap! And what a name, "green fuel". How can it possibly be bad, "green" is in the name!

    It's not until the 16th paragraph when then happen to mention that, oh yeah, this "green fuel" process will release "massive amounts of carbon dioxide into the atmosphere" - four times as much. But don't worry, they'll be able to use a carbon-catching technology that doesn't even exist yet to make sure none of that CO2 actually escapes the factory. Right. There are dozens (if not hundreds) of coal plants operating in the US that aren't using the emissions reduction technology that's available now.

  • Just point out (Score:4, Informative)

    by Colin Smith ( 2679 ) on Monday November 13, 2006 @12:38PM (#16824666)
    That none of our power stations (including nuclear, fission and fusion) are going to get much above 40% efficient until we stop treating waste heat as waste. Overall efficiency can be doubled to the 80%-90% region by selling the heat for industrial processes, domestic water, space heating and to power chillers which can distribute cold water in hot regions.

    Most of our electricity is used to create or move heat from one place to another. It's highly ironic that power stations produce more energy as heat than they do as electricity. With District Heating and District Cooling it's possible to distribute heat and cold such that the requirement for space heating and air conditioning is massively reduced.

    This isn't going to happen any time soon, economically it simply isn't worth while, it's much cheaper to dig up coal or pipe oil or gas. That could change with the flick of a pen though. At the moment every working individual pays 30%-40% of their income as taxation, get rid of it and add the equivalent level of taxation to fuel sources, in particular the non green methods of generation. The utilities will then squeeze every Watt out of the fuel, and customers will make sure they don't waste any energy either. As a side effect, people will become much cheaper to employ.

     

    • Re: (Score:2, Interesting)

      by Anonymous Coward
      I remember seeing massive pipes in some cities in an East-European contry that were for distributing hot water to all the Socialist era housing blocks. It seemed odd to me until I understood that a hot water heater was a luxury (and probably still is for a large portion of the non-1st world countries).

      Every person in the housing block paid a percentage of the hot water bill (including amounts that leaked out) depending on the number of occupants in the individual apartment, since it was only metered at ea

    • Re: (Score:2)

      by khallow ( 566160 )

      That none of our power stations (including nuclear, fission and fusion) are going to get much above 40% efficient until we stop treating waste heat as waste. Overall efficiency can be doubled to the 80%-90% region by selling the heat for industrial processes, domestic water, space heating and to power chillers which can distribute cold water in hot regions.

      I don't believe that's correct. Power plants can achieve 40% because they vent heat to the environment. If that heat instead goes into industrial pro

      • I don't believe that's correct. Power plants can achieve 40% because they vent heat to the environment. If that heat instead goes into industrial processes, then there will be a reduction of the initial 40% efficiency. Overall efficiency will be better, but heat is generally a lower value product than electricity because it is even more difficult to transport and store.

        Instead of venting, it can be distributed through a heat distribution network. District heating is an old technology, insulated pipes can tr

    • Uh, the heat isn't treated as waste -- it drives the whole process. We're not talking about internal combustion -- nearly all power plants (except gas turbine) use the heat from [coal|oil|nuclear] fuel to create steam and drive turbines which turn the generators, and they're are designed to utilize every bit of heat that they can. Sure, some of it is exhausted, but as much of it is captured as possible. Some loss is unavoidable without superconductors, but we don't exactly have a cost effective method of

      • Sure, some of it is exhausted, but as much of it is captured as possible. Some loss is unavoidable without superconductors

        Actually the problem is the Carnot efficiency of the turbines, they're limited to about 40% efficient, the rest of the energy is exhausted as waste heat. District heating takes this waste heat, sells it to customers and increases the overall efficiency of the system to close to around 85%.

        Even if we could distribute energy as heat, it would still probably be safer to stick with electrict

    • Carnot efficiency is limited by the lowest and the highest temperatures in a power cycle. In my nuke plant our highest temperature is around 600 deg F, our lowest temperature is around 40 deg F (ocean water). This gives a maximum theoretical efficiency of 50%, and we actually run about 36% efficient or so. We've spent millions of dollars in the past few refueling outages to increase our effeciency a percent or two- a .1% increase in effiecency translates to over $600,000 a year in revenue. The only heat we

      • The discharge temperature of our steam turbines is around 100 deg F (into a vaccuum), and the water we use to cool that final stage is put back in the ocean at around 80 deg F.

        Um, yes... You know the whole idea is to replace the condenser with a heat distribution network... So instead of condensing the exhausted steam with seawater and thereby wasting the heat, you heat up a hot water distribution network and sell the heat. You lose a little efficiency from the steam turbine and gain a huge efficiency boos

        • It doesn't change the thermodynamics. It does change the type and location of the power generation. It's an economic tool which would substantially increase the overall efficiency of the power generators by making the inefficient ones uneconomic.

          There are numerous reasons why power plants are located in the places they are- some NIMBY, some regulatory, some thermodynamic, some supply chain.

          You would undo or override all those countless valid and important reasons in your quest for perfect efficiency? You're

          • You would undo or override all those countless valid and important reasons in your quest for perfect efficiency? You're like some statist tree hugging socialist freak who took one technology elective in college and now thinks he knows enough to use the frightful and destructive power of the government, overruling countless other rationale he dismisses as 'greedy' or 'selfish' without the slightest evaluation of them.

            Lol. In fact I'm a liberal, in the true sense of the word rather than the American one (you'

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