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MIT-Led Study Says Geothermal Energy Is Viable

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."

54 of 291 comments (clear)

  1. Iceland by 0racle · · Score: 5, Funny

    Iceland will be very happy to hear this.

    --
    "I use a Mac because I'm just better than you are."
    1. Re:Iceland by nwbvt · · Score: 4, Funny

      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...

      --
      Mathematics is made of 50 percent formulas, 50 percent proofs, and 50 percent imagination.
    2. Re:Iceland by MillionthMonkey · · Score: 4, Insightful

      Well, you'd think it would automatically be nice to live on top of lots of oil, but it isn't necessarily the case.

  2. Nukes are the answer! by dreddnott · · Score: 4, Interesting

    *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.

    --
    I may make you feel, but I can't make you think.
    1. Re:Nukes are the answer! by Chandon+Seldon · · Score: 2, 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!

      --
      -- The act of censorship is always worse than whatever is being censored. Always.
    2. Re:Nukes are the answer! by DilbertLand · · Score: 4, Funny

      Pass the aluminum foil please.....

    3. Re:Nukes are the answer! by dreddnott · · Score: 3, Funny

      Make up your mind! Are you an environmentalist or a neoconservative? I can't tell by the rhetoric.

      --
      I may make you feel, but I can't make you think.
    4. Re:Nukes are the answer! by 42Penguins · · Score: 2, Interesting

      I concur! And speaking of defending America through energy, may I suggest to you some terror-free gas? http://www.terrorfreeoil.org/

    5. Re:Nukes are the answer! by king-manic · · Score: 2, Interesting



      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 steam explosions when the operators purposely overode every failsafe for some reason. The major difference is a nuclear power plant is that after an accident, clean up takes longer. A modern reactor like a pebblebed or candu reactor would result in less nuclear waste and is even harder to have an accident occur.

      Nuclear isn't "optional" is is the next most abundant fuel after the hydrocarbons are gone. So it's either now or later. You don't have a choice not to use it.

      --
      "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
    6. Re:Nukes are the answer! by Paulrothrock · · Score: 4, Insightful

      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.

      --
      I'm in the hole of the broadband donut.
    7. Re:Nukes are the answer! by timmarhy · · Score: 2, Interesting

      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.

      --
      If you mod me down, I will become more powerful than you can imagine....
    8. Re:Nukes are the answer! by ranton · · Score: 2, Insightful

      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.
      --

      --
      -- All that is necessary for the triumph of evil is that good men do nothing. -- Edmund Burke
    9. Re:Nukes are the answer! by Paulrothrock · · Score: 2, 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 plant itself when it is end-of-lifed. Solar panel manufacturers should pay for the disposal or recycling of their panels at the end of life. Hell, McDonalds should pay for each pound of trash it generates with its packaging.

      In this way consumers would be able to make better decisions because the true costs of them would be visible in the price. It would remove the externalities that Adam Smith said were the problem with his economic theory. Also, by paying these fees to the government and passing along the price to the consumer, we would be able to eliminate almost all taxes that we currently pay.

      --
      I'm in the hole of the broadband donut.
  3. You heard it here first by Anonymous Coward · · Score: 4, Funny

    Don't come crying to me when we cool the planet core off and we end up in another ice age.

  4. Technology to use smaller temperature differences by wsherman · · Score: 4, Insightful

    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.

  5. Yes, yes we have a lot of resources by Dr.+Eggman · · Score: 4, Insightful

    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.

    --
    Demented But Determined.
    1. Re:Yes, yes we have a lot of resources by ThanatosMinor · · Score: 5, Funny

      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.

    2. Re:Yes, yes we have a lot of resources by Jarnin · · Score: 3, Funny

      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 we have, but it won't happen any day soon.
  6. Anti-nuclear bias by dsanfte · · Score: 4, Insightful

    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.

    --
    occultae nullus est respectus musicae - originally a Greek proverb
    1. Re:Anti-nuclear bias by TooMuchToDo · · Score: 4, Interesting
      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.

    2. Re:Anti-nuclear bias by TooMuchToDo · · Score: 4, Informative
      "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

    3. Re:Anti-nuclear bias by radtea · · Score: 4, Insightful

      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.

      --
      Blasphemy is a human right. Blasphemophobia kills.
    4. Re:Anti-nuclear bias by ductonius · · Score: 4, Insightful

      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.

    5. Re:Anti-nuclear bias by Voice+of+Meson · · 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.

      --
      Dammit! I had a good one.
  7. Actually, they are not . by WindBourne · · Score: 4, Insightful

    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.

    --
    I prefer the "u" in honour as it seems to be missing these days.
  8. Please don't mess with the ocean gradients by Overzeetop · · Score: 4, Interesting

    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)

    --
    Is it just my observation, or are there way too many stupid people in the world?
    1. Re:Please don't mess with the ocean gradients by maxume · · Score: 2, Interesting

      Puny human, ocean huge! Anyway, for starters:

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

      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.

      --
      Nerd rage is the funniest rage.
    2. Re:Please don't mess with the ocean gradients by InterGuru · · Score: 3, Informative

      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

      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.
  9. Iceland! by localman · · Score: 4, Interesting

    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... 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.

    1. Re:Iceland! by DerekLyons · · Score: 2, Insightful
      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.
    2. Re:Iceland! by jrumney · · Score: 2, Informative

      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.

  10. Re:Believe me ! I am NOT a Google SHILL !! by NoseBag · · Score: 4, Funny

    That's truly nice to know, Anonymous Coward.

    As I continue down the long pathway of life, meandering here and there, never knowing what might be around the next bend, I can take pleasure and comfort in knowing that - somewhere out there - there is an anomymous coward that is not a Google shill. Perhaps I shall pass this bit of arcania on to my children - and then to their children in turn - until at some point in the far distant future it becomes a family legend. Thank you, anonymous coward, thank you.

    --
    Cloned foods give the statement "We had that last week!" a whole new meaning.
  11. Re:GeoWhoWhat? by TranscendentalAnarch · · Score: 3, Informative

    It's not really saying much for it. Not long ago I had an excel spreadsheet listing all of the power generating stations in the entire state of California including their power generation capacity. Of the over 37,000 registered power stations (this includes quite a few extraneous ones) Diablo Canyon and San Onofre together provided about 40% of the total power used in the state. The majority of California's power generation is Nuclear, Oil/Gasoline, and Coal based.

  12. Unfortunately, there is opposition to this too by j.+andrew+rogers · · Score: 5, Insightful

    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.

    1. Re:Unfortunately, there is opposition to this too by ductonius · · Score: 2, Funny
      ... 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?
  13. Interview with Jeff Tester (MIT chairman) Sat. by sterlingda · · Score: 2, Interesting

    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 from 6:00 to 6:55 pm Eastern time. http://pesn.com/2007/01/22/9500449_MIT_Geothermal_ Report/

    --
    Tomorrow's news yesterday -- the bleeding, visionary edge.
  14. Re:How is this projected? by ChrisMaple · · Score: 3, Insightful

    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.

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  15. Iceland will be pissed. by r00t · · Score: 4, Funny

    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!

  16. Long Sterling engine by Nefarious+Wheel · · Score: 2, Insightful
    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/)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"...

    --
    Do not mock my vision of impractical footwear
  17. Re:GT being used here for years..it is good by WindBourne · · Score: 2, Interesting

    yeah, the GT homes really make sense. I grew up on wisc/ill border and saw -40 day and night (this was 60's and 70's). A number of the homes had heatpumps, but they were air based heat pumps. So instead, most have A.Cs (basically air based heat pumps), and gas heaters. But with the ground at a nice 55F, it has always made sense to use GT for both. On my next house, I think that it will be new and we will have them install a GT. May add an extra 5K, but worth it.

    --
    I prefer the "u" in honour as it seems to be missing these days.
  18. No quite accurate. by WindBourne · · Score: 4, Interesting

    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.

    --
    I prefer the "u" in honour as it seems to be missing these days.
  19. OH NO! by angst_ridden_hipster · · Score: 2, Funny

    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 :)

    --
    Eloi, Eloi, lema sabachtani?
    www.fogbound.net
  20. Unrepeated junk science for hire by dbIII · · Score: 2, Insightful
    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.

  21. Re:Global Cooling by quax · · Score: 4, Insightful

    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.

  22. The study is not that promising. by Animats · · Score: 3, Insightful

    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.

  23. Meet the Carnot cycle by Goonie · · Score: 3, Informative

    Nice try. Unfortunately, as I understand it, you can't beat the Carnot cycle no matter what technology you use.

    --

    Any sufficiently advanced technology is indistinguishable from a rigged demo
    --Andy Finkel (J. Klass?)
  24. Re:GeoWhoWhat? by ChicoLance · · Score: 4, Interesting
    (The following is all from memory. I worked at a geothermal plant long ago.)

    Yep, there are several plants in California. The twenty-odd plants that make up the Gysers north of Santa Rosa in the Bay Area, and I understand another field in the Imperial Valley. The Gysers field has been drying up over the years, despite them trying to pump water back down into it, and I haven't really checked the status of it in years.

    As much as this is an interesting technology, it's not perfect. The geothermal steam that goes through the plant is also loaded with sulfur and arsenic, which all has to be scrubbed out before the steam can be released through the air. The amount of solid sulfur removed per day was quite a bit.

    Another thing to keep in mind, that this Reuters article covering the same thing mentions that there are 61 projects in the works for 5000+ megawatts. For comparison, Diablo Canyon nuclear plant has two reactors, and each can produce over 1100+ megawatts. There is way more bang for the buck in other technologies, but they all have their drawbacks.

  25. Re:How is this projected? by diablomonic · · Score: 3, Insightful
    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.

    --
    watch "the money masters" on google video
  26. UK does not have a perfect safety record... by fantomas · · Score: 2, Interesting

    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=12626 82002

    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_fire

  27. Hope they won't produce earthquakes... by stiebing.ja · · Score: 2, Interesting

    ...like they did unfortunately in Basel (Switzerland) when they made tests to use geothermic energy on a new (?) way.
    They pumped water under high pressure into rocks several kilometers under the surface to further loosen the stones for later pumping of water through it. Obviously the rocks stood already under pressure which was released through the experiments and caused several earthquakes with a strength between 3.2 and 3.4 on the Richter scale - which is just strong enough to be noticed by humans.

    Don't believe it? See the report on tagesschau.de (sorry - german only) from 16.01.2007 and the site of the Swiss Deep Heat Mining Project which makes the experiments.

    --
    I lag
    1. Re:Hope they won't produce earthquakes... by rampant+poodle · · Score: 2, Informative

      Guess this is one of those lessons that has to be relearned every now and then. In the early 1960s a project to dispose of liquid wastes, (from Rocky Mountain Arsenal), by pumping them into deep drill holes caused a large number of earthquakes in the Denver, CO area. In 2004 a similar process was used to dispose of brine from a desalinization plant. A number of minor earthquakes quickly followed. Would guess that some Googling will reveal other incidents.

      General opinion is that the injected fluids lubricate surfaces along shear planes in the fault line. Wonder if this could actually be put to good use, (many minor earthquakes as opposed to the Big One), in areas prone to big, infrequent quakes.

  28. Re:How is this projected? by hey! · · Score: 2, Insightful

    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?

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  29. The Need for Global Security by DG · · Score: 3, Insightful

    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).

    DG

    --
    Want to learn about race cars? Read my Book
  30. not pollution free by peter303 · · Score: 3, Informative

    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.