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Power Science

Toshiba Builds Ultra-Small Nuclear Reactor 683

DeusExCalamus writes "Toshiba has developed a new class of micro size Nuclear Reactors that is designed to power individual apartment buildings or city blocks. The new reactor, which is only 20 feet by 6 feet, could change everything for small remote communities, small businesses or even a group of neighbors who are fed up with the power companies and want more control over their energy needs."
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Toshiba Builds Ultra-Small Nuclear Reactor

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  • A slogan (Score:5, Funny)

    by suso ( 153703 ) * on Thursday December 20, 2007 @07:56AM (#21763304) Journal
    Have a fallout, closer to home. Toshiba Micro Nuclear.
    • Sony (Score:5, Funny)

      by Anonymous Coward on Thursday December 20, 2007 @08:05AM (#21763386)

      Have a fallout, closer to home. Toshiba Micro Nuclear.
      Hopefully Sony doesn't get into this business. If you thought exploding laptop batteries were bad, wait until you get a Sony exploding nuclear reactor.
    • Re: (Score:3, Insightful)

      by randuev ( 1032770 )
      there's no cleaner way to generate electricity than nuclear. shame that brainwashing of oil pushing pimps have been so successful.
      • Re:A slogan (Score:5, Insightful)

        by cozziewozzie ( 344246 ) on Thursday December 20, 2007 @08:18AM (#21763508)
        There are many cleaner ways to generate electricity than nuclear. Hydro, geothermal, tidal and wave, wind and solar energy are all cleaner.
        • Re:A slogan (Score:5, Insightful)

          by aurispector ( 530273 ) on Thursday December 20, 2007 @08:29AM (#21763598)
          Sure, but there are plenty of areas where none of the above apply. I live in an area where that is not near any water, has only intermittent sun and wind so another power source is necessary. Geothermal looks great on paper but AFAIK there are still tech barriers involved. Nuke power is certainly better to coal or oil/gas. Coal spews more heavy metals and radioactive material into the atmosphere than nukes ever did. With fossil fuels the mess gets spread all over the planet, with nukes it all stays in one place.
          If you took all the toxins, etc., from coal and condensed them on one place, the greens would have a fit no matter where you tried to bury it.

          Besides, did you turn YOUR air conditioner off last summer?

          Anyway, this will never fly in the US - I can guarantee that the big utilities will lobby congress and FUD it to death.
          • Re:A slogan (Score:5, Funny)

            by Pollardito ( 781263 ) on Thursday December 20, 2007 @09:48AM (#21764426)

            I live in an area where that is not near any water, has only intermittent sun and wind so another power source is necessary.
            these problems are among many that go away when you move out of your parents' basement
          • Re:A slogan (Score:4, Funny)

            by lymond01 ( 314120 ) on Thursday December 20, 2007 @11:33AM (#21765840)
            Sure, but there are plenty of areas where none of the above apply. I live in an area where that is not near any water, has only intermittent sun and wind so another power source is necessary. Geothermal looks great on paper but AFAIK there are still tech barriers involved.

            BUZZES IN: What is the planet Mercury?
          • Re:A slogan (Score:5, Informative)

            by dgatwood ( 11270 ) on Thursday December 20, 2007 @02:08PM (#21768198) Homepage Journal

            Even when they do apply, that's at least partially wrong. Hydro power is about as un-green as you can get. It does more environmental damage than coal.

            Traditional hydro power blocks rivers, which causes problems for fish migration. Hydro power creates pools of water where plant matter dies, releasing large amounts of methane, which contributes directly to global warning. And so on. Hydro power is really relatively nasty stuff. It's fine if you already have a dam for flood control reasons and are just taking advantage of the water flow, but otherwise, it's generally a bad idea.

            Solar power is also nasty, at least if you're talking about photovoltaic cells (the only type of solar power practical for anyone but large power companies). The chemicals used to produce the cells are really horrible for the environment. There are cleaner cell chemistries on the horizon, but AFAIK, nothing in mass production yet. The giant solar tower designs don't have that problem, though they are impractical except for large installations and require substantial energy storage to provide power at night. Depending on the energy storage mechanism used, that can be pretty nasty environmentally as well. If they do use a clean storage mechanism, though, such as storing heated water underground, it is relatively green. Notice, though, that with so many "ifs", a large chunk of solar power isn't green at all.

            Wind power, bird risks notwithstanding, is relatively green.

            Nuclear power is also relatively green. Its only emission is water vapor, which quickly settles out of the atmosphere. The nuclear material, while a waste product, was radioactive on the way in, too. You aren't really producing nuclear waste. You are simply taking advantage of a natural process that would occur inside the ground and harnessing it for power by bringing it up out of the ground. By any sane standard, it is every bit as green as wind power.

            Another one you didn't mention is tidal power. This is pretty different from traditional hydro power, and is generally considered to be fairly environmentally sound, AFAIK. It is also limited to coastal regions, which makes it pretty much useless in large percentages of the world, but it's a start. :-)

        • Re: (Score:3, Interesting)

          by peragrin ( 659227 )
          but are inconsistent and require large land area's worth of stuff, to generate the same mount of power as just one of those little nuclear reactors.

          Wind doesn't always blow, tides come and go, Hydro requires large damns, Solar requires land area in the square mile range, geothermal is limited to areas which have large geothermal activity(iceland, yellowstone).

          Though personally Solar has the best bet for the future. just two technologies need to be perfected. Crank up solar cell effeciency to 30-40%, and
          • Are you kidding? (Score:5, Insightful)

            by professorguy ( 1108737 ) on Thursday December 20, 2007 @08:54AM (#21763802)
            Why don't you come out to my house and install your solar panels on my roof? I'm sure it will be no problem that they are under a few feet of snow for 4 months a year. Or that we get 50 sunny days (on average) a year, half of which are when we have snow. Or that at 44 degrees north, even at the solstice at high noon we have low wattage/area.

            Gee, I guess I'll be selling all my extra power to the grid.

            I love it when someone from Arizona tells me that solar power is going to solve all my power problems here in northern New Hampshire.

        • Re:A slogan (Score:5, Insightful)

          by FireFury03 ( 653718 ) <slashdot AT nexusuk DOT org> on Thursday December 20, 2007 @08:54AM (#21763804) Homepage
          There are many cleaner ways to generate electricity than nuclear. Hydro, geothermal, tidal and wave, wind and solar energy are all cleaner.

          Depends how you define "clean" - hydro power is usually environmentally quite damaging. Tidal power can also be quite damaging if done inappropriately (I'll point at the proposed Severn Tidal Barrage as an example of how do do a lot of damage to the environment through harnessing the tides). Thermal solar based systems are probably pretty clean, but photovoltaic systems use quite a lot of rather nasty chemicals in their manufacture which must be handled carefully (kind of like fission products in fact...)
          • Re:A slogan (Score:4, Insightful)

            by Telvin_3d ( 855514 ) on Thursday December 20, 2007 @09:14AM (#21763982)
            And all that also ignores the realities of the location. Hydro, tidal and wave all have the prerequisite of large bodies of water. Wind needs a location with a reliable breeze. Solar power isn't particularly efficient in many areas that suffer from lots of cloud cover and rain, or long winter months.

            I think on of the biggest problems with the environmental movement (or at least their PR) is that they seem more than happy to pursue perfect solutions at the expense of good solutions.
            • Re:A slogan (Score:5, Insightful)

              by FireFury03 ( 653718 ) <slashdot AT nexusuk DOT org> on Thursday December 20, 2007 @09:38AM (#21764270) Homepage
              I think on of the biggest problems with the environmental movement (or at least their PR) is that they seem more than happy to pursue perfect solutions at the expense of good solutions.

              I agree entirely. Although the other problem seems to be that they take a solution that might be more or less perfect, given perfect conditions/location and push it so hard they end up putting it in conditions/locations where it either doesn't work or causes a lot of damage. I'm all for installing in "renewable" power generation systems where appropriate, but I also recognise that they are often not appropriate and that fission is a pretty good solution (with appropriate handling and reprocessing facilities for the spent fuel).

              Also, whilst I can forgive the general public for overreacting based on misinformation (e.g. the "nuclear is bad" attitude caused by its association with nuclear weapons, Chernobyl, etc.), it seems that the big environmental groups who attract the media's attention are often just as badly informed. For example, Greenpeace is opposed to ITER and other fusion research, stating that it is dangerous, a waste of money and that it should be spent on renewables instead. So they seem to not want research into a technology that could producer cleaner (although not completely clean) energy. Yes, we may never get useful power out of fusion reactors, but we won't know until we try - I for one am hopeful.
        • Re: (Score:3, Insightful)

          by innerweb ( 721995 )

          Whether or not these are *greener* is open to debate. They all have serious consequences as well. Some eat of land, removing it from its natural form and use. Some flood large areas of land, again destroying its natural use, and destroying the original aquatic use. They all modify the area in which they are used. Geothermal is probably the one with the least known consequences of all, but I am not holding my breath once we start dealing with leaks in a geothermal system at its lowest points. There i

      • by Knuckles ( 8964 )
        There's also no more sure-fire way to increase the power of the police and military. Well, except a terrorism scare.
    • Good luck purchasing the enriched uranium needed to run your private building block reactor.

      Or operating the thing yourself.

      It's an interesting technology, but the chances of having one of these for your apartment are not very good.
      • Re:A slogan (Score:5, Interesting)

        by Firethorn ( 177587 ) on Thursday December 20, 2007 @09:07AM (#21763916) Homepage Journal
        Good luck purchasing the enriched uranium needed to run your private building block reactor.

        Toshiba manages that

        Or operating the thing yourself.

        No need, it's completely automated. The only thing you worry about is putting water in one end and running the steam through the turbine on the other.

        It's an interesting technology, but the chances of having one of these for your apartment are not very good.

        It'd be expensive overkill, yes. Now, a few for the local military base... I mean, they already have highly enriched uranium buried all over the place...

        Might as well save a few million(and let the local coal plant off the hook a bit).

        Wait a second...

        Let's say that this is a large apartment complex. 200 apartments. Each apartment averages ~8 amps, 1kw each. At 10 cents per kwh, that's $73 each, average bill*. We buy/sell electricity to the grid to balance load just like most people with solar panels(net metering). Selling electricity at 10 cents a kw/h to our tenants is more than enough to cover the cost of the plant. Heck, we break even if we can sell it to the power company at 5 cents.

        Still, this reactor system isn't going to be 100% efficient at turning heat into electricity. Since we have the heat source on site, we build a trigeneration [cogeneration.net] plant [wikipedia.org] instead of a straight electricity generator that also heats the water for use in the apartments, runs a building heat system of some sort, and utilizes an absorbtion cooler to provide AC.

        This should allow me to sell electricity to my tenants and the grid to cover the cost of the reactor, and provide heating & cooling to by tenants for essentially the cost of the generation equipment. Heating and cooling can easily equal the electricity cost, so the potential profit is high. At the very least, the lower costs would allow me to offer a lower rent price to keep the apartments full while still offering perks such as 'heat, AC, and hot water included!'.

        *Just assume that they're running around with inefficient electric appliances and use their electric stove a lot.
    • Re: (Score:3, Funny)

      by bigjocker ( 113512 ) *
      A better slogan: The only reactor that lives in 2D space! You can paint it in the wall!

      The new reactor, which is only 20 feet by 6 feet
  • by LiquidCoooled ( 634315 ) on Thursday December 20, 2007 @07:57AM (#21763306) Homepage Journal
    Someone should have told these [computerworld.com.au] students that they could get one of these and not have to peddle.
  • Incredible. (Score:5, Funny)

    by Spazntwich ( 208070 ) on Thursday December 20, 2007 @07:57AM (#21763310)
    How did they manage to shrink a nuclear reactor to only two dimensions?
    • Re:Incredible. (Score:5, Informative)

      by Firethorn ( 177587 ) on Thursday December 20, 2007 @08:09AM (#21763412) Homepage Journal
      20 feet high, 6 feet in diameter.

      Oh, and this is old. I believe it was around 3 years ago that I first heard of this. They were talking about installing one in a remote village up in Alaska that gets all it's power from diesel because it'd be too expensive to connect it to the grid it's so far away.

      Then the greenies* heard about it and killed it. The villagers were pretty much all for it.

      *Can't really call them NIMBY, unless they count the entire planet their backyard in this case.
      • Different reactor (Score:3, Informative)

        by Xelios ( 822510 )
        The one from 3 years ago was Toshiba's "4S" reactor ("Super-Safe, Small and Simple") designed to produce 10MW of power (much more than this new "micro reactor"). In other words the 4S is a real nuclear plant (albeit a small one), complete with a small staff to run it. Wikipedia link [wikipedia.org].
  • Yup (Score:5, Insightful)

    by FictionPimp ( 712802 ) on Thursday December 20, 2007 @07:59AM (#21763330) Homepage
    I'm sure the US government would have no problem with people buying these, no problem at all.
  • by Albert Sandberg ( 315235 ) on Thursday December 20, 2007 @08:00AM (#21763338) Homepage
    now they don't have to rely on bicycles for the supercomputer energy needs!
  • Growing up I always loved to take things apart. Everything... My Toys, my parent's stuff like the Kaypro we had, and the Apple II... After I saw this over at engadget earlier and now here, I must say I am glad I am not a kid anymore. I would have taken this sucker apart if we had one and probably set myself on a course to be my own nightlight. Although I do like the cost associated with these things, I always like lower electric bills. However, I fear the kid that wants to see how it works or the hick
  • From TFA

    Toshiba expects to install the first reactor in Japan in 2008 and to begin marketing the new system in Europe and America in 2009.

    Now THAT should get interesting
    • by afidel ( 530433 )
      Yeah my problem with this concept is what percentage of the world doesn't have to potential for SOME kind of natural disaster? Japan has earthquakes and typhoons, most of the world has at least some chance of tornado's, etc. Unless these thing are designed to take 300mph hits by large object and a large building falling on them I can't see how regulators can possibly allow them to be sold.
    • by hey! ( 33014 )
      "Marketing" isn't the same as "installing".

      That said, there are good reasons why such systems would be easier to license than a full sized reactor. For one thing, they can be leased, and when they're at the end of their useful lifespan the company takes them back. It doesn't solve the nuclear waste problem, but it at least identifies who is responsible for clean up (although I'd make them post a bond to make sure disposal/recycling is paid for).

      In any case, I don't think we'll see every apartment block wi
  • Lifetime cost (Score:2, Interesting)

    by tomalpha ( 746163 ) *
    40 years x 365 days x 24 hours x 200kW x $0.05 = $3.5bn

    Ok, so I guess it wouldn't run at full capacity all of the time, but even if you half it, or quarter it, it's still a big number.

    Slightly more silly: if you were to use the MIT students from the previous article [slashdot.org] and you assumed they worked 24 hours a day to produce 200kW, and you paid them $10 an hour you'd need 1600 of them and it would cost $5.8bn over the same time period.

    I guess that's why we have nuclear power.
    • Re: (Score:3, Insightful)

      by close_wait ( 697035 )
      That should be $3.5M. A lot cheaper than students.
    • Re:Lifetime cost (Score:5, Informative)

      by slashqwerty ( 1099091 ) on Thursday December 20, 2007 @08:18AM (#21763500)
      40 years x 365 days x 24 hours x 200kW x $0.05 = $3.5bn

      I think you're off by a factor of 1000. I get $3.5 million. That's far more practical. You're numbers come out to $50/kWh.

    • Huh, I only come up with 3.5 million.

      I thought your figure looked wrong because a full scale gigawatt nuclear reactor would be expected to cost around the same amount during that time, depending on figures ($1B-3B in construction, some for more for overhead).

      I think you multiplied by 200,000 instead of 200. Remember it's .05 per kilowatt hour. This nuclear plant produces 200 kilowatts, so it cancels out.

      It's about double the cost of a conventional nuclear plant, but as noted, it's extremely small scale, s
      • Re: (Score:3, Interesting)

        by Tony Hoyle ( 11698 )
        There's the waste disposal cost and the decommissioning cost to add to that as well. Nuclear waste is hellishly expensive to transport and dispose of... offseting the gains you get from the cheaper power generation. Decomissioning can eat up more money than building the thing in the first place.

        • Re: (Score:3, Insightful)

          by kestasjk ( 933987 )
          The cost of decommissioning is actually factored in to the electricity price, as anyone who's not a rabid anti-nuclear fanatic would assume.
  • I'll wait for the eventual smaller form factor in a year though. Gives me time to save for a Delorian. Those flux capacitors [shopneo.co.uk] don't seem so extraneous right now.
  • Fuel (Score:3, Interesting)

    by ChowRiit ( 939581 ) on Thursday December 20, 2007 @08:07AM (#21763394)
    How are they planning on fuelling these reactors? I somewhat doubt, with current paranoia about terrorist "dirty bombs", that they'll be willing to use uranium, which seems to me to somewhat defeat the point of a nuclear reactor...
  • Self contained (Score:4, Insightful)

    by olman ( 127310 ) on Thursday December 20, 2007 @08:08AM (#21763402)
    I wonder if their cost/kWh figures includes Greenpeace terror campaign against nuclear anything..
  • ominous (Score:5, Funny)

    by mincognito ( 839071 ) on Thursday December 20, 2007 @08:08AM (#21763404)

    The new reactor, which is only 20 feet by 6 feet, could change everything for small remote communities, small businesses or even a group of neighbors
    I think that's the worry.
  • Cannot Find (Score:5, Informative)

    by russ1337 ( 938915 ) on Thursday December 20, 2007 @08:09AM (#21763416)
    I heard about this yesterday, and searched the Toshiba's main website for a press release or anything. I found nothing beyond the article. If Toshiba are really doing this, i thought it would at least be a headliner on their website.

    Anyone?? I'm wondering if this is even real.

    my search here [google.com] (you may have to filter for medical results)
  • Wow, now its not-in-my-backyard but not-in-the-basement-of-my-apartment.
  • by Zarhan ( 415465 ) on Thursday December 20, 2007 @08:14AM (#21763464)
    Lots of advocates for solar/wind/other renewables oppose using nuclear power to help against global warming because "They come in only one size: Extra large". This one pretty much mitigates that argument. Of course, Toshiba has done this before, with the Galena project [wikipedia.org]...looks like they are really pushing miniaturization of nukes.
  • I'd be wary of any story from this source, what with all its links to "overunity" and "free energy" sources. Where's the corroboration from Toshiba?
  • I seem to recall reading an article in Wired several years ago about pebble-bed reactors, and building them small enough that each town could have their own. Maybe even small enough that you could run one just for your house, or yourself and a few neighbors. I think someone wanted to pilot such a program in China.
  • I always wondered whether a nanoscale reactor is possible - it's be great, too small and complex to be unloaded and the fuel spent elsewhere, but possible to generate quite a bit of power, especially if lots are coupled together.

    IANANPh, but I'd guess there'd be problems with shielding as I don't think radiation scales very well, but I could be wrong... anyone know?
  • aren't these the same guys that make the batteries that keep blowing up?
  • Would you have one of these in your cellar? I wouldn't. I'd rather tune down my power consumption by a magnitude and switch to solar energy or something. I don't think this will fly.
    • Would you have one of these in your cellar?

      Have one myself? Not likely, but possible. Wanting my dumb-ass neighbors to have one? No way.
    • Solar is not viable in high latitudes as the same winter that makes more difficult to have hydro (because water freezes) or thermo-electric (because you have to haul the fuel from somewhere) generation also makes the daylight last few hours.

      Low-service nuclear is the way to go in these cases.

      If I had to live off-grid, I would rather have solar or solar-thermal where I live (a mile south from the Tropic of Capricorn), but nuclear also seems a nice option for "power-anywhere problems".
    • ] wouldn't. I'd rather tune down my power consumption by a magnitude and switch to solar energy or something. I don't think this will fly.

      Temperatures this past summer held in the mid nineties with 80% humidity. Winters can be just as brutal with lows near zero and winds gusting to fifty. You are going to find very tough to lower your power consumption "by an order of magnitude" under those conditions. There are no easy or obvious alternatives for the neighborhood, the nursing home, the single family re

  • Moon or mars (Score:3, Insightful)

    by WindBourne ( 631190 ) on Thursday December 20, 2007 @08:38AM (#21763662) Journal
    Something along this design could be used on the moon or mars. It would be nice to have guarenteed power there with 40 years lifespan. But it would be nice to see MW, rather than KWs.
    • Re: (Score:3, Interesting)

      And note how this comes just as ion thrusters are becoming common in space exploration. Dawn was launched just months ago and is propelled by ion thrusters, for example. 200 kW for 40 years is exactly the right order of magnitude that's interesting these days. I'm not sure exactly how much power Dawn uses for thrust, but it can make 10 kW, this would give 20 times more. This might seem like an overkill, but it might be usefull when visiting the outer planets moons, since you can carry enough propellant to g
  • by hey! ( 33014 ) on Thursday December 20, 2007 @08:41AM (#21763686) Homepage Journal
    The claimed cost of power is $0.05/kwh.

    A gallon of gasoline has something around 35kwh. 35kwh from this thing would cost you $1.75. If you had a fleet of electric vehicles, you could continually charge batteries off this thing and swap them out.

    A 200kw reactor would produce the equivalent of almost 140 gallons of gasoline per day. Effectively this is more energy, if your vehicles operate in the city, because you don't expend energy idling the engine. You could operate a fleet of electric cabs, locking in the equivalent of a $1.75/gallon energy cost for the next forty years.
  • Warning... (Score:5, Funny)

    by Pedrito ( 94783 ) on Thursday December 20, 2007 @08:58AM (#21763838)
    I got one of these and, honestly, it only puts out about 180 kilowatts out of the box. I managed to overclock it to 250 kilowatts, however. I just finished the case mod. I'm using plexiglass so you can see what's going on inside. It also weighs a lot less without all the lead, which was pretty unattractive. But now Toshiba is saying I voided my warranty and won't give me tech support. I just want to find out why my dog started glowing in the dark...
  • by savuporo ( 658486 ) on Thursday December 20, 2007 @09:13AM (#21763966)
    http://www.world-nuclear.org/info/inf82.html [world-nuclear.org]

    So the USSR, US and french have designed and built small spaceworthy reactors before. Some of these things have flown on actual space missions, particularly the russian Topaz-I system, weighing only 320kg.

    They even built and tested nuclear powered aircraft both in US and USSR
    http://en.wikipedia.org/wiki/Nuclear_aircraft [wikipedia.org]

    Wonder why it never went anywhere ?
    • by caffiend666 ( 598633 ) on Thursday December 20, 2007 @01:04PM (#21767050) Homepage

      Because one of the test teams died miserable deaths: http://en.wikipedia.org/wiki/SL-1 [wikipedia.org] . They found one engineer pinned to the roof several days later.... "The third man was not discovered for several days because he was pinned to the ceiling above the reactor by a control rod. On 9 January, in relays of two at a time, a team of eight men, allowed no more than 65 seconds exposure each, used a net and crane arrangement to recover his body.

      The bodies of all three were buried in lead-lined caskets sealed with concrete and placed in metal vaults with a concrete cover. All had major physical injuries, including severed limbs and fragments of the fuel assembly in their wounds. Richard Leroy McKinley is buried in section 31 of Arlington National Cemetery."

      The radiation levels were too high for the rescue teams to get near the reactor and figure out what happened. After they recovered one body, they use the radation levels of his body and the rare isotopes they found on his possessions (Gold 198 anyone?) to prove the reactor had gone super critical.

      Much nuclear space research was put on hold after the effects of the Starfish Prime experiment were understood.

  • by whoda ( 569082 ) on Thursday December 20, 2007 @09:26AM (#21764128) Homepage
    10 years ago, this article would have abounded with threads on how cool this is, and "I wonder if you could make a Beowulf cluster of those."

    Now, it's all, nuclear is bad, nuclear is evil because "The terrorists might get it".

    Listen to yourselves. You've eaten the terrorist propaganda the government has been feeding you, AND YOU LOVE IT.
    "We can't do this because it might help the terrorists."
    "Yeah, that's cool, but what about the terrorists?"
    "If it weren't for terrorists, this would be awesome."

    George Bush loves you guys, he's got you on his side and you don't even realize it.

  • Submarines (Score:3, Interesting)

    by rockmuelle ( 575982 ) on Thursday December 20, 2007 @09:27AM (#21764142)
    Submarines have had very small, very safe reactors for decades. Unfortunately, the technology is highly classified and will most likely never be made available for commercial uses

    My brother-in-law was on an attack sub and I got to tour it (my father in-law actually got to drive it!). We weren't allowed aft passed a certain point, but give where we were in the sub, you could get an idea of how small the reactor was. Always thought it would be fun to put those reactors to use for domestic power generation, even if just for special purposes like powering server farms.

    -Chris
    • Re: (Score:3, Informative)

      by hcdejong ( 561314 )
      The nuclear plant in a sub takes up something like 1/3 of the internal volume. this page [fas.org] quotes the size and weight of the plant in a Los Angeles-class sub as 1600 tons, with a volume of 42 (length) x 33 (diameter) feet. Its heat output is ~160 MW, part of which is used to drive a 35000 shp turbine.
      Now, the reactor itself is just a fraction of this volume. The data are classified, but as a comparison the reactor in Dodewaard (an experimental nuclear plant in the Netherlands, decommissioned a few years ago,
  • http://en.wikipedia.org/wiki/Toshiba_4S [wikipedia.org]

    The 4S uses neutron reflector [wikipedia.org] panels around the perimeter to maintain neutron density. These reflector panels replace complicated control rods, yet keep the ability to shut down the nuclear reaction in case of an emergency. Additionally, the Toshiba 4S utilizes liquid sodium as a coolant, allowing the reactor to operate 200 degrees hotter than if it used water. This means that the reactor is depressurized, as water at this temperature would run at thousands of pounds per square inch.

    This is interesting. As stated in the previous nuclear reactor article entitled "China goes Nuclear" [slashdot.org], uranium is kept in small pebbles made of graphite, which is a neutron reflector material.

    Both reactor designs have a "negative temperature coefficient of reactivity" simply means that an increase in core temperature will cause a decrease in core power. If the temperature increases too much, the core will shut down. I don't know if the pebble-bed design does, but the 4S still produces heat after being shot down (I'm not sure if the pebble-bed reactor does), so there must be some mechanism provided to remove the generated heat.

    More interesting facts: pebble-bed reactors [wikipedia.org] use helium as coolant instead of water, and helium is much more resistant to becoming radioactive - this deals with the possibility of having a radioactive cloud in case of an accident. The 4S, in comparison, uses liquid sodium as coolant [wikipedia.org], allowing the reactor to operate 200 degrees hotter than if it used water. This means that the reactor is depressurized, as water at this temperature would run at thousands of pounds per square inch.

    However, I'm not sure how safe sodium is, and we all know what happens when sodium comes in contact with water [youtube.com] - and heated sodium explodes just as easily [youtube.com] when it's exposed to air. Helium, instead, is an inert gas.

    IANANS (I am not a nuclear scientist), but the pebble-bed design seems very well-thought, requiring less control mechanisms than the 4S, so I think I'd go for the pebble-bed design.

    Is there any nuclear scientist around to give more info and comparisons, and correct any mistakes I may have made?
    • by SixFactor ( 1052912 ) on Thursday December 20, 2007 @11:28AM (#21765772) Journal
      Spy,

      To address your points:

      "...uranium is kept in small pebbles made of graphite, which is a neutron reflector material."

      Technically, graphite is a neutron moderator, to allow the neutrons to slow down and interact with other nuclei in the fuel matrix. The Chicago Pile 1 used the graphite bricks as the moderator matrix. The downside of graphite is that if a graphite fire starts, it's very difficult to put out. So the pebble bed isn't quite the ideal, IMHO.

      "Both reactor designs have a "negative temperature coefficient of reactivity" simply means that an increase in core temperature will cause a decrease in core power. "

      This is but one part of current regulatory requirements. The General Design Criteria [nrc.gov] govern the design of nuclear plants in general, and cores in particular. The downside of having too strong of a negative temperature coefficient is that in an overcooling scenario, you get the opposite effect. This is why Main Steam Line Breaks are considered in the core design.

      "More interesting facts: pebble-bed reactors use helium as coolant instead of water..."

      Personally, I've always liked the gas-cooled (especially He) reactors. BTW, this has been done before at Fort St. Vrain in Colorado. Unfortunately, because it was a first of a kind (here in the US, anyway), it was plagued by more mundane issues, like seal leakage, etc. Nothing catastrophic, but a pain in the ass operationally.

      Sodium on the other had was intended to minimize the impact of metal corrosion. Think about it: with a liquid metal coolant, the fuel, piping, etc. would maintain integrity pretty well. The bad thing is that yes, Na is a dangerous thing to deal with - especially on a large scale. The Experimental Breeder Reactor in Idaho was one such, I think. This is where a lot of the operational problems were discovered.

      We learn by doing.

      Hope this helps.
  • More info (Score:5, Informative)

    by Xelios ( 822510 ) on Thursday December 20, 2007 @09:47AM (#21764410)
    After crawling the web a bit I found a few more interesting links about Toshiba's "Micro-Nuke" technology. First an article from 2005 [primidi.com] about a similar Toshiba reactor running on liquid Sodium that was slated to be installed in a remote Alaskan village some time before 2010. This doesn't appear to be the same reactor as mentioned here on /.

    A blog entry [blogspot.com] with more information and links about this and other small reactors.

    It seems to be fairly safe, though I can't imagine the red tape they'll have to get through in order to begin installing them, especially in North America. The Nuclear Regulatory Commission in the US has about a 60 month process to certify a reactor from the time the application is filed, Toshiba probably has a head start on this application from 2005 with its "4S" mini-reactor, but this new Lithium version will probably need its own application process. They plan to build these things at least 30m underground, encased in steel and concrete walls that probably put most bank vaults to shame, so I don't think tampering will be a major issue.
  • by Ancient_Hacker ( 751168 ) on Thursday December 20, 2007 @09:52AM (#21764498)
    Hmm, yet another mostly ridiculous article, if you know anything about nuclear technology.
    • Reactors don't scale down very well. The surface area (through which you lose neutrons) goes down slower than the volume (which creates the neutrons). Anything below a Fermi-1 size reactor, you need enriched uranium ($$$$$$). For a car-sized reactor, you need highly enriched uranium ($$$$$$$$$$$). That's not only expensive as heck, but a bomb-maker's dream. LIthium as a reflector helps some, but not al that much, and has its downside too.
    • A few small reactors have been made. One scaled-down model for the NR-1 submarine cost about $60 million, and puts out almost 80 horsepower. Another scaled down one, for the Artic, called the SL-1, cost a bit less, but did not last very long, even with continuous maintenance, and finally blew up real good, (probably due to a careless Joe).
    • You need at least a couple skilled engineers, not to mention a few guards, to deploy a power station. Not exactly economical for a power plant that only makes a few dollars per hour of electricity.
    • A small reactor, especially one without a thick containment, is going to be easy pickings for terrorists. A thick containment dome is surprisingly expensive, making the alleged cheapness of the basic reactor quite irrelevant.
    • Technologies like "Pebble bed" and "intrinsically safe" reactors have been the stuff of Popular Science magazine for decades now. Not likely any of them will get built any time soon, for many very good reasons.
    • Re: (Score:3, Insightful)

      by rtechie ( 244489 )

      Reactors don't scale down very well. The surface area (through which you lose neutrons) goes down slower than the volume (which creates the neutrons). Anything below a Fermi-1 size reactor, you need enriched uranium ($$$$$$). For a car-sized reactor, you need highly enriched uranium ($$$$$$$$$$$). That's not only expensive as heck, but a bomb-maker's dream. LIthium as a reflector helps some, but not al that much, and has its downside too.

      Utter nonsense. There are nuclear-powered wristwatches. The nuclear-powered pacemaker, which was safe enough to IMPLANT IN PEOPLE'S CHESTS, has been around for 40 years. Yes, they require relatively expensive fuel. Weighed against it's power density and longevity, enriched uranium is fairly cheap. Plutonium, like they used in the pacemakers, *IS* quite expensive. But even plutonium isn't that expensive given it's power density. The lithium-oxide batteries that replaced plutonium in pacemakers cost nearly 1

  • by Quintin Stone ( 87952 ) on Thursday December 20, 2007 @10:19AM (#21764852) Homepage

    Unlike traditional nuclear reactors the new micro reactor uses no control rods to initiate the reaction.

    Anyone who knows anything about nuclear reactors knows that control rods certainly do not initiate reactions. They regulate or halt it by absorbing the neutrons that cause it. Maybe the author at "Next energy news" should become a bit more familiar with his/her subject before writing about it.
  • by anorlunda ( 311253 ) on Thursday December 20, 2007 @11:05AM (#21765434) Homepage
    There were a number of building size reactor designs proposed in the 1980s.

    I once worked for a company that designed an intrinsically safe urban reactor designed to make hot water. We had convinced the city of Helsinki to buy it and were within hours of signing the contract when the Chernobyl Reactor accident occurred. Helsinki would have used it as a district heating plant big enough to heat all the buildings in the city.

    Nuclear reactors are much better at making hot water than they are at making electricity. Heating is a major consumer of energy in many locations. Therefore, replacing a fossil fuel heat source with a nuclear heat source is more beneficial to the environment than replacing an electric power generator. There are other applications, aluminum smelting for example, that need copious quantities of heat, not electricity per se.

  • by sinktank ( 871915 ) on Thursday December 20, 2007 @11:10AM (#21765510)

    I can just imagine the operating manaul:

    "Thank you to use Nuclear-Friend. The main characteristic in machine of control rod moves in with slim middle, can nimble neutron dependable work send, of via sea warmness thusly turbine twist out machine-wind.

    ALERTNESS, magnet-imprison with ionisation threatening badass. Fleeting bioluminescence in bird appendage observation, conjunction Cherenkov neon likeness, linking chain of no command (barking!) to blinking indications. Personages of vicinity ascending fucking with sparks! Ability detriment remove with "fast-neutron-sheilding-blanket" (slowly neutrons with alacrity) to mammalian sex babylove machine faulty. As packing box inside includes dosimeter for life-spirit guard dog is. Un-normal witness with e=mc2 of cloudy fungus c.10km bigness, warranty glue not connected."

  • by HPNpilot ( 735362 ) on Thursday December 20, 2007 @01:12PM (#21767170) Homepage
    Any nuclear reactor, by definition, must use radioactive material. This material can be used to make a "dirty" bomb, thus, all such material is highly regulated by the US Government. Some apartment building will NOT be allowed to have one of these. The security that would be required would price it right out of the market. Perhaps one could be built under the police department in a good sized city?

    One could make a logical argument regarding the true danger posed by a dirty bomb, but the US Government seems to have completely abandoned logic as a basis for any of their actions.

    The Islamists of the Middle East, who have the largest share of the world oil reserves, seem to have conveniently made it very difficult to get approval for their main energy competitor. In the end we may come to understand that their objective is financial rather than ideological.
  • I Just Knew... (Score:3, Interesting)

    by eno2001 ( 527078 ) on Friday December 21, 2007 @10:24AM (#21779190) Homepage Journal
    ...that's where we were headed. What a stupid idea. It's like giving people PCs. They have more computing power than they actually need. They waste more power because it's inefficient. They cause more problems because they are clueless about maintaining their PCs and get rooted more times than I care to imagine. They are stupid enough to take their PCs in for repair at big box shops that employ neanderthal techs (not all of them, but most of them are stupid goons) and then pay an arm and a leg for a completely reformatted system at best and a poorly patched system at worst. But most of all, these people who seem to think they need all this computing power do VERY little with their systems and probably use about 3% of what the systems are capable of. Now apply that to local power generation paying attention to the fact that a reactor need fuel and careful maintenance:

    They have more electrical power than they actually need. They waste more electrical power AND nuclear fuel because a reactor for a small group of homes is inefficient. They will cause more problems (explosions, radioactive contamination) because they are clueless about properly maintaining their nukes and will likely come very close to meltdowns more times than I care to imagine. They will be stupid enough to trust the repair and maintenance of their nukes to companies that will employ neanderthal techs who are poorly paid and have little care for making mistakes. (Hell, if a phone company can blow up a house by hitting a gas line [this happened in Strongsville Ohio in August 2007. Look it up.] and very likely shirk all responsibility, you can just imagine what the private sector will do with nuke maintenance) But most of all, these people who seem to think they need locally generated power for their cul de sac will like use VERY little of the power generated and the rest will be wasted in the name of convenience.

    Yes, I believe that energy companies are vultures and most of the CEOs and administration in those companies should be lined up against a wall... But I also think that part of the equation to really being smart about electrical energy consumption comes down to conservation. Instead of Toshiba making nukes as a first line of energy crisis solutions, they should instead be working on ways to make their devices more power efficient. Even if it means INCONVENIENCE for the end user. ALL of the consumer electronic companies should be doing this. Make sure all devices actually turn completely off and drain NO power when a user is not using it. Make sure that all computing devices that need to have a saved state do so with solid state drives and better battery technology. Re-work home computing so that all you need is one central resource module that hosts CPU, RAM and storage and interacts with wireless devices that are the "terminals" or "thin clients" while still providing something that feels like a regular PC experience. Make sure that one central module does NOT run an OS at all, but simply hands out resources to the authorized devices. That way you can buy one decent unit that might last a decade instead of new PCs every two to three years. And GET USED TO INCONVENIENCE. It's better than destroying the planet. I'll happily ride the bus to work instead of drive if it means I'm one less polluter. (I do ride the bus to work for just that reason) If you can't bring yourself to inconvenience yourself, you've failed in your civic duty to others.

One good reason why computers can do more work than people is that they never have to stop and answer the phone.

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