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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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  • Re:Incredible. (Score:5, Informative)

    by Firethorn ( 177587 ) on Thursday December 20, 2007 @09:09AM (#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.
  • Cannot Find (Score:5, Informative)

    by russ1337 ( 938915 ) on Thursday December 20, 2007 @09:09AM (#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 [] (you may have to filter for medical results)
  • Re:Lifetime cost (Score:5, Informative)

    by slashqwerty ( 1099091 ) on Thursday December 20, 2007 @09:18AM (#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.

  • Re:Fuel (Score:4, Informative)

    by Total_Wimp ( 564548 ) on Thursday December 20, 2007 @09:34AM (#21763628)
    "TFA says it'll use lithium-6."

    I don't think that's what it said. I think it said the lithium was a replacement for control rods to absorb neutrons and keep the nuclear reaction under control. I don't think the article specified the fuel at all.

    Now I am not a nuclear reactor engineer nor a physicist, so if you know more about how this works it would be great to get a better explanation than the one the very short article gave.

    BTW, never trust anyone who says "nothing can go wrong with it." Something can always go wrong. If they say "these are the risks, but we've assessed them and their mitigating factors and we ultimately believe the ristks aren't big enough to cause concern," you can start paying attention again.
  • by Anonymous Coward on Thursday December 20, 2007 @09:41AM (#21763684)
    You must be american. Letting unscientific fear rule your opinion.
    It's actually quite safe. Here safe meaning in the same sense that cars are safe, even though their engines are in a near constant state of explosion.
    We have come quite a far way since the days when nuclear reactions where unstable accidents waiting to happen.

    It's funny that today, all you have to do to make something unpopular is put Atomic in front of it, and all you have to do to make it popular is to put nano in front of it.
    Had they called this a nanoscaleparticleenergyconverter instead people would be flying off their chairs screaming "What a wonder!"
  • Re:Fuel (Score:4, Informative)

    by AtomicJake ( 795218 ) on Thursday December 20, 2007 @09:44AM (#21763712)

    TFA says it'll use lithium-6

    But Lithium-6 [] is stable, i.e. not radioactive. It can be used to produce Tritium [] by neutron activation, which in turn is used in thermonuclear weapons. But for Neutron activation [] you need another radioactive source. So, what's this source? Or is Toshiba using a totally different process?

    I doubt that these are properties of an export hit ...

  • Where we live ... (Score:2, Informative)

    by Anonymous Coward on Thursday December 20, 2007 @09:45AM (#21763726)
    >I live in an area where that is not near any water, has only intermittent sun and wind so another power source is necessary. One question: why? Everyone will need to think harder about the cost effectiveness of their living situation in the future. Google is thinking about this now, and setting up data centers near large sources of hydro power. I suppose you could grow trees and burn them, like my parents did in the 1970s when heating oil got expensive. Not environmentally friendly because you still get CO2 out. There are very efficient stoves that burn corn products now.
  • Re:Where we live ... (Score:3, Informative)

    by pipatron ( 966506 ) <> on Thursday December 20, 2007 @10:01AM (#21763856) Homepage

    I suppose you could grow trees and burn them, like my parents did in the 1970s when heating oil got expensive. Not environmentally friendly because you still get CO2 out.

    Guess where that CO2 came from. That's right: The trees got it from the air. Burning trees won't add anything to the air that wasn't already there in the first place. Burning coal and oil adds CO2 from millions of years ago, which is the real problem.

  • Re:Cannot Find (Score:2, Informative)

    by Guinness2702 ( 840158 ) on Thursday December 20, 2007 @10:08AM (#21763922)
    I think it might be real. See this search [] for more matches.

    And if that doesn't convince you, then the first match, this reliable source [], might.
  • Let me guess (Score:2, Informative)

    by Anonymous Coward on Thursday December 20, 2007 @10:13AM (#21763962)
    you work for the white house? According to wiki, it is STILL going in. [] "greenies" have had nothing to do with it. In fact, according to the wiki, just this year, the town confirmed it.

    My suggestion is that you go back to preaching about the WMD that Iran/Iraq/NK has. It is idiots like you that cause more issues than the "greenies". They voice concerns. You and your neo-cons voice lies.
  • by savuporo ( 658486 ) on Thursday December 20, 2007 @10:13AM (#21763966) []

    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 []

    Wonder why it never went anywhere ?
  • Re:Fuel (Score:5, Informative)

    by Anonymous Coward on Thursday December 20, 2007 @10:24AM (#21764096)
    6Li is a neutron absorber. Its advantage is that it produces essentially no gamma radiation, as the dominant channel is 6Li(n,T). Tritium is produced, but in a reactor like this it will presumably be all inside the seals. The alternative shielding material, 10B, produces gammas as well, requiring lead shielding.

    The lithium is a regulator and shielding component of the reactor, not a fuel. It'll be fuelled by moderately enriched uranium, much like a Slowpoke.

    Interesting fact: 40% of electricity generated in Canada is lost to transmission lines and conversions. One of the big gains from tech like this would be the reduction in transmission losses.
  • []

    The 4S uses neutron reflector [] 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" [], 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 [] 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 [], 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 [] - and heated sodium explodes just as easily [] 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?
  • More info (Score:5, Informative)

    by Xelios ( 822510 ) on Thursday December 20, 2007 @10:47AM (#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 [] 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 [] 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.
  • Different reactor (Score:3, Informative)

    by Xelios ( 822510 ) on Thursday December 20, 2007 @11:04AM (#21764668)
    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 [].
  • by Quintin Stone ( 87952 ) on Thursday December 20, 2007 @11:19AM (#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 SixFactor ( 1052912 ) on Thursday December 20, 2007 @12:28PM (#21765772) Journal

    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 [] 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.
  • by caffiend666 ( 598633 ) on Thursday December 20, 2007 @02:04PM (#21767050) Homepage

    Because one of the test teams died miserable deaths: [] . 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.

  • Re:Where we live ... (Score:2, Informative)

    by celtic_hackr ( 579828 ) on Thursday December 20, 2007 @02:11PM (#21767160) Journal
    Sorry, you've got it backwards.
    Trees release Oxygen into the atmosphere, and breathe in CO2.
    But burning them will release more CO2 into the air than they took in.
    This is why it's sooooo important to pay attention in chemistry class.

    So the only way to reduce CO2 is stop making it in
    energy sources, or reduce the "Surplus Population"!
    Reducing the Tree population by burning it, only makes the CO2 situation worse!

    If you kill a tree and burn it you:
    1) release the CO2 it has absorbed from the air and from the chemical reactions taking place as a result of burning the complex organic compounds that comprise wood,
    2) remove a source of a CO2 cleanser.

    Hence you release more CO than was in the air before the tree existed, and you wind up with more CO2 on a daily basis because it is no longer removing CO2 from the air. But this is /. and science is forbidden here.
  • by jhantin ( 252660 ) on Thursday December 20, 2007 @02:28PM (#21767370)
    Pu-238 is much too unstable to use in a thermonuclear device; too much of it will cause a premature partial detonation. However, it makes a dandy small scale energy source. Plutonium batteries were manufactured in the 1970s for devices such as pacemakers that needed a long term service-free power supply. Also, strontium and cesium based radiothermal generators were used in the USSR to power such things as remote lighthouses that would've been hideously inconvenient to supply fuel to in the winter.

    As for U-235, I think one of the most inventive uses I've seen is powering a nuclear saltwater steam rocket engine for interplanetary use. Just watch where you point it, the exhaust is really nasty.

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

    by dgatwood ( 11270 ) on Thursday December 20, 2007 @03:08PM (#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:Submarines (Score:3, Informative)

    by hcdejong ( 561314 ) <hobbes AT xmsnet DOT nl> on Thursday December 20, 2007 @03:10PM (#21768228)
    The nuclear plant in a sub takes up something like 1/3 of the internal volume. this page [] 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, power output 60 MWe) was about 2x1 m. The rest of the space is taken up by the cooling circuits, turbines etc.

    A naval plant also uses highly enriched fuel so the reactor can be smaller than commercial ones.

    I wouldn't consider these to be 'very small'.

To avoid criticism, do nothing, say nothing, be nothing. -- Elbert Hubbard