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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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  • 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 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.
  • 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.
  • 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.
  • 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.
  • 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.

  • by ChrisMaple ( 607946 ) on Monday January 22, 2007 @09:23PM (#17718270)
    Quite to the contrary, 10% is huge and very significant, particularly because none of it is imported. Great advantages in balance-of-trade and not funding terrorism.
  • 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.
  • Re:Iceland! (Score:3, Insightful)

    by DerekLyons ( 302214 ) <> on Monday January 22, 2007 @10:05PM (#17718622) 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.

    Do keep in mind that Iceland is geologically unique. It can run almost entirely off of geothermal because a) it's population is small, and b) geothermal sources are widely and readily available.
  • 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 ( e_engines/ [])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"...

  • 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.
  • by ranton ( 36917 ) on Monday January 22, 2007 @10:52PM (#17719002)
    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 oil, but it definetly isnt evening the playing field.

    The major problem with oil is that it truly is incredibly cheap. Incredibly cheap. It is why our world is so reliant on oil, because it is so much more economical than any alternatives. The problem is that the oil will eventually run out, and we are damaging our environment in the process. Subsidies would have nothing to do with making the competition fair. Subsidies are about making it unfair for the oil companies.

    And that is a good thing.
  • by dbIII ( 701233 ) on Monday January 22, 2007 @10:55PM (#17719014)
    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 a process - do you think it is likely that with the water used they end up in the ash dam and not in the air?

    Coal has enough real problems without making stuff up.

  • Re:Iceland (Score:5, Insightful)

    by MillionthMonkey ( 240664 ) on Monday January 22, 2007 @11:12PM (#17719126)
    Well, you'd think it would automatically be nice to live on top of lots of oil, but it isn't necessarily the case.
  • 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.
  • by Animats ( 122034 ) on Tuesday January 23, 2007 @01:04AM (#17719974) Homepage

    Read the actual study. [] 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.

  • by diablomonic ( 754193 ) on Tuesday January 23, 2007 @06:19AM (#17721292)
    Im so sick of people making statements like this. (not the posters here, the people writing the article.)

    I admit their intentions are good, but to be honest, I dont get it. lets be real. 10% by 2050? stop spending trillions on bogus wars over oil and useless no bid military contracts, divert it to wind, solar and electric car conversions and you would have ~ 500+ gigawatts of average energy right off the bat: do that each year for the time it takes to build the infrastructure involved (5-10 years) and BAM no more non-renewable energy. Am I crazy? Is this idea retarded? Why? because it involves not spending so much killing each other? FUCK YOU!

    why do we waste so much money killing each other and why is it considered sane to wage a trillion dollar war on a people who HAVE NOT attacked you but insane to consider diverting a large amount(and I mean most of it) to a purpose to the actual benefit of those who supplied it (taxpayers). Who the frack decided it was sane to spend billions on wars to protect oil but insane to spend the same amount WITHOUT killing or pissing anyone off to replace oil?

    OK, I should stop ranting now. Im just goddamn sick of it. War and the budgets involved are insane. Poxy plans to produce 10% of our power by the year 4001 are insane: they are a cop out. Put the date so far in the future it is irrelevant. HOw about this for a target: spend half as much on renewable energy as you do on killing other people and developing weapons to kill other people and pretty soon (10 yrs) you wont NEED to kill people as you wont need to steal their oil anymore.

  • by hey! ( 33014 ) on Tuesday January 23, 2007 @10:31AM (#17723146) Homepage Journal

    why do we waste so much money killing each other and why is it considered sane to wage a trillion dollar war on a people who HAVE NOT attacked you but insane to consider diverting a large amount(and I mean most of it) to a purpose to the actual benefit of those who supplied it (taxpayers).

    Because the old engineering dictum "good, fast, cheap, pick any two" applies to politics, with some interesting wrinkles.

    Most "good" options are either prohibitively expensive, or they pay off so far in the future nobody is all that itnerested in them. Anything in the US farther off than the next presidential election is the distant future.

    Cost is the most interesting political wrinkle of all. In politics, only discretionary costs count. When you are in a shooting war, nobody grudges money sent to "support the troops": it's not discretionary. So fighting a war is, from a political stance "free", until people start reckoning the cost in dead troops.

    Furthermore the definition of "good" in the context of war is particularly malleable. First off, let me say that I'm not one of the people who say the Iraq war is about oil. It is about oil, but I don't like to say it, because what people who do like to say it mean is usually wrong. A simple analogy will explain what I mean. The Iraq war is about oil in the same way sexual intercourse is about maximizing entropy: if you dig deep enough, you'll find that the statement is true in many profound and interesting ways. Despite the truth of the statement, it fails to capture the subjective experience.

    Now, getting back to "good": war is a chaotic, life or death situation. You have to accept the goals you can achieve. You may enter with a selfish calculus that looks like this: a democratic middle east is good for us because it will ensure a stable supply of oil (let's imagine we beleive this), so let's go in and spread democracy. However once you are in war, the balance tips from policy aims to victory. Like some lottery scratch ticket games, you have two ways to win: (1) achieve your policy aims or (2) win military victory. Either way you're a winner.

    Victory itself is subject to semantic engineering. Often you're lucky coming out of a war not much worse than when you went in. When things are really bad, all you have to do is argue you beat the worst possible case. The phrase "Peace with Honor" comes to mind.

    War looks like a "head I win, tails you lose" proposition if you're a president. You just have to avoid the mistakes all those other guys make of getting bogged down. You won't, because you're sure you're smarter than those other guys. If you didn't habitually think you were smarter than everybody else, you'd piss your pants at the prospect of being president.

    We probably could lick the problem of energy dependence in the mid to long term. My sense is that a diverse energy portfolio, like a diverse retirement portfolio, is the best option. You also like to have your investments liquid; the energy equivalent of that would be to have an efficient common means of energy distribution. A superconducting electric grid comes to mind. Naturally conservation is the quickest boost to energy self-sufficiency, but it is perceived as costly. Let's say we look at conservation as an "energy source", which makes sense in the context of a diversified energy portfolio. So, we start on diversification in year 1, including conservation, but not insisting conservation be fully "on line" right away. The distribution infrastructure is designed by year five and starts going in. At that time we start the push to bring on more energy source. By year fifteen, if we're not energy independent, even if we're not independent of any one energy source, let's say we're independent of the decisions of any one foreign country over our energy supplies. That's worthwhile and achievable.

    But, its costly and takes a long time. A quick war followed by falling energy prices as the world's energy producers tremble at the prospect of our military might gives us a kind of super-national energy sovereignty. Sound good, doesn't it?

  • by DG ( 989 ) on Tuesday January 23, 2007 @10:40AM (#17723252) Homepage Journal
    Before I start, keep in mind that I'm Canadian - so I'm immune to American partisan party politics. Democrat, Republican... all the same to me.

    And I'm a soldier too.

    Nobody would be happier than me if we could just scrap all the military apparatus in the world and spend all that money on things that would really benefit all of humanity - honest, no foolin'.

    But the sad state of the world today (although I think things are getting better) is that there exist people willing to exert deadly force on other people for personal gain - or to settle old scores - or just because they like it.

    Look at the Balkans, or Israel/Palestine, or the Sudan, or Rwanda, or Afghanistan... the list is extensive.

    Don't we, as a people, have a duty to protect the weak from would-be wolves? I say "yes".

    We're not very good at it yet. We're transitioning from a period where armies and warfare were legitimate means of conducting "intense diplomacy" between each other to a period where armies and warfare are used as instruments of stabilization and protection for people in states unable to provide either function for their own citizens. This is new stuff, and we're bound to get things wrong from time to time as we adopt to our new roles.

    But the end state is a world without genocide, without terrorism, without the impending threat of mass destruction and loss of life. A world where nobody has to worry about having their children hacked to death with machetes or blown to fragments by explosives.

    Is that not a worthy goal?

    Now I'll grant you that the USA's record on this of late is spottier than it should be. I honestly do not understand why Iraq was invaded; as all the reasons put forward by the current administration were clearly bullshit. And I agree with you that the American Iraqi Adventure has damaged, not improved, global security. (although now that you are there, you have to win!)

    But the power to correct that is in YOUR hands (you are an American citizen, right?) You have the ability to get yourself and your friends involved in the political process, to ensure that the people with the ability to deploy armies choose the good missions (like Afghanistan) over the unnecessary adventures (like Iraq).


I was playing poker the other night... with Tarot cards. I got a full house and 4 people died. -- Steven Wright