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Alaska Looks To Volcanos For Geothermal Energy

Posted by kdawson on Mon Jul 28, 2008 11:05 PM
from the don't-stamp-so-hard dept.
Iddo Genuth writes "Alaskan state officials have recently announced their intention to begin funding the exploration and surveying of Alaska's largest volcanoes in hopes of utilizing these as a source of geothermal energy. They say this volcano could provide enough energy to power thousands of households, and according to some estimates, Alaska's volcanoes and hot springs could supply up to 25% of the state's energy needs."
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  • While very neat, if we did tap geothermal resources nationwide to get up to supplying 25% of our electrical needs within a few decades, we'd still be behind Iceland. According to Wikipedia [wikipedia.org], Iceland generates 26.5 of its electricity from geothermal power. Strange to think that a place called Iceland has so much available heat for power generation.

    Going a bit astray, has anyone seen the episode of Science Channel's "Eco-Tech" featuring the rooftop windmills [youtube.com] designed by Aerotecture [aerotecture.com]? Pretty cool.
    • by LaskoVortex (1153471) on Monday July 28 2008, @11:17PM (#24380369)

      if we did tap geothermal resources nationwide to get up to supplying 25% of our electrical needs within a few decades

      I'm of the opinion that the human race will eventually get close to 90% of its energy needs from geothermal sources. Wind and solar probably can't deliver the wattage. What people don't realize and what they don't want to believe, is that the world is not filled up with oil in the middle. Instead, its filled with molten rock, and beyond that, molten metals. And there is a lot of it in there. All you need to do is invest in shunting sea water a few miles into the earth and harvesting the energy as it boils out. Other than the initial investment, it wouldn't take coal or oil--both of which WILL run out.

      • by TapeCutter (624760) * on Tuesday July 29 2008, @12:07AM (#24380723) Journal
        The CSIRO in Australia has been investigating the practicality of producing electricity from granite deposits [ga.gov.au] since the early nineties. Also since the nineties the same organisation has been saying that Australia could produce all it's power and then some from either solar or wind.

        The problem for the last 11yrs in this country has been purely political as we stood stubbornly by the US. Because of this misdirected loyalty our power generation remains 90+% derived from coal and we have seen many innovations payed for by taxpayers sold off to private companies in the EU and elsewhere.

        Now that our breadbasket (the Murry-Darling basin) is regularly producing half of what it did just a couple of decades ago people are starting to pay attention.
        • by LWATCDR (28044) on Tuesday July 29 2008, @11:16AM (#24387065) Homepage Journal

          "The problem for the last 11yrs in this country has been purely political as we stood stubbornly by the US. Because of this misdirected loyalty our power generation remains 90+% derived from coal and we have seen many innovations payed for by taxpayers sold off to private companies in the EU and elsewhere. "
          Wow and just how is the US to blame for this?
          The US told you to not build solar, or wind? Or even nuclear reactors?
          Or did you keep to coal because it was cheap and you have a crap load of it. Not to mention that Australia makes a bunch of money selling it to China?
          Please take some responsibility for your own actions. Lots of other countries are allies of the US like Germany and Japan and they both have invested heavily in to none carbon based power systems.
          Just silly this whole "Devil made me do it" mentality take some responsibility.

      • Re: (Score:3, Insightful)

        In some places we are lucky enough that there is water already in cracks in the hot rock. Now while geothermal electricity generation of a sort has been used since the 1890s there are the two problems of drilling very deep holes and the amout of capital required to build any sort of large thermal plant. It's hard to convince people to pay for something that won't pay for itself for a decade even if it is going to last a century - even worse when it's going to take more than five years to build.

        I can't res

      • by jd (1658) <imipak.yahoo@com> on Tuesday July 29 2008, @12:58AM (#24381079) Homepage Journal

        Geothermal power is nice, but does have its limits. There are reports suggesting that heavy use of geothermal power can increase the frequency of mini earth tremors, which is probably not good. Also, you are not generally tapping the earth's core (which has plenty of heat) but some local magma reservoir (which has rather less) or a channel through which magma flows (which is not much of a reservoir at all, and could in principle be blocked, which may explain said earlier reports).

        In the long term, fusion power is the best solution, but the technology necessary to achieve fusion is taking a painfully long time. I still favour rounding up the fusion scientists, locking them in a building in Alaska with as much money as they can possibly need, and slowly turning down the heat until they quit with the politicking and bitching about whose method is "better" and get something that works.

        In the short term, fusion isn't going to happen nearly fast enough to handle the present or any future oil crisis. Geothermal power can. As others have mentioned, other countries use it extensively, such as Iceland and New Zealand. Alaska could probably benefit from it, and the Pacific Northwest is riddled with volcanoes and magma reservoirs. The Pacific Northwest is also a major energy user, making it an ideal place to have major generators.

      • by BlackPignouf (1017012) on Tuesday July 29 2008, @02:45AM (#24381629)

        "solar probably can't deliver the wattage".

        Yeah, right, it's not like the sun would deliver 168 PW to the Earth at any given time, while mankind "only" uses 500EJ a year.
        500EJ/168 PW ~= 50 minutes worth of solar radiation would be enough to power whole mankind for a year.

        Geothermal sources can really be interesting, but you need to find good ones, and still dig a few kilometers if you want to get high-quality heat and produce electricity. You don't need to dig an inch to collect solar radiation.

        • by LaskoVortex (1153471) on Monday July 28 2008, @11:40PM (#24380565)

          The key is that when we run low on heat from the Earth's core in the distant future

          When the earth's core (the molten metal part that causes the magnetic field that deflects the solar ion radiation) finally goes solid from our geothermal harvesting, we will have mutated to a form we probably couldn't recognize as being evolved from ourselves--and we certainly wouldn't give a damn about the little alien looking marmots either.

        • by davester666 (731373) on Monday July 28 2008, @11:57PM (#24380657) Journal

          Yeah, once core starts to cool, we can just nuke it to warm it back up. Finally, a good use for our nuclear arsenal!

          And to access these geothermal reserves, they would still have to drill down to gain access to them, and if they just "happen" to hit oil, so much the better.

          • by pimpimpim (811140) on Tuesday July 29 2008, @04:49AM (#24382235)
            Hmm, but for a drill like that, you'd need a drill made out of Unobtanium. With the current funding it will take years to develop! And the crew has to consist of at least a woman, a scientist, an astronaut, and a guy who dies.
        • by Dahamma (304068) on Monday July 28 2008, @11:58PM (#24380667)

          Oh come on, someone modded this *informative*?

          Calling geothermal energy a "temporary fix" is about as useful as calling solar energy a temporary fix. Really, I don't think it's too shortsighted to consider an energy source that could provide power for millions (geothermal) vs billions (solar) of years as more than "temporary". Especially considering how we will have used up the relatively scarce (geologically speaking) oil resource we are looking to replace in the scale of hundreds of years. Hell, I'd be happy to see people think 50 years in advance, imagine what we could do with nuclear power if we'd invest for results with a payoff that far away...

          • by BazilBBrush (1259370) on Tuesday July 29 2008, @12:24AM (#24380863)

            I was going to mod him down but there wasn't a suitable category - say like 'Missing The Facts'.

            First off, like how much heat energy is actually present beneath the mantle? A. Big number.
            Secondly, how long it will take for the magma / iron + whatever core to cool to a point where the magnetic field decreases enough? A. Another big number.

            It scares me that people with so little perception of physical reality make comments as if they understand.

            Just a point for you too re nuclear power. It may outlast us but Uranium reserves are not infinite either.
            Now if we could only get Fusion happening...

            All in all geothermal is a great idea - as mentioned in Iceland, and I think the Kiwis (New Zealand) harvest a bit for sparks and even the UK for hot water if I am not mistaken.

            No not available everywhere but whatever helps...
            • Re: (Score:3, Interesting)

              Does retrieving geothermal energy make it harder to retrieve more energy from it in the future? If so, is there enough of it readily achievable so that it wouldn't matter anyway?
              • by ThePeices (635180) on Tuesday July 29 2008, @01:27AM (#24381247)

                yes, it is definitely possible to 'deplete' a geothermal resource, but it will recover given enough time ( lots of time ). For example the Wairakei geothermal field here in New Zealand has depleted somewhat because they oversized the geothermal plant when it was built and it has been running for 60 years! ( but we forgive them, it was built in 1958, and it is the second oldest geothermal power plant in the world ). The wikipedia article on geothermal power describes depletion in more detail

                http://en.wikipedia.org/wiki/Geothermal_power [wikipedia.org]

            • by Ex-MislTech (557759) on Tuesday July 29 2008, @05:30AM (#24382421)

              First and foremost I am against nuclear power, but...

              To be fair to it, uranium is not the only fuel.

              Thorium breeder reactors will work as well.

              Thorium is much more common, about as common as lead.

              And in a breeder setup it "makes" uranium.

              http://en.wikipedia.org/wiki/Thorium#Thorium_as_a_nuclear_fuel [wikipedia.org]

              That being said, man's history with reactor safety is poor.

              Wind, Solar, Geothermal, Tidal, Bio fuels, and Ocean Current
              Capture is more than enough power by far.

              The Antarctic current alone is 135 times the flow of all
              the rivers on Earth Combined and the Aquanator style device
              works well at capturing it.

              http://en.wikipedia.org/wiki/Antarctic_Circumpolar_Current [wikipedia.org]

              Needless to say there are many other underwater currents
              with a great deal of power, and some can be harnessed
              to some degree without a negative impact.

              So let's play SeaLab and make a modern Atlantis and end
              this oil mess before it turns the oceans in a hydrogen
              sulfide soup.

              http://www.sciencedaily.com/releases/2003/11/031104063957.htm [sciencedaily.com]

              So in a range of choices, anything but oil.

              The oceans are a giant CO2 sink, so as much as we measure
              in the air it is worse in the oceans.

        • by EdIII (1114411) * on Tuesday July 29 2008, @01:08AM (#24381141)

          That's cute. Ummm, what on Earth (no pun intended) are you talking about and how did you get modded informative?

          We will probably never get *any* energy from the Earth's core at all. The crust of the Earth alone is 3-5 miles thick under the oceans and 15-35 miles thick on the continents.

          Now, the Earth's core is thought to have at least half to ninety percent of it's energy generated from nuclear decay. That means we CANT draw all that energy off at once, even if we could draw it all in the first place. We would be rationed. There is also tidal forces to consider as well. The orbit around the Sun and the Moon for example can generate large amounts of energy in the Earth's core too.

          Drilling even 20,000 feet is an ACCOMPLISHMENT. To my knowledge, and I have been on drilling rigs and know people in drilling companies, we have never broken 50,000 feet commercially. So ANYTHING we do is going to be in the CRUST, and not the mantle and certainly not the core. To get to the mantle of the earth on a continent we would have to drill in excess of 75,000 feet. I am pretty sure that at that depth concrete won't do it to create a stable pipeline and you will need some pretty neat material to withstand those stresses and keep a hole open.

          Furthermore, the Sun provides an incredible amount of energy. Off the top of my head I think it is near 400 watts per square meter or approximately 1.8*10^17 WATTS total at any given time. That's a lot. 90%+ of the energy present in the crust of the Earth comes from the Sun. The core is providing a negligible amount of that power and most is probably received through direct volcanic activity and not emissions. Don't quote me on that, it's just a guess.

          Considering that, in 2005 we required nearly 500 quadrillion BTUs of energy for the whole planet. Nearly 700 quadrillion is projected to be required in 2030. So let's just top that off at a nice quintillion BTUs. After multiplying that by .293 to convert to WATTS we get 293 quadrillion WATTS of energy. That is also PER YEAR. How much of that can be provided by the energy received from the Sun in the crust? 100%.

          So basically the Sun can give us all the energy we will need for one year in one day and probably be done before breakfast is over.

          We would have to use ALL the energy from the crust of the Earth FASTER than the SUN can replenish it BEFORE we could even begin to siphon off energy from the core.

          So yes, you are correct that the energy at the Earth's core is not unlimited, nor is energy unlimited in the Sun or from any orbit. However, for a VERY LONG TIME we would only be able to suck a small droplet of blood of what is sure to be a gargantuan beast of energy. To say we could ever consume enough energy to surpass the energy provided by the Sun at any one moment is just fantastic, awesome, and up there with the Tooth Fairy.

          You may also want to consider that the 293 quadrillion BTU requirement represents an INCREDIBLE amount of waste and inefficiency with our processes. I bet that by the time we get to 2075 (if we are not dead already) it will be because we figured out how to survive on far less than that.

            • by EdIII (1114411) * on Tuesday July 29 2008, @01:53AM (#24381353)

              I mentioned NOTHING about solar power at all. I am simply talking about the amount of energy that the Earth is exposed to at any one moment REGARDLESS OF EFFICIENCIES OR METHODS/PROCESSES OF HARNESSING SAID ENERGY.

              That energy has to go SOMEWHERE. The air, the oceans, or the crust. Try reading my post before making derisive comments.

              "So basically the Sun can give us all the energy we will need for one year in one day and probably be done before breakfast is over."

              If we were taking the incredible amounts of energy from the crust that the poster suggested, I simply pointed out that the Sun would put that much energy back in a very small fraction of the time it took to "pump" it out of the crust.

              I never mentioned any specific technologies that were applied to convert the heat energy of the crust to electricity, nor did I mention anything about solar technologies being a suitable replacement for geothermal.

              I ONLY POINTED OUT THAT WE COULD NEVER USE ALL THE ENERGY IN THE CORE DUE TO 1) WE CANT REACH IT AND 2) WE COULD NOT USE IT ALL QUICK ENOUGH.

              P.S - Try reading some news on occasion. Solar cell efficiency surpassed 15% a LONG FARKING TIME AGO. It is not in production, but we have achieved it. I am open to using any technology, but I am honestly fed up with all the poor references that people use when it comes to environmental technologies. It's not a contest, and I don't give a crap WHICH technology we use. Just as long as we start using something renewable that does not kill us all in 50 years.

            • by jacquesm (154384) <.j. .at. .ww.com.> on Tuesday July 29 2008, @05:29AM (#24382419) Homepage

              The so called 'solar constant' is actually 1.367 (that should be enough decimals) KW / square meter.

              The actual power produced depends on the angle of incidence (lattitude) and the local weather (cloud cover).

              The current crop of commercially available solar cells hovers around 16% efficiency when new, the best lab models do 40%+ ( http://www.doe.gov/news/4503.htm [doe.gov] ).

              Then of course there's concentration and all kinds of tricks to capture that power in a different form than electricity, and here the efficiencies can be considerably higher still. Electricity is the 'steak' of the power industry, but there are plenty of uses for 'burger' (heat).

        • by Eivind (15695) <eivindorama@gmail.com> on Tuesday July 29 2008, @03:16AM (#24381775) Homepage

          True in theory, nonsense in practice. It's ok to think long-term. But it is silly to concern oneself with problems whose first possible date of appearance is many millenia into the future. There are just so many unknowns in such speculation that it is meaningless.

          Geothermal is of that magnitude -- you'd have to tap a thousand times our current energy-use for millenia to even have a measurable impact.

        • by TapeCutter (624760) * on Tuesday July 29 2008, @06:27AM (#24382685) Journal
          "Scary, isn't it? Unless we carefully condense the steam even geothermal energy doesn't solve global warming. And at present, we don't."

          Sorry but you have been misinformed (probably by those who are not geothermal fans). There is no need to condense the steam, yes it's true that H20 is a powerfull GHG but that is only part of the strory. The atmosphere is already more or less saturated with H20 (eg: dew drops form in desrerts every night and evaporate in the heat of the day), adding more H20 won't affect the temprature because it simply falls out somewhere else as rain/dew.

          In other words the total amount H20 in the atmosphere stays relatively constant regardless of how much steam we pump into it.
          • Re: (Score:3, Interesting)

            actually I would use two or even three turbines. Geothermal generally use a closed loop water system.

            two turbines on for high pressure steam, one for low pressure steam. A third turbine like those built in damns for water. The water heading back down to the geothermal source by gravity could generate additional power.

            • > geo-solidification freezing molten magma under the crust and reducing the ***gravity*** of the earth.

              ???

              winks and flicks to next excuse card.

    • by flyingfsck (986395) on Tuesday July 29 2008, @01:26AM (#24381241)
      Uhmm, you do realize that Iceland is a teenie, tiny little dot of an island in the northern ocean do you? The actual amount of energy produced from geothermal sources in Iceland is verrry small and about equal to a single fair sized coal fired (or nuclear) power station.
    • Re: (Score:3, Insightful)

      While very neat, if we did tap geothermal resources nationwide to get up to supplying 25% of our electrical needs within a few decades, we'd still be behind Iceland. According to Wikipedia [wikipedia.org], Iceland generates 26.5 of its electricity from geothermal power. Strange to think that a place called Iceland has so much available heat for power generation. Going a bit astray, has anyone seen the episode of Science Channel's "Eco-Tech" featuring the rooftop windmills [youtube.com] designed by Aerotecture [aerotecture.com]? Pretty cool.

      26% of Iceland's electrical needs is a tiny number compared to 25% of America's needs. Saying we would still be behind Iceland seems inappropriate if you take into consideration the modest 300k population of Iceland probably consumes less electricity than Baton Rouge, LA.

    • by meringuoid (568297) on Tuesday July 29 2008, @03:46AM (#24381935)
      Strange to think that a place called Iceland has so much available heat for power generation.

      Legend has it that the name of Iceland is an ancient Viking fraud. Erik the Red sailed out into the ocean beyond Scotland, and discovered two new countries there: one rich and green and worth settling, and one frozen and barren and utterly worthless. He named one Iceland, and the other Greenland; when he got home, all the other Vikings rushed off to claim lands in Greenland, and Erik got to keep Iceland for himself.

      • by meringuoid (568297) on Tuesday July 29 2008, @08:06AM (#24383429)
        After posting this, I fired up Wikipedia and read up on the actual history.

        Iceland had already been settled by Erik's time - he didn't discover it. He was exiled from Iceland because of some killings with which he was closely associated, and he sailed away to the northwest, where the existence of land was rumoured but unconfirmed. It's true that he gave it the name of 'Greenland' for marketing purposes, hoping to encourage settlement there, but during the Mediaeval Warm Period Greenland wasn't quite as inhospitable as it is today, so we cannot fairly accuse Erik the Red of fraud. Only murder. But he was a Viking, so that's to be expected.

    • Re: (Score:3, Informative)

      Iceland generates 26.5 of its electricity from geothermal power.

      And of course 73.4% is from hydro power, and only 0.1% from fossil fuels. (probably generators at very remote locations?)

      So the only fuel they import is to power vehicles!

      Now if only they could find a way to export electricity, they would be loaded beyond belief.

    • Re: (Score:3, Funny)

      Greenland used to be green, and Iceland used to be covered in Ice, but then the automobile and the carbon credit were invented, and the environment (which had never changed previously) suddenly reversed itself, and now their names are but mocking jokes to man's care taking of the planet.

    • The key to generating useful power is the temperature difference between the heat source and what you're cooling with. As the climate gets colder, the source of heat doesn't have to be as hot to get economically useful amounts of power. See, for example, here [popularmechanics.com]: "A binary system just requires a heat source and sink: 165 F water can produce electricity if the ambient air or surface water temperature is at least 100 degrees lower. While that may be tough to find in the deserts of Nevada, in Alaska cold air and water are abundant resources."

      Same applies to Iceland, of course.

      • by ColdWetDog (752185) on Tuesday July 29 2008, @12:26AM (#24380889) Homepage
        Win! Yep, that's what's odd about this push by the Alaskan government. The closest volcano to Anchorage (the only real city in Alaska, sorry Fairbanks but it's true) is about 100 km. Now, you can certainly run transmission lines over 100 km, but this isn't your normal, everyday terrain. It's deep water, big mountains and moose.

        Even if you succeeded in running Anchorage off geothermal, what the hell are you going to do for the rest of the state? At best, this is a ploy to get more resources into the Mat-Su valley [wikipedia.org] which isn't all that bad, but I don't see this as a big starter for most of the state or, more generally, for down South (ie, everywhere else). Powerlines to Seattle would cost an awful lot of money.

  • Volunteers? (Score:4, Funny)

    by Tablizer (95088) on Monday July 28 2008, @11:50PM (#24380623) Homepage Journal

    So, how many virgins per minute does it require to keep going?

  • Geyserville, CA (Score:5, Interesting)

    by cathector (972646) on Tuesday July 29 2008, @12:03AM (#24380691)

    i was surprised to read that The Geysers, just north of San Francisco, claims to be "the largest complex of geothermal power plants in the world" [geysers.com]. i guess "largest" is open to interpretation. But here's another startling claim: "The Geysers satisfies nearly 60 percent of the average electricity demand in the North Coast region from the Golden Gate Bridge to the Oregon border".

    who knew ?

    • Re: (Score:3, Insightful)

      That single setup produces about 5 times more geothermal energy than the much touted Iceland...
      • Re: (Score:3, Informative)

        In 2005, 5.0% of Californiaâ(TM)s electric energy generation came from geothermal power plants. This amounted to a net-total of 14,379 GWh. In 2005, California's geothermal capacity exceeded that of every country in the world. California currently has 2492.1 MW of installed capacity, with more under development. http://www.geo-energy.org/information/plantsNow/ca/CA.asp [geo-energy.org]
  • by yorkshiredale (1148021) on Tuesday July 29 2008, @12:06AM (#24380719)
    Anyone else noticed that Iceland is quite a green and verdant place, while Greenland is a large lump of ice?
    • by cathector (972646) on Tuesday July 29 2008, @12:12AM (#24380767)

      not sure i would say "quite" green and verdant. "occasionally", sure. joke i learned from some icelanders: "What should you do if you get lost in an Icelandic forest? ... Stand up."

      • Re: (Score:3, Informative)

        I think the Vikings/Erik the Red named it that to try to con people into living there after realizing Iceland wasn't such a great name for people seeking warmer temperatures or a better place to live than Scandinavia. It wasn't like you could just log onto the web or visit a travel agent back then to check the regional climate of Greenland, heh heh.
  • Works in Hawaii... (Score:4, Interesting)

    by Anonymous Coward on Tuesday July 29 2008, @01:47AM (#24381319)

    The "Big Island" of Hawaii has a geothermal plant rated at something like 25-35 megawatts, which is a meaningful fraction (though not 25%, maybe more like 10%) of demand. More geothermal could be exploited, but there are issues of land ownership (lots of the volcanic stuff is federal land) as well as cultural, religious and environmental sensitivity.

  • Great News (Score:5, Funny)

    by MrKaos (858439) on Tuesday July 29 2008, @01:52AM (#24381345) Journal
    The oil industry will need a cheap form of electricity to extract all that expensive oil. Awesome.
    • Yellowstone (Score:4, Insightful)

      by Telepathetic Man (237975) on Monday July 28 2008, @11:25PM (#24380429)

      Speaking of the lower 48's volcanoes. What about Yellowstone? A super-volcano close enough to the surface that the pressure is bending the crust up. Now there is a prime target for investment. Perhaps we can even vent off enough pressure to reduce the risk of another one of those major blasts that it's known for geologically.

      • Some major right-wing relgious group did in fact install a geo-thermal. But it was shut down. They chose to use direct steam, which potentially would drain the water that feeds old faithful. But I think that a binary system would make sense. That way, the heat is used, not the water.

        Yeah, I have wondered the same thing. It seems that if you lower the temps, it might make it better. Of course, it could make it worse. But hey, do research during the time that we are taking the heat.
        • by Serenissima (1210562) on Monday July 28 2008, @11:58PM (#24380665)
          Well, actually, if you drill a big hole in the ground, you could pipe water down an enclosed pipe. Then the steam would come up another pipe to power generator turbines. When it cools back down to water, you send it back down to heat up again.

          After your initial water investment, you wouldn't really need a significant amount of additional water at all if it was a closed system. I believe that's the general principal in most Geothermal usage wells.
          • Re: (Score:3, Informative)

            Allow that to heat a different carrier,and you have a binary system. That approach is used in Chena Alaska. It allows for lower temps to work. But to be honest, I have been wondering about Johnson's system [johnsonems.com]. Seems like that would do a better job since it bypasses large mechanical systems.
                • by mosb1000 (710161) <mosb1000@mac.com> on Tuesday July 29 2008, @02:41AM (#24381587) Homepage

                  In a heat engine, there is a maximum theoretical efficiency which may be achieved. This is dependent on the difference in absolute temperatures between the hot and cold reservoirs. For example, if your hot reservoir is 1000K, and your cold is 300K, the maximum theoretical efficiency is 1-300/1000 = 70%. In the coal plant you were referring to, the actual efficiency is likely very near the theoretical efficiency (mechanical engineers have done a good job at achieving high efficiencies with mechanical systems). It is impossible to improve upon that without violating the laws of thermodynamics.

                  Of course, no moving parts means that you may be able to operate at much higher temperatures (you'd need a ceramic PEM to sustain the higher temperatures).

    • LOL (Score:3, Interesting)

      Hmmm. So, do a limited resource which is totally unknown, but best estimates of oil are around 10 BBL. IOW, it is just a couple of years worth of oil for America. The humorous part of this is that the oil will simply be sold to Japan or some other place. How long will it last? Maybe 10-20 years. Max. For comparisons, purdhoe bay had 25 bbls. And it is finally running out after 30 years. So, we pump about 1 BBL/year from there.

      And you think that a simple 10BBL is worth a great deal more to Alaska than usi
        • Re: (Score:3, Insightful)

          When it is a closed system, that I would call that clean. The problem occurs when you extract the water and dispose of it on the surface. When it is in the ground, extracted, use for heat, and then re-injected back into the ground, I would say that is clean. OTH, some of these do not operate in that fashion. For example, the one in CA uses waste water from local towns to inject in the ground producing steam. That steam is allowed to flow out. That will pick up the local compounds and send it in the air. B
    • heheheh (Score:5, Informative)

      by WindBourne (631190) on Tuesday July 29 2008, @02:07AM (#24381419) Journal
      That argument is the same one as saying that wind generators wipe out the birds or that CFL have mercury in them.
      Yes, SOME wind generators have killed birds (esp one in CA). But over all have not. More important, these are MUCH better on birds than the pollution being put out by coal plants.
      The same issue with the mercury in CFL. The CFL has a small amount of Mercury, but FAR FAR less than what is put out by a CLEAN coal plant using a regular bulb.

      The geo-thermal requires anywhere from 1 to a 100 holes. But there are plenty of dried wells in places like Colorado that make a great low-temp place (esp, since many wells were already drilled close). Secondly, oil pulls up the exact same sediments. In fact worse, because most are drilling FAR deeper these days. But by using a closed system, esp. with binaries, the pollution on the land and in the air is gone. So that leaves just that below. And since the way of the hole is piping, you really do not interfere with the local water table (barring a shallow heat reservoir). As to the multiple holes, that is also a none issue. Slant drilling works wonders. A single pad with 5 holes will do the trick. Even the EPA says it is one of the cleanest form of energy.