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Power United States Science

MIT-Led Study Says Geothermal Energy Is Viable 291

amigoro writes to tell us about a study for the US Department of Energy, led by MIT, indicating that geothermal energy could account for 10% of energy production in the US by 2050. The study concludes that geothermal is proven, could impose markedly lower environmental impacts than fossil-fuel and nuclear power plants, and is likely to be cost-competitive with the alternatives. This coverage in LiveScience points out how big a player geothermal already is in the US: "The United States is the world's biggest producer of geothermal energy. Nafi Toksöz, a geophysicist at MIT, noted that the electricity produced annually by geothermal plants now in use in California, Hawaii, Utah, and Nevada is comparable to that produced by solar and wind power combined."
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MIT-Led Study Says Geothermal Energy Is Viable

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  • Iceland (Score:5, Funny)

    by 0racle ( 667029 ) on Monday January 22, 2007 @08:37PM (#17717786)
    Iceland will be very happy to hear this.
    • Re:Iceland (Score:5, Funny)

      by nwbvt ( 768631 ) on Monday January 22, 2007 @08:53PM (#17717938)

      It must be nice to live right on top of the Mid-Atlantic Ridge and a volcanic hotspot and get tons of free energy.

      Well, except when one of the dozens of active volcanoes erupts, of course...

    • Iceland will be very happy to hear this.

      They already know. Iceland has been aggressively using geothermal energy for years. Unfortunately their techniques are not directly applicable except perhaps in Hawaii since they are essentially living on a volcano.

      10% of energy requirements is a huge amount for a country the size of the US with the energy consumption of the US. It means that China could easily achieve a similar figure.

      If you add that to wind you get a significant reduction in oil and gas import

      • no running costs, the consumables are minimal.

        While they don't have fuel costs, I understand that geothermal power currently has issues with maintenance costs. The steam has corrosive elements in it that results in increased mainentance required. Not saying that this outweighs the fuel costs of coal, but they are there. Just like even wind requires maintenance, and with solar you need to clean the solar panels occasionaly.

        significant reduction in oil and gas import requirements

        Oil used for electric power
    • by r00t ( 33219 ) on Monday January 22, 2007 @10:16PM (#17718722) Journal
      This is no different from an oil well drilled into some other country's oil. Iceland already claimed the Earth's core. The USA is basically stealing from Iceland. You may think the Earth's core is under the USA, but it's really under Iceland!
  • by dreddnott ( 555950 ) <dreddnott@yahoo.com> on Monday January 22, 2007 @08:37PM (#17717792) Homepage
    *Modern* nuclear power plants are the best solution to our coal and oil dependence.

    I like how the summary states that geothermal energy generation is cost-competitive with straw men like solar power, and lumps nuclear power plant environmental impact with the other straw man, fossil fuels.
    • Re: (Score:3, Funny)

      Ahh... I see you suggest modern nuclear power plants.

      Did you know that archaic nuclear power plants produce a whole bunch of "unusable" nuclear "waste"? Further, every time we put in a new nuclear power plant a terrorist gets a weapon of mass destruction!

      • by DilbertLand ( 863654 ) on Monday January 22, 2007 @08:45PM (#17717864)
        Pass the aluminum foil please.....
        • > Pass the aluminum foil please.....

          Dude, everyone knows that doesn't work - the metal acts as an antenna! If you want to BLOCK the signals, I suggest wearing a hat made of lead. As an added benefit, it's great exercise!
      • by dreddnott ( 555950 ) <dreddnott@yahoo.com> on Monday January 22, 2007 @08:46PM (#17717870) Homepage
        Make up your mind! Are you an environmentalist or a neoconservative? I can't tell by the rhetoric.
      • Ahh... I see you suggest modern nuclear power plants.

        Did you know that archaic nuclear power plants


        I appreciated that. Unofficial +1, Funny for you!

      • Re: (Score:3, Interesting)

        by 42Penguins ( 861511 )
        I concur! And speaking of defending America through energy, may I suggest to you some terror-free gas? http://www.terrorfreeoil.org/ [terrorfreeoil.org]
      • Re: (Score:3, Interesting)

        by king-manic ( 409855 )


        Ahh... I see you suggest modern nuclear power plants.

        Did you know that archaic nuclear power plants produce a whole bunch of "unusable" nuclear "waste"? Further, every time we put in a new nuclear power plant a terrorist gets a weapon of mass destruction!


        Although my sarcasm detector is deeply confused by your post, I'll hazard a reply anyways. A nuclear reactor can cause a large amount of damage but only slightly more then a standard gas/coal/oil power generation plant. Events like chernobyl were basically
        • You're right that nuclear power is a good idea. Absolutely.

          You're wrong that we should be using shit reactor designs like pebblebed or candu. Blech! Fast neutrons or you're wasting precious uranium.

      • every time we put in a new nuclear power plant a terrorist gets a weapon of mass destruction!

        The idea that terrorists could obtain nuclear weapons grade material and then actually use it to create a thermo-nuclear device is absurd. Its not like someone can just walk into the reactor building of a nuclear power plant and sneak some highly fissile plutonium into their pocket and walk out (for starters, they would be dead by the time they reached the door). If they could, why would they not instead steal it fr

        • So how exactly do you justify the statement: "every time we put in a new nuclear power plant a terrorist gets a weapon of mass destruction"?


          Anything is justified in the pursuit of humor, my good man.

          Can't you see that if we use nuclear power, the terrorists have already won? *WHOOSH*
        • "The idea that terrorists could obtain nuclear weapons grade material and then actually use it to create a thermo-nuclear device is absurd."

          I'll bite... Creating a "thermo-nuclear" device is not the only way to create a weapon of mass destruction. Dirty bombs are certainly a threat. Making x blocks of a critically important city center unlivable is certainly mass destruction. There is a fair amount of nuclear waste being stored on site at nuke plants. If the security guards at a nuke plant can grow lot
    • by WindBourne ( 631190 ) on Monday January 22, 2007 @08:49PM (#17717904) Journal
      Look, I am a proponent of Nukes. But we are in the nightmare that we are BECAUSE we became dependant on one main fuel source; Oil. Coal and natural gas is heavily used and that is also a big issue. OTH, if we use a combination of Nukes, Wind, Solar, Geothermal, wave, etc then if one has to be taken out of the mix, no big deal. More importantly, none can create a true monopoly (or oligolpoly) as is the current case with Oil.

      Not only do we need lots of GT, but western North America and many other places on this planet are perfect for it. One thing that America needs to do, is to better develop geothermal residential heating. That is to place the outside coil of a heat pump in the ground and use the relatively good temp for our house heat. Outside of states that are pumping natural gas, this is probably one of the better ways to lower energy useage in America.
    • Sell people permission to produce CO2, create a market for the trading of said permission. Require all energy producers to buy the requisite number of permits. Then put a limit on the amount of permits(CO2 production).

      Problem solved. That may include nuclear, it may not, but the energy producers will decide what solution is best for them.
       
    • by Paulrothrock ( 685079 ) on Monday January 22, 2007 @09:17PM (#17718210) Homepage Journal

      I'm not an anti-nuke freak. In fact, I think they're necessary for human expansion into space.

      However, I think that all sources of electricity should be treated equally. A per-megawatt subsidy to companies and individuals producing power should be implemented, and the electrical grid upgraded to allow the generation methods to compete fairly.

      This would allow individual regions to produce electricity in the most efficient ways. In some places nuclear might be the most cost effective, once the total cost of construction, disposal, and security are taken into account. In a lot of places, it won't be. The Midwest, with its small population, strong winds, and large amounts of land, would be perfectly suited to wind power. New York and Maryland would have tidal power. Arizona, Nevada, and New Mexico would use solar power.

      What we should not do is provide special loans and incentives for companies to choose nuclear power, or any other specific power generation technology. The government should step in to make the true costs of generation match the price as closely as possible, and then let the market determine what power generation method to use.

      • Re: (Score:2, Interesting)

        by timmarhy ( 659436 )
        your post makes no sense at all. first you say "A per-megawatt subsidy to companies and individuals producing power should be implemented" then in the next paragraph you say "What we should not do is provide special loans and incentives for companies to choose nuclear power". government should stay the fuck out of it.
      • Re: (Score:3, Insightful)

        by ranton ( 36917 )
        However, I think that all sources of electricity should be treated equally. A per-megawatt subsidy to companies and individuals producing power should be implemented, and the electrical grid upgraded to allow the generation methods to compete fairly.

        Uh, that makes no sense. Government subsidies are only needed if you need to give one or more types of power generation an artificial edge. That is the exact opposite of "competing fairly". It still might be the right thing to do if it stops our reliance on
        • Re: (Score:3, Interesting)

          I'm interested in making the economy work the way Adam Smith intended by removing externalities.

          There is an economic benefit in having a megawatt of electricity generated. So each power company should be given a subsidy for putting that megawatt into the grid.

          However, there's economic costs to every form of power generation. Coal, oil, and natural gas power plants should pay for each ton of CO2 and other pollutant they emit. Nuclear power plants should pay for the disposal of their fuel and the power pl

    • *Modern* nuclear power plants are the best solution to our coal and oil dependence.

      Good - let's give some people money to design them instead of the tweaked Westinghouse 1950's dinosaurs that the lobby money is pushing. Accelerated Thorium and others have potential but current production plants are holes to throw money into as well as other problems. Pebble bed advocates have some good points but should hold off on the wildest claims until constuction of the first large scale pilot plant is actually fini

  • by Anonymous Coward on Monday January 22, 2007 @08:38PM (#17717794)
    Don't come crying to me when we cool the planet core off and we end up in another ice age.
    • Wouldn't widespread use of geothermal energy mean that we would be effectively pumping heat directly from subterranean rock into the atmosphere? In other words, all this would achieve in the end would be to cut out the middle-man of the greenhouse effect and heat the atmosphere directly, rather than indirectly?

      Otherwise, sounds great...
  • by wsherman ( 154283 ) * on Monday January 22, 2007 @08:40PM (#17717820)

    In energy generation, the point of burning a fuel is usually just to create a temperature gradient. Using naturally occurring temperature gradients is certainly attractive.

    Existing energy generation technologies generally require a large difference between the high and low temperatures (e.g. steam generation). If economically feasible technologies are developed that can use gradients with smaller temperature differences then even the temperature gradients in the ocean would provide useful energy.

    • by Overzeetop ( 214511 ) on Monday January 22, 2007 @08:50PM (#17717916) Journal
      I'm fairly comfortable that we've got a long way to go to screw up the earths core temperature and/or magnetism (that's not based on any scientific knowledge, btw). It seems, however, that we could much more quickly screw up ocean currents by changing the thermal gradients that exist (again, not based on hard science numbers). Since much of our weather patterns are based on those ocean currents, I would venture that a real effort to convert to using ocean thermals to satify a larger portion of humaities need for energy could very well alter the global weather in just a few generations. Maybe the numbers don't support my gut feeling, but I would need to be convinved otherwise before I considered using ocean gradients for power.

      (and yes - using the gradients means reducing said gradients - it's that whole "laws of thermodynamics" thing Homer keeps reminding Lisa about)
      • Messing things up on a global scale would be difficult but messing up local gradients (right next the power plant) could definitely be a problem.

        With respect to ocean gradients on a global scale, the ocean gradients are fundamentally maintained by solar and geothermal heating (and cooling due to energy being radiated into space) so, in general, they would be replenished.

      • Re: (Score:2, Interesting)

        by maxume ( 22995 )
        Puny human, ocean huge! Anyway, for starters:

        http://www.noaa.gov/questions/question_082900.html [noaa.gov]

        Perhaps more interesting than anything else is that it states that a hurricane puts out about 1/2 the global electrical generation capacity; figure out how tiny a hurricane is compared to the ocean and you just have to be careful not to pull to much energy out in one particular place.
      • by InterGuru ( 50986 ) <(moc.urugretni) (ta) (dhj)> on Tuesday January 23, 2007 @05:22AM (#17721128)

        There is so much energy available that the whole world's energy consumption could be supplied with very minimal effect on the oceans. Quote below is from here [energybulletin.net]

        Indeed, the Earth has an enormous natural solar collector - the tropical oceans. "On an average day, 60 million square kilometers (23 million square miles) of tropical seas absorb an amount of solar radiation equal in heat content to about 250 billion barrels of oil." [1] Energy "equivalent to at least 4000 times the amount presently consumed by humans." [2] If we can tap into this renewable source, considering thermodynamics and entropy, approximately 1% of it could provide the entire current worldwide demand for energy. More than enough energy is available, we only need a way to get it - in a practical, cost-effective, ecologically safe and sustainable way.
    • by Goonie ( 8651 ) * <robert.merkel@b[ ... g ['ena' in gap]> on Tuesday January 23, 2007 @01:43AM (#17720206) Homepage
      Nice try. Unfortunately, as I understand it, you can't beat the Carnot cycle [wikipedia.org] no matter what technology you use.
  • by Dr. Eggman ( 932300 ) on Monday January 22, 2007 @08:41PM (#17717830)
    We get it. The US is a Big country with a lot of resources, you don't have to keep telling us stuff like "The United States is the world's biggest producer of geothermal energy." You know, even at only 20% of the nation's total electric energy consumption, the US is still the biggest commercial supplier of Nuclear energy? Beating out France and their 80% of their nation's energy consumption. We've got a lot of resources and a lot of needs, why do we have to favor Geothermal over Nuclear or Solar or Wind? Why can we invest heavily into all of them? Maybe with a diverse supply, we won't be caught with our pants down next time an energy resource starts to become more trouble than we need.
    • by ThanatosMinor ( 1046978 ) on Monday January 22, 2007 @08:46PM (#17717880)
      Because you know as soon as we start to depend on geothermal energy, we're going to have to deal with property disputes from mole men and lawsuits from members of SPECTRE whose secret subterranean headquarters are being leeched of their oh-so-important liquid hot magma.
    • by Qzukk ( 229616 )
      why do we have to favor Geothermal over Nuclear or Solar or Wind?

      Because only one can have the "best" return on investment, and that will be the one everyone invests in.
      • The best return on investment is the source with the plant/supply pipeline already built, followed closely by the source without any sort of expensive permits or regulations.
    • Re: (Score:3, Funny)

      by Jarnin ( 925269 )

      We've got a lot of resources and a lot of needs, why do we have to favor Geothermal over Nuclear or Solar or Wind? Why can we invest heavily into all of them?

      People like one solution for all their problems. 3000 years ago, folks had to pray to one god for good health and another god for plentiful harvests and good weather. Now-a-days most folks all pray to the same god for everything regardless of the situation, and they like it that way. They don't want to have to weigh benifits of going one route or another. They don't want to have to think about their options at all.

      Maybe one day we'll be able to get past the "one solution to all our problems" fixation w

    • by Warlok ( 89470 )

      Why can we invest heavily into all of them?

      There really is no reason. Go to the broker of your choice, open an account, and start buying stock in oil, natural gas, coal, wind, solar, and geothermal companies. Do some research to find out what other companies are doing B2B with the first set of companies to provide equipment and such, and invest in them as well. Now, talk to your friends and colleagues and get them to do the same. Wait a year or two, and viola! Diverse energy companies are now yours

  • Anti-nuclear bias (Score:5, Insightful)

    by dsanfte ( 443781 ) on Monday January 22, 2007 @08:47PM (#17717882) Journal
    When used correctly, nuclear power has no emissions and no leaked radioactivity. Its only associated problem is NIMBY-related, namely the long-term storage of "waste", which would in any case be less important if the US rescinded its silly ban on breeder reactors.
    • Re:Anti-nuclear bias (Score:5, Interesting)

      by TooMuchToDo ( 882796 ) on Monday January 22, 2007 @09:10PM (#17718122)
      Actually, I myself used to live in downtown chicago and recently moved out to a small town in rural Illinois. I live 20 miles away from a nuclear power plant in Byron, IL and on clear days can see the two condenser stacks from the second story of my home.

      I have no problem having a nuclear power plant in my "backyard", and would be more then happy if it was a fast breeder reactor that could continually burn it's fuel (as to have very little waste). If you want to get (cheap, less-polluting energy) you have to give (having production close by, being rational with regards to generation method).

      Most people don't get that a coal-fired electical generation facility puts out more radiation then a nuclear power plant. Go figure.

      • Most people don't get that a coal-fired electical generation facility puts out more radiation then a nuclear power plant.

        Where do you get this figure?

        • Re:Anti-nuclear bias (Score:5, Informative)

          by TooMuchToDo ( 882796 ) on Monday January 22, 2007 @09:24PM (#17718276)
          "Former ORNL researchers J. P. McBride, R. E. Moore, J. P. Witherspoon, and R. E. Blanco made this point in their article "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" in the December 8, 1978, issue of Science magazine. They concluded that Americans living near coal-fired power plants are exposed to higher radiation doses than those living near nuclear power plants that meet government regulations. This ironic situation remains true today and is addressed in this article."

          http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html [ornl.gov]

          • I invite people to actually read this article and consider things like the simplistic assumption made about pollution controls - a black box that lets out a certain percentage of everything. That may give you ideas about why there are no other papers like this despite it being published decades ago.

            For those who have not thought about the issue - consider that the primary purpose of pollution controls is actually to remove sulphur oxides and nitrous oxides. What do you think happens with solids with such

        • by dsanfte ( 443781 )
          Easiest match I could find. [ornl.gov]

          The link itself references the December 8th, 1978 Science magazine article "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants", where the authors determined that:

          "Americans living near coal-fired power plants are exposed to higher radiation doses than those living near nuclear power plants that meet government regulations. This ironic situation remains true today and is addressed in this article."

          More specifically:

          Trace quantities of uranium in coal range from l

    • by radtea ( 464814 ) on Monday January 22, 2007 @09:24PM (#17718280)
      When used correctly, nuclear power has no emissions and no leaked radioactivity.

      Sure, and when used "correctly" a coal plant doesn't emit anything much either. If we're comparing fantasies we can go on all day, each of us discounting anything we don't like about our preferred technology.

      The problem with conventional fission power is a) it is relatively easy to use incorrectly and b) when it is used incorrectly you have an expensive pile of radioactive scrap metal where you power plant used to be. The high energy density of the core means that small mistakes can produce large consequences, and the radiogenic properties of neutrons means that the whole core will be moderately radioactive, making in situ repair of the sort you can do on a coal plant impractical.

      Advanced pebble-bed designs fix some of this, particularly by taking most of the high-Z elements out of the core so you get much shorter lifetime low-level waste, but they are not yet a proven technology, thanks to the dearth of investment in the past thirty years.

      But honest proponents of nuclear power should own up to the problems rather than making exceptions for them. The earthmuffins are having the same effect on rational energy policy that Creationists used to have on evolutionary theory.

      Darwinian orthodoxy (particularly gradualism) went unchallenged for far longer than it should have because everyone was afraid that the kooks would seize on disagreements between evolutionists to justify their insane lies about the fundamental soundness of the theory. In the same way, admitting that there are real issues with fission power that have not yet been solved in any production environment (although there are some promising leads) may sound like you are "giving in" to the BANANAs (Build Absolutely Nothing Anywhere Near Anything) but in fact it is the first step to making the morons irrelevant to the debate.
      • by ductonius ( 705942 ) on Monday January 22, 2007 @10:36PM (#17718862) Homepage
        History contradicts you. The US, France, UK, Canada, Australia and Japan have been using nuclear power 'correctly' for as long as it's been around. It's relativly easy to use nuclear power responsibly. "Safety first" pretty much covers it.
        • Re: (Score:3, Informative)

          Um, I don't know about the others but I would not lump Australia in with those countries. Australia has one nuclear reactor which is primarily used for research and to produce radioactive materials for medical purposes.

          It does not AFAIK produce any power for general consumption. Even if it does produce some it is misleading to say Australia has been "using nuclear power". We're all coal and gas over here. ?Luckily? we have shiploads of the dirty stuff.
        • Throwing nuclear waste down a 65 metre hole in the ground including fissile material and then being surprised when the cap blows off and showers the area with radioactive waste does not appear to be a responsible use of nuclear power to me. Read up on Dounreay power station in Scotland: http://thescotsman.scotsman.com/index.cfm?id=1262 6 82002 [scotsman.com]

          Why did Windscale change its name to Sellafield? read up on the history of that plant. Hint: read up on the 1957 Windscale Fire: http://en.wikipedia.org/wiki/Windscale_ [wikipedia.org]
      • Wow. Since when are tons of Carbon Dioxide per kilowatt hour nothing?
    • by abigor ( 540274 )
      I believe Reagan lifted this ban in 1981 (assuming you are referring to the ban on reprocessing spent fuel), but uranium is so plentiful that there hasn't been much interest in reprocessing. In the interests of non-proliferation, the U.S. has voluntarily witheld from reprocessing and breeder reactors. Again, I am dredging this out of my memory, so I could be wrong here. But I'm pretty sure reprocessing and breeder reactors aren't in use more because of public opinion than anything else.
    • What nonsense. You are saying that it's impossible to make an informed and reasoned decision that nuclear power is not the best solution.

      The _fact_ is that there _are_ other alternatives, and the merits of all options, and their _total_ costs, should be considered when deciding which to pursue.

      Don't be so glib, and don't assume that everyone who thinks renewable energies are worth examining is a NIMBYer.

      As for this: "When used correctly..." as Einstein said:
      "Two things are infinite: the universe and human s
    • by dbIII ( 701233 )

      When used correctly, nuclear power has no emissions

      The magic bean lie again. Uranium comes out of the ground, the processing is a very energy intensive process with a surprising amount of chemical waste, and of course there is the waste fuel at intervals that have to be dealt with despite the dismissal of it above. Advocate nuclear on it's merits, but actually learn what is involved instead of beliving a very silly lie.

      As for breeders - I suggest you look at what happened with Superphoenix (not an accide

  • Iceland! (Score:5, Interesting)

    by localman ( 111171 ) on Monday January 22, 2007 @08:51PM (#17717926) Homepage
    I visited Iceland a couple years ago, and I became sold on geothermal. I mean, Iceland is a small country, but they have fairly high power needs per capita because of the cold climate, and they run almost entirely off geothermal, as I understand it. This isn't some apologetic green technology that is decades or more from delivering affordable massive power, like solar, wind, etc. No, this is the real thing: a geothermal plant puts out power at nuclear reactor levels. And these things are clean.

    My favorite part of the visit was swimming in the Blue Lagoon [art-iceland.com]... a spa built alongside the runoff from a geothermal power plant. Seriously: you're in the middle of a lava rock field, and boiling hot waste water pours from the power plant into a huge outdoor pool. In the cold air you can nearly cook yourself as you swim closer to the power plant. But it's clean enough to swim in.

    There are many criteria that need to be met to build a geothermal power station at a given location, but I think the research and development needed must be far less than for some other technologies, and the end result is completely proven, so the risks are minimal.

    My ideal-yet-realistic world features geothermal and nuclear supplementing each other, with the preference towards geothermal.

    Cheers.
    • Re: (Score:3, Insightful)

      by DerekLyons ( 302214 )

      I visited Iceland a couple years ago, and I became sold on geothermal. I mean, Iceland is a small country, but they have fairly high power needs per capita because of the cold climate, and they run almost entirely off geothermal, as I understand it. This isn't some apologetic green technology that is decades or more from delivering affordable massive power, like solar, wind, etc. No, this is the real thing: a geothermal plant puts out power at nuclear reactor levels. And these things are clean.

      Do keep in m

    • by phliar ( 87116 )

      Iceland sits on the Mid-Atlantic Ridge, i.e. on top of a volcano -- which means there's a lot of heat very close to the surface. In the middle of a continental mass -- say Colorado -- you have to go much deeper to get to usable heat and it may not be feasible.

      (But there is a giant volcano under Yellowstone. Hey, maybe that's Cheney's energy plan!)

    • you can nearly cook yourself as you swim closer to the power plant.

      I went there too, that was quite an experience. And the food was excellent-- I recommend the meat stew, it tastes almost like venison, but not quite...

    • Re: (Score:3, Informative)

      by jrumney ( 197329 )

      they run almost entirely off geothermal

      Iceland gets 82.7% of its electricity from Hydro dams. Most of the rest comes from Geothermal though. The Philippines on the other hand get about 27% of their electricity from Geothermal - they're the number two producer after the US.

  • If it wasn't for the ridiculous environmental regulations, we could supply a great deal of power from this location, probably only using 20 acres out of the entire site. However, it seems they would rather us continue burning fossil fuels than use renewable natural resources we already have.

    Has anyone ever calculated the heat capacity of the earth? I mean, if we start running geo-thermal plants I assume we are allowing the earth's core to cool quicker than it otherwise would have. Maybe the amount of cooli
    • by jo7hs2 ( 884069 )
      Yeah, but we could, like, pop the magma bubble and all die. OMG!!! Didn't U C t3h shows?
  • by j. andrew rogers ( 774820 ) on Monday January 22, 2007 @09:15PM (#17718164)
    Among the many reasons the high-quality geothermal resevoirs of the western US have not been exploited more than they have is that they attract opposition from environmental groups. Since the land is largerly Federal in many of the locales they are talking about, they use their clout in Washington DC to hinder local geothermal development since there is little overlap between their supporters in Congress and the constituencies that are affected, so it is a low-cost political bone. Instead they build space efficient natural gas and coal plants, which produce much more power with much less land use.

    Geothermal power plants of any scale cover large areas of land with a sparse network of pipes. It is usually not the case that you drill one well and put a turbine on top of it, instead you drill a large number of wells, about one well per 20-40 acres and aggregate the output at a central set of turbines. It is not as though you are paving the region, just putting in a small well-head and a pipe to transport/aggregate the output. Note that you also have to have pipes to pump the condensed water back into the ground in separate wells; they do not dump it into the atmosphere. Unfortunately this covers the land with a very sparse spiderweb of pipes that are deemed "ugly", offending the aesthetic sensibilities of the occasional jackrabbit or some such.

    The western US has enormous geothermal potential, but people will have to get used to the idea that there will be vast sections of high desert they never visit that will covered in pipe networks for heat transport. Perhaps they would like a coal plant built next door instead.
    • Re: (Score:2, Funny)

      by ductonius ( 705942 )
      ... sparse network of pipes... a large number of wells... aggregate the output at a central set of turbines.


      So, what you're saying is that the geothermal power station is a series of tubes?
    • No quite accurate. (Score:5, Interesting)

      by WindBourne ( 631190 ) on Monday January 22, 2007 @10:46PM (#17718944) Journal
      The problem is that most of the designs for geothermal is to use the prevailing heat as a wet well. That is they want to not only use the heat, but the local water. If they had a recycling GT set-up, then there would be a whole lot less impact and fight. But of course, that means spending some real money. A good example was the one in Wyoming next to YellowStone. Some far right wing group set up there and built one that used the water. Funny enough they simply discarded the water rather than re-inject (too much money). Needless to say, nearby springs and gysers lost their pressure. So a court injunction was obtained and they were stopped. Once a recycling GT can be built cheap, and effectively, you will see GT springing up all over here.
    • While many environmentalists would argue that a geothermal station does look "ugly", the more informed ones would take issue with the "spiderweb of pipes" (sic) due to the fact that they would significantly affect the movement patterns of many, many species inhabiting the desert. The jackrabbit or mouse or snake does not have it's "aesthetic sensibilities" offended, but more often than not, such developments hinder their daily movement. Many studies have shown that animals are reluctant to cross roads (ev
  • The article was succinct and straightforward, and ought to be read by every U.S. Congressman. The arguement on energy sources has been more or less front page since OPEC in the early 70s, but what has Congress done?

    Debate, debate, debate, but the U.S. Government Reps, Senators & Presidents have more or less refused to commit the country to policies designed to keep thye U.S. being held hostage to external threats on oil supply, UNTIL the price doubles in a short time. New policy implementation takes t
  • Um, if we were to convert the earth's thermal energy into electricity, wouldn't that lower the temperature? I imagine much of the electrical energy would convert back to heat, but a lot of it would be converted to mechanical energy. So perhaps this is a partial solution to global warming.

    Of course, I'm sure we'd hear some people complaining about the new problem of Global Cooling.
    • but a lot of it would be converted to mechanical energy
      Ends up as heat. Entropy.
       
    • Re: (Score:2, Interesting)

      Um, if we were to convert the earth's thermal energy into electricity, wouldn't that lower the temperature?

      Lower the temperature of the mantle, but raise the temperature of the biosphere. Instead of dumping gases into the atmosphere that increase the fraction of the sun's heat that sticks around we would instead directly inject heat energy into the atmosphere. You know those plants will probably only be 25% efficient when all is said and done. That means 75% of the heat energy taken out of the earth will contribute directly to global warming. Nice job.

      • Re:Global Cooling (Score:5, Insightful)

        by quax ( 19371 ) on Monday January 22, 2007 @11:44PM (#17719386)
        This is like arguing that the exhaust heat of car engines contribute to global warming rather than the exhaust gases. Direct heat dumping of mankind is negligible - even the hot wind passed in DC is more important. The latter will actually contain some green house gases. It's the gas stupid! CO2 and methane change the heat radiation equation of earth's atmosphere, that is the problem. GT just likes nuclear energy does not emit green house gases. That is why these are preferable power sources.

        I cringe at the fact that this was moderated interesting. The collective IQ of /. really is going down the drain.
         
        • Direct heat dumping of mankind is negligible
          I don't think so. Cities are always a couple degrees hotter than the surrounding countryside. Maybe it only seems negligible because no one has bothered to measure it. Large scale use of geothermal power would affect the temperature of the atmosphere, whether it is less or more than a given energy source depends on the relative efficiencies.
    • Most of the Earth's thermal energy originates in radioactive decay going on in the core. Essentially, the planet is a giant RTG. Local cooling can be caused by geothermal plants but we'd pretty much have to cover the planet with them to outrace heat production in the core.
  • by sterlingda ( 732011 ) on Monday January 22, 2007 @09:17PM (#17718202) Homepage Journal
    This coming Saturday, I will be conducting a 1-hour, live interviw with Jefferson Tester, who headed this Geothermal panel and report. It will be broadcast live [freeenergynow.net] from 6:00 to 6:55 pm Eastern time. http://pesn.com/2007/01/22/9500449_MIT_Geothermal_ Report/ [pesn.com]
  • I used to live in the Puna district on the Big Island, a couple miles away from the geothermal plant. It was really loud - I suppose that was the steam turbines causing all the noise. I always wondered what would happen if one of the pipes exploded. It would not be fun to breathe a giant cloud of hydrogen sulfide gas. Personally I'd feel much safer living near a nuclear plant, but that's just me. I believe nuclear's cheaper too, but maybe the good folks at MIT have figured out a way to bring the setup
    • So let me get this straight - you lived on an active volcanoe, but what you were worried about was the geothermal plants piping.

      Priorities need a little work there, mate.
  • Let me be the first to predict that stealing the earth's warmth will cause global cooling and an imminent ice age. Or else, releasing all the stored heat will contribute to global warming.

    Either way, the earth's core will probably stop spinning and we'll have to find a way to restart it.
  • by Nefarious Wheel ( 628136 ) on Monday January 22, 2007 @10:33PM (#17718844) Journal
    My old friend Long Sterling told me that you could exploit the energy differential between the ocean top and a ways beneath the surface by building a Sterling-cycle engine (http://en.wikipedia.org/wiki/Stirling_cycle#Marin e_engines/ [wikipedia.org])to take advantage of it.

    Perhaps with a series of tubes.

    OMG Sorry, just flashed to the future where some Alaskan senator tries to describe the grand oceanic heat pump network as "a series of routers"...

  • OH NO! (Score:3, Funny)

    by angst_ridden_hipster ( 23104 ) on Monday January 22, 2007 @10:46PM (#17718952) Homepage Journal
    Don't they know they'll end up cooling off the inside of the earth???

    Then what will we do?

    We'll have to have giant heat-exchanger space elevators circulating water/ice to cool the atmosphere back down, and we'll pump all our radioactive waste down deep to warm it back up in there.

    er.

    Nevermind :)
  • by Animats ( 122034 ) on Tuesday January 23, 2007 @01:04AM (#17719974) Homepage

    Read the actual study. [inel.gov] This doesn't look that promising.

    First, this isn't a renewable resource. Over time, the rock cools, and more wells have to be drilled. "If there is no temperature decline, then the heat is not being efficiently removed from the rock. If there is too much temperature decline, either the reservoir must be replaced by drilling and fracturing new rock volume, or the efficiency of the surface equipment will be reduced and project economics will suffer."

    Second, outside of the few locations where you can get steam at 200-300C from shallow holes, the thermal performance of these systems is unimpressive. Efficiency = (Tin - Tout) / Tout, with temperatures measured from absolute zero, remember. So you need big low-pressure steam systems to extract the power. It's 1890s steam technology, low temperature and low pressure. The study assumes that the systems for recovering energy from low-grade steam will improve in efficiency, but heat exchangers and steam turbines have been developed for well over a century, and are mature technologies.

    Worse, most of the good locations are in the empty parts of the United States. Idaho, Wyoming, Colorado, inland Oregon, and northern Utah have the best heat reservoirs. East of the Mississippi, zilch. (See fig. 1.4) Electricity would have to be transmitted thousands of miles to be useful, and there's no local use for the waste heat. Hawaii looks promising, but that's because it has cities near volcanoes.

    Several experimental plants have been built since 1980, and none of them could even pay their own operating costs, let alone recover their capital cost. (Too many DoE "demonstration projects" are like that.) The study actually doesn't recommend building power plants. It recommends ... another study.

  • not pollution free (Score:4, Informative)

    by peter303 ( 12292 ) on Tuesday January 23, 2007 @11:22AM (#17723760)
    I worked for a company once that had geothermal as a side business and am aware of its short comings:
    (1) The ground reservoir require constant "care and attention". Drill holes block up from mineralized water gunk much like some parts of the country see inthere house water pipes. Circulation pressure is fickle. It cant drop if there are new cracks in the rocks. You have to pump or re-drill.
    (2) There are waste products- generally highly mineralized water that no one else can use. Hawaii is avoided geothermal development for this reason.
    (3) A "dry" field may require a consistent water source. The US West is short on water supplies.
    (4) You can set off earthquakes when you pump fluids. Rocky Mountain flats is the classic example, but this has happened to a lessor degree in the Salton Sea, CA and Geysers, CA area, both in seismic areas.

    Still the benefits may outweigh the drawbacks. No carbon pollution.
    Oil field and coal methane development have similar drawbacks too.

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