Backyard Nukes?

By John Conway | November 12, 2008 5:56 pm

Miniature nuclear power generator.  Image courtesy Hyperion Power Generation, Inc.I am not sure if this is clean, or it’s green, but at least it doesn’t emit CO2.  The net is full of stories recently about new, miniature self-contain nuclear reactors which supply  25 megawatts of power, when and where you need it.  The technology was developed at Los Alamos National Lab, and is now apparently being commercialized via a company called Hyperion Power Generation, Inc

The miniature power plant  is truck-sized and buried underground for the five years it operates.  HPG says it has no internal moving parts, needs no maintenance, and emits no pollution (though I am guessing there amy be a few neutrons and gamma rays flying around, which is a good reason to bury it; HPG doesn’t talk about this).   After five years, you replace it, like a battery.   

It may be a while before one of these is literally in your back yard, since you probably don’t need 25 megawatts of power, and also because one of the units purportedly costs 25 million dollars.  But for, say, a university like mine which already has its own power substation, it might be quite feasible to install one of these babies underground, and enjoy much cheaper power, selling any excess back to the power company.

But all this kind of set off my inner skeptic…let’s do the math. Present commercial rates for power are about about 10 cents per kilowatt-hour. These mini-nukes last five years, putting out 25 MW. My trusty HP-15c tells me that this represents 219 million kilowatt-hours per year, or just over 2 cents per kilowatt hour!  That would be a nice savings. (Note – original post was in error here!)

Then, on the company’s own web site FAQ it ways that each module puts out 25 MW electric power, but 70 MW thermal!  Definitely don’t want that in my back yard – and so does one need a 70 MW cooling tower? Or use the waste heat somehow? This kind of ruins the nice picture of the thing sitting quietly underground while a couple strolls on the surface…70 megawatts is like 30 sticks of dynamite exploding per second.

In addition, of course, anti-nuclear activists will howl in protest: there are the obvious issues of nuclear waste storage (we won’t open Yucca Mountain until at least 2017), uranium mining, terrorism during transport, and more.  

But there may be plenty of applications where this would seem to be a great solution, like remote locations or already secure places with big power needs. In the long run we will need more nuclear power plants to offset carbon emissions.   Maybe this solution is better than giant multi-gigawatt installations?

CATEGORIZED UNDER: Environment, Technology
  • http://www.darcynorman.net D’Arcy Norman

    Where this stuff gets really interesting isn’t necessarily in replacing The Grid, but in making lots of power available to places far away from The Grid, for about the same cost. Remote islands. Research stations. Evil Lair Headquarters… I’d guess there are military applications, too. Airlift one into Kandahar, and plug it into the base grid. Done. Stable power.

  • Imam Yahya, Commander of the Faithful, etc

    “of course, anti-nuclear activists will howl”

    Good.

  • http://lablemminglounge.blogspot.com/ Lab Lemming

    “Airlift one into Kandahar”
    And hope they don’t shoot that plane down.

    Based on that picture, the shielding seems to be about an order of magnitude too thin.

    And John, the heat production is only a problem in nobody in your neighborhood takes a shower. Otherwise, the heat can be used for the European-style centralized hot water production.

    If these take off for powering mine sites, it will be interesting to see how Australia reacts. Especially if they allow off-shore competitors to cut costs.

  • No thanks

    A request for the graphic designers of this site … can you PLEASE put a left margin on the text? It’s really annoying to read otherwise!

  • R

    How did you get 9 cents per KW-hr?

  • http://Capitalistimperialistpig.blogspot.com capitalistimperialistpig

    Hmmm? 70 MW. How big a swwimming pool could I heat with that?

  • John

    R: I take 25 megawatts, which is 25,000 kilowatts, and multiply by the number of hours in five years,
    which is what the company says is the lifetime. That’s about 219,000,000 kilowatt-hours. Now, if the thing cost 25 million dollars to begin with, that’s 11.4 cents per kilowatt hour. So my trusty HP failed me and I will edit the post.

    Thanks for the cross check!

  • http://en.wikipedia.org/wiki/Stirling_engine IVAN3MAN

    Then, on the company’s own web site FAQ it ways that each module puts out 25 MW electric power, but 70 MW thermal! Definitely don’t want that in my back yard – and so does one need a 70 MW cooling tower? Or use the waste heat somehow? This kind of ruins the nice picture of the thing sitting quietly underground while a couple strolls on the surface…70 megawatts is like 30 sticks of dynamite exploding per second.

    Why not use Stirling Engines to make use of the waste heat? Click on my name for the link to the Wikipedia article.

    P.S. I am a first time reader of Cosmic Variance and a first time poster on it. I usually bother Dr. Phil Plait on his Bad Astronomy blog, so I thought that I should give him a break and check out this blog instead. Nice!

  • http://rightshift.info Traums

    Well, anything that decentralizes power production is welcome.
    The heat should be used to run a traditional heat-exchanger based steam-turbine plant.

  • anonymous

    John – they say

    Enough power for 5+ years | After 5 years, removed & refueled at original factory

    http://www.hyperionpowergeneration.com/about.html

    Which I take to mean the physical part – the reactor vessel, the cooling system and steam turbine – last a lot longer than five years, it’s just the fuel that’s spent. “5 years” is the period of time that it goes without refueling, not its productive lifetime.

  • Paul

    My maths might be wrong, or I’m misunderstanding something, but I can’t get the 291 million kw hour estimate for five years at 25 megawatts of electric power John has in his post. Multiplying 25 megawatts (25,000 kilowatts) by five years (approximately 43,830 hours), I get approx. 1095 million kilowatt hours. Multiplying 25,000 kilowatts by just one year (8765 hours), then I get the 219 million kilowatt hours figure in John’s post.

  • agm

    Two words as to why this might be interesting: Hurricane Ike.

    Power out for days to weeks, coming back up in stages. Backup generators everywhere for police/fire/EMS/hospitals. This could be useful for a city’s emergency management and recovery operations.

  • joe

    One word: Moonbase

  • SR

    I agree with Paul. Working it on Google calculator I get ~10^9 kw-hour, which works out to 2.5 cents an hour. Where do II fail?

  • http://st-lemur.livejournal.com Edmund Schluessel

    They’ve been talking about this for a few years in Galena, Alaska, just the kind of remote city you’d want it for.

    And yes, any reason why you couldn’t built the thing inside a Dewar flask and stick a Stirling engine on the top — especially in Alaska?

  • http://mirror2image.wordpress.com

    Isn’t 70 MW thermal output with 25 MW electrical telling that reactor heat exchange is not at maximum efficiency ? Usual nuclear reactor waste heat is like 2:1, here it is more like 3:1. Also conventional reactor use cooling tower to get rid of waste heat. Useful heat utilization for reactors is only in projects now. Here they kind of cheat, not including heat utilization into the product itself, leaving it for customer. Their lower efficiency also could be result of size and cost reduction. I suspect to really use this thing substantial infrastructure should be built.

  • http://mirror2image.wordpress.com Serge

    Ops, sorry made error in the header…

  • http://blogs.scienceforums.net/swansont/ Tom

    Paul and SR are right. The original calc divides only a year’s worth of energy into the cost of the plant, but the plant lasts 5 years. So the calculation is too large by a factor of 5.

    8760 hours x 25,000kW = 219,000,000 kWh. That’s only one year.

  • http://blogs.scienceforums.net/swansont/ Tom

    Oh, and you don’t need a 70 MW cooling tower (or whatever method dissipates the heat). You are converting 25MW of that to electrical energy, so there’s 45 MW left over.

  • http://bash.editia.info jgabios

    actually they will install some of these in romania where i live.
    a week ago there was some news that they will buy some small nuclear plants from these very guys you talk about here and power up a few neighbourhoods in bucharest.

  • mr paul

    when comparing the costs, don’t forget to include rising rates in your electric bill. Use error bars to handle the uncertainties of fuel supply, possibility of CO2 tax, the cost of the backup generator that you won’t need, etc. The benefits quickly start to reveal themselves. Of course, the cost of the reactor should include the cost of spent fuel storage. Let’s assume that a storage site can handle the waste from a million of these. Let’s assume that it only takes one FTE 24×7 to guard and manage the site, and it is a minimum wage job ($6.55/hr). Assume 1% average salary increase (we’ll ignore that it really happens in bursts). lets see – $6.55 x 24 x 365. Let’s use excel to amortize that over the storage time, roughly 10,000 years. Calculation: FV(1%,10000,6.55*24*365) = $93,860,579,790,607,300,000,000,000,000,000,000,000,000,000,000,000.00

  • Sili

    What Lab Lemming said about decentralised heating.

    How much does this baby weigh? Would it be feasable to use them in Antarctica?

  • mr paul

    oops. I forgot to divide that number by a million. So its only $9.3 x 10^43 per unit.

    This is one thing I don’t get about nuclear power. When the government computes the storage costs, they look at the costs over something like 50 or 100 years, and ignore the rest. My calclulation uses ridiculously low numbers for all the things we can understand, only to point out the incomprehensibility (even to physicists) of the storage costs. What are the real costs? I have no idea, and nobody else does either.

  • Jon

    If this thing can generate over 1000 million KWh in 5 years, as Paul said, than the cost of the electricity would be a little less than 2.5 cents ($0.025/KWh). Now I think this is absolutely amazing. It means that you are generating electricity at a quarter of the market price. I don’t know if the obligation on utilities to buy excess “home grown” electricity at commercial price stands for this kind of generation as it does for renewables, because if it does, than this would be the hack of an investment, you’d get 4 times the amount invested in 5 years. Obviously, that amount is in the form of multiples of 25M$, which might not fit very well in the average family budget.

  • Jon

    Notice that currently utilities are paying 0.1 cents ($0.001/KWh) for the storage of the waste, so the price of the electricity produced doesn’t change much because of this problem. That actually makes sense, since nuclear reactors with more than 1GW, which can provide electricity to about 1 million people, only produce a few cubic meters (less than 10) of waste per year. Think of a cubic meter as the volume of a small desk. I think that $0.001/KWh * 1GW * 1 year = 8.76M$ should be enough for taking care of such a small amount of material which, as far as I know, as never injured anybody in the entire world (I’m still talking about the waste generated by commercial power plants).

  • thomas

    UMass Amherst likes thermal power (i don’t know how much, but the buildings are piped together for steam). Probably, there are many other college campuses which might be interested. And cities. Unfortunately, not so much in the US (yet!).

  • mr paul

    The problem with the amount that the utilities pay is that the government charges them based on cost calculations for the 50 or 100 years. So the utility pays a one-time fee to dispose of the waste. The one-time fee covers the cost of handling the waste for 50-100 years. Who pays the cost for the handling after that? Our grandchildren. How big is the cost? Look at my calculation.

    The points are (1)any calculation you read about the costs of nuclear power are inherently dishonest. Nobody calculates the storage costs beyond 100 years. But they are there. (2) Our descendants are going to have to pay to secure and maintain the spent fuel from our energy consumption. They get no benefit from the waste, but they have to pay the costs of keeping it safe. Imagine if the pyramids could be used by terrorists or irradiate the surrounding area if we weren’t constantly guarding them and maintaining their condition, all because of choices the ancient Egyptians made. Would we be pissed at them?

  • thomas

    Many people have suggested in this thread that they use the waste heat to drive a Stirling engine.

    A heat engine needs a hot reservoir and a cold reservoir and is more efficient the further apart those temperatures are. Heat engines will always dump some heat into the cold reservoir instead of doing useful stuff with it- it is the nature of a heat engine to harness the tendency of things to come into thermal equilibrium (that’s the zeroth law of thermodynamics) to get some work done. A heat engine can’t just take thermal energy from a hot thing and convert it directly to work, that would violate the second law of thermodynamics: all those particles are running around with something on the order of kT kinetic energy in different directions, and you want them to go in the same direction to push something? Doesn’t happen, the vast majority of possible states of those particles have them swimming around not going anywhere in particular (look up the ergodic hypothesis).

    So no, they’re not going to be able to get much more energy by running a Stirling engine off the waste heat. But, that heat has to go *somewhere*, so maybe they could heat your shower water with it?

  • Reginald Selkirk

    They say its safe because it has no weapons-grade fuel. But they need to consider the possibility of use in a “dirty bomb.” That means security needs must be incorporated into the cost-benefit matrix.

  • Jon

    Assuming that a cubic meter of waste is the result of producing 0.1 GW of electricity for one year = 876MWh, we get 876000$ from the waste fee of $0.001 per nuclear KWh generated. Assuming the storage site can take one million cubic meters of waste, the total fund available for this site would be 876 billion dollars. I don’t know how much of this would be required to dig the hole or whatever it takes to build the repository, but with an interest rate of 1% above inflation per year on what’s left after the construction, let’s say 100 billion dollars, we would have every year a budget of 1 billion dollars to pay for the maintenance costs, which would last indefinitely. I honestly think it should be enough.

  • anonymous

    mr. paul:

    You seem to have a minor sign error in your exponential function. Deferred costs are less expensive than immediate costs, not more – the sign in the exponential is negative.

  • mr paul

    anonymous – we’re not talking about a deferred cost. We’re talking about ongoing operational costs for something that provides no value. Very different.

    As for the general statement that deferred costs being less expensive than immediate costs. This is only true when there is no impact from deferring the costs. How much money was saved by deferring the costs of maintenance on the I-35W bridge in Minneapolis? Do you defer your personal purchase costs by only paying the minimum amount on your credit card each month?

    No, the Future Value calculation is correct – except it is far too LOW due to the silly assumptions I made.

  • Count Iblis

    It should be possible to convert almost all of the energy from nuclear energy to electricity. The amount of energy that can be converted to useful work is given by the difference in Gibbs free energy of the fuel and the waste products. In case of nuclear fission the difference in Gibbs energy is practically the same as the released energy.

  • Mike Bevington

    Isn’t there always low-level contamination from any running nuclear reactor? I think the Berkeley campus TRIGA reactor required some significant cleanup after it was shut down. What remains after the reactor is removed?

  • Count Iblis

    Mr Paul, the long term cost of storage of nuclear waste is simply that some space will be occupied by nuclear waste, like the planned site at Yucca Mountain.

    If you generate electricity using a coal fired powerplant, you are not even storing the Co2! So, not only do you have waste, you are allowing that waste to cause damage. The CO2 waste problem is far harder to deal with properly than the nuclear waste problem because of the huge volume of Co2 you would have to store.

  • mr paul

    Count Ibliss – I completely agree with your statement about the CO2 problem. In my mind, they are both extremely hard problems to properly quantify. The sheer amount of CO2 , its dispersion, and the range of possible impacts all make it hard to know what the real costs are. With nuclear, you have a well defined set of issues to contend with, so it seems like the problems are more addressable. However, the time frames are so long that no one really can say any solution will work with sufficient certainty. In those time scales, once in a decade events are commonplace, once in century events are frequent, once in a millenium events will happen multiple times, etc. Don’t forget, we’re not really talking 10,0000 years. We’re talking tens of thousands of years.

    As for the cost simply being that space will be occupied. That simply isn’t so. There will need to be continual monitoring of the site, inspections and verifications that there are no surprises, fixes applied to surprises, and, most likely, 24×7 guarding. You can’t just seal it and walk away.

    Jon makes a good point about a fund being able to perform well enough that the interest can cover the costs, but the bottom line is there is no evidence that a fund can exist for anywhere near those timeframes. Do you really trust the government to let it sit and grow and only take out what is needed? And, from what I’ve read, the amount set aside is not enough to realistically cover the long term costs, because the calculations used to set the mil rate all assume it only needs to address 100 years.

    The Heritage Foundation has an interesting proposal for handling nuclear waste using the free market. (http://www.heritage.org/Research/EnergyandEnvironment/bg2149.cfm) Unfortunately, that is how we currently handle electronics recycling, and there is plenty of evidence that the results are riddled with problems. But they make a lot of good points about the economics of nuclear storage.

  • kletter

    Let’s see – this is a small-scale enriched uranium reactor, probably graphite moderated, that functions by fission of U235 in fuel that is enriched to ~3% or so, right? Just as in any ordinary reactor, there will be the formation of plutonium-239 via neutron capture from the non-enriched uranium, the U-238.

    So, one, if you don’t cool the thing, what’s to keep it from melting down and sending a plume of radioactive isotopes up the chimney? Second, how much spent fuel does it produce per year?

    The amount of stored plutonium in the U.S. is about 250 metric tons (2005). That’s enough for ~40,000 nuclear weapons. If one were to go and extract all the plutonium sitting in nuclear waste repositories across the U.S., you’d have another 500 tons of plutonium. Not only that, there are huge costs looming from decommissioning the first round of nuclear reactors built decades ago. These costs are not going to go away.

    In any case, small-scale portable nuclear is a terrible idea, mostly because of the security issue, but also because of the waste issue. Wind or solar power along with robust energy storage system is the way to go for any remote installation – that’s why satellites rely on solar power, and not on nuclear power packs. Not only that, wind and solar don’t require cooling fluids.

  • ioresult

    I thought of using the heat for heating by 24 feet swimming pool, but that baby is gonna evaporate it in 2.35 seconds flat!

  • Lawrence Crowell

    I am not so sure this is a good idea. I suspect that in a few decades we will see solar panels which one applies to surfaces like wallpaper. They may be composed graphene layers of great thinness in layers on some flexible substrate. All one needs to dois “cut and paste, plug and play.” I think I will hold out for that before signing on to this idea.

    The problem is that there is still the waste disposal issue, and these are essentially disposable reactors. Also one can’t just bury these things and expect all to work fine. Some array of sensors are needed to make sure materials are not being deformed or failing in some way. Even still one is putting it in the ground and hoping for the best. Also with hundreds or thousands of these around the world who is to absolutely ensure nefarious type will not get the fissile material?

    This sounds like the latest nuclear “great idea,” in line with the promise 15 years ago or so of pebble bed reactors.

    Lawrence B. Crowell

  • Mark Greenman

    Hyperion sent me a white paper which explains a bit more the principles.
    It is moderated by hydrogen gas diffusion between the reactor core and a surrounding bed of pebble depleted U. The hotter the fuel bed gets, the more hydrogen is driven off, which paradoxically reduces the effective neutron-induced fission rate. This is an older concept, proven about 40 years ago by a reactor design group lead by Freeman Dyson. That said, initiating the thing to critical fission production, and stopping it with the rods inserted into the pile (not shown in the picture) is a control problem. It looks to me like not something that happens without direct access to the reactor, meaning they won’t be burying the first prototypes, if ever. The heat exchanger rods will contiain either gas, or molten sodium, producing a control and containment issue unto themselves. The thing appears a lot more complicated than the company -Hype-rion promotes publically.

  • Ben M

    About waste heat: if you’re using these things to replace (e.g.) University-scale cogen plants, then there are plenty of uses for the low-grade waste heat … i.e. the heat you can pull out of the exhaust stream without killing the efficiency of your turbine. (This is possible because you’re using a real-world turbine, not a textbook cartoon of one, for which the efficiency is constrained by many effects (friction, conduction, compression ratios) in addition to the underlying thermodynamics. These real turbines can’t get their exhaust gases down to ambient temperature without losing efficiency elsewhere. So don’t think that “running the generator efficiently” and “having waste heat for other uses” are mutually exclusive. They’re not.

    There are lots of uses for waste heat. In the winter it plugs into your heating system. In the summer, it regenerates the absorber in an absorbtion-cycle refrigerator, which provides chilled water for building A/C and for lab chillers.

  • http://blogs.scienceforums.net/swansont/ Tom

    The hotter the fuel bed gets, the more hydrogen is driven off, which paradoxically reduces the effective neutron-induced fission rate

    Nothing paradoxical about it. Higher temperature means lower density, which reduces the moderating efficiency. More neutrons leak out before they become thermal, and thermal neutrons have a much higher chance of inducing fission.

    But I read that this is based on the TRIGA design, which is described as a swimming pool reactor, which I assumed meant a boiling water reactor.

  • QWerner

    So or so nuclear energie is on of the worst thing the humans did. For the most people its difficult to imagine how mutch wast alread is produced. And even more difficult to have an idee how toxic the wast is. A few micrograms inhaled plutonium will cause cancer (long discussion, rats, distribution…). Lets assume 10 micrograms. Than we can kill with one kg Plutonium 100.000.000 peoples. Used fuel element consist of a huge zoo of isotopes.
    This is accently the most dirty thing you can imagine.

    If some one clamed this as clean and he is in charge and has the knowledge he is (almost) mass murder. Because he is taking to people they do not know and have to trust.

    Anyway, this brilliant idee of miniature power plant is criminal. They claimed to sell 4000 un 10 years around the world and have already oders from Tschechien and dispute with the Cayman-Ilands, Panama and Bahamas. I am shure they will come all back.

    And have they run one of them 5 years?

    Neutron radiation modify the structure of stell.

    They use UH3 which recersible decompose around 500°C into U and hydrogen. Because hydrogen is the moderator the reaction is self regulating. But this means they have to seal the reactor. So a huge increase of temperature will produce a nuge preasure.

    How they deal with the fission product Xe135?
    Due to Xe135 has a high probability to trapp a neutron the will arise Xe136 wich is stable.
    Hence Xe135 makes around 6% of the fission product (normal reactor) and Xe135 has a half-value period around 9 h they will be around 1%-3% Xe136 as a stable fission product.
    Its a gas.
    So the pressure increase with livetime.
    This means that decomposition enthalphie of UH3 invrease with livetime. So the reactor will be hoter if he gets older.

    We dont talk about the issue that they want to use Kalium in the colding system which is a bomb if it get contact with water.

    so there are some thought from me.

    Better we take sunenergy. And silicon as energy storage.

    best

  • Lawrence Crowell

    I agree about 90% with QWerner. I am not dogmatic about “no nukes,” and I suspect that nuclear energy may play some future role. I do hope that this can be minimized however. Nuclear energy has a poison pill element to it that we have never been able to eliminate.

    You do make a point in that it would be almost a religious faith that one could bury these and expect all to run without a hitch. Neutron damage or pressure build up, even if previously accounted for, could have unexpected consequences. If one of these fails and spews out it would result in a mini-Chernobyl incident.

    Lawrence B. Crowell

  • http://science1.wordpress.com/ Zeynel

    QWerner Says:

    “nuclear energie is on of the worst thing the humans did.”

    Isn’t this an unjustified generalization? It was not humanity who created nuclear energy and nuclear weapons but professional physicists.

  • QWerner

    Yeah, of caurse I am not docmatic;)
    I select sometime strong words for a strong issuse.
    By today’s view we need the nuclear energy. But it is important to buildup as fast as possible sunenergy ect. and than to plan the rest of the nuclear energy.
    And to change the hole energy production needs alot time.
    And slowly the nuclear energy companies excange the technologies.
    There will be no finacional lost fore the companies.

    I am shure that the physicist in los alamos are realy good.

    Fantastic scientist.
    Onla wrong direction.

    Also nuclear scintigraphy: Te99
    liver cancer; Selective Internal Radiation Therapy (SIRT) : Y90

    best

  • QWerner

    Jes, it was professional physicists. But they all are affected by the society.

    Oppenheimer and Einstein were in america because of the nazies . 6. Januar 1939 Lise Meitner, Otto Hahn and Fritz Straßmann discover the nuclear fission.
    In this momant Einstein and Oppenheimer knowed there will be the bomb.
    And Einstein knowed they all personally and what they can.

    So Los Allamos.

    I thing that is a huge impact of society in sciene.

    I know good scientist, with a socialisation which would totally colaps if they would realise its not save.

    “nuclear energie is on of the worst thing the humans did.”

  • QWerner

    @Lawrence Crowell II

    I am shure that they calculated exactlly.
    Xe136 is well included. Its basic.
    And I belive that this miniature power plant will be save in respect of there technic and construction, but not save in respect of the society.

    Its only the wrong direction.
    And the biggist lost is the power of the scientist.

    imagine they all would develop totaly cool hightech.

    A electric car has a higher momentum as a otto-motor.
    Tesla Roadster 0–60 mph (0–97 km/h) in 3.9 seconds
    speed is electronically limited to 125 mph
    you would never change back.

    The idee of decentralisation is good for wind-energy:)—-
    but realy definitly not for nuclear energy.
    (man, and they claimed it as a advantage…..)

  • John

    I am so sorry! My original calculation was off by a factor of five. I went ahead and modified the post, for posterity, though it’s rather late now… Thanks to the readers who pointed out my obvious error.

  • Jon

    This is best analysis that I’ve found on the web so far about nuclear waste:

    http://www.phyast.pitt.edu/~blc/book/chapter11.html

    This is the 11th chapter of a book entitled “THE NUCLEAR ENERGY OPTION” which was written by Bernard Cohen who is Professor Emeritus of Physics at the University of Pittsburgh. You can check his Wikipedia Page here:

    http://en.wikipedia.org/wiki/Bernard_Cohen

    Take a look at these quotes from the beginning of Chapter 11:

    “As an initial perspective, it is interesting to compare nuclear waste with the analogous waste from a single large coal-burning power plant… For example, if all the air pollution emitted from a coal plant in one day were inhaled by people, 15 million people could die from it (3), which is 10 times the number that could be killed by ingesting or inhaling the waste produced in one day by a nuclear plant.(4)”

    “For nuclear waste, a simple, quick, and easy disposal method would be to convert the waste into a glass — a technology that is well in hand — and simply drop it into the ocean at random locations(5). No one can claim that we don’t know how to do that! With this disposal, the waste produced by one power plant in one year would eventually cause an average total of 0.6 fatalities, spread out over many millions of years, by contaminating seafood. Incidentally, this disposal technique would do no harm to ocean ecology. In fact, if all the world’s electricity were produced by nuclear power and all the waste generated for the next hundred years were dumped in the ocean, the radiation dose to sea animals would never be increased by as much as 1% above its present level from natural radioactivity.”

    Check this particular section which, to some extent, answers the concerns mr Paul as been talking about:

    SHOULD WE ADD UP EFFECTS OVER MILLIONS OF YEARS?

    I haven’t read the entire book yet, but this chapter and the one about comparing risks from various sources seems very interesting. The book seems a bit technical and is full of references to calculations in the appendix, but I strongly recommend everyone to take a good look at this.

  • Jon

    This is best analysis that I’ve found on the web so far about nuclear waste:

    http://www.phyast.pitt.edu/~blc/book/chapter11.html

    This is the 11th chapter of a book entitled “THE NUCLEAR ENERGY OPTION” which was written by Bernard Cohen who is Professor Emeritus of Physics at the University of Pittsburgh. You can check his Wikipedia Page here:

    http://en.wikipedia.org/wiki/Bernard_Cohen

    Take a look at these quotes from the beginning of Chapter 11:

    “As an initial perspective, it is interesting to compare nuclear waste with the analogous waste from a single large coal-burning power plant… For example, if all the air pollution emitted from a coal plant in one day were inhaled by people, 15 million people could die from it (3), which is 10 times the number that could be killed by ingesting or inhaling the waste produced in one day by a nuclear plant.(4)”

  • Jon

    “For nuclear waste, a simple, quick, and easy disposal method would be to convert the waste into a glass — a technology that is well in hand — and simply drop it into the ocean at random locations(5). No one can claim that we don’t know how to do that! With this disposal, the waste produced by one power plant in one year would eventually cause an average total of 0.6 fatalities, spread out over many millions of years, by contaminating seafood. Incidentally, this disposal technique would do no harm to ocean ecology. In fact, if all the world’s electricity were produced by nuclear power and all the waste generated for the next hundred years were dumped in the ocean, the radiation dose to sea animals would never be increased by as much as 1% above its present level from natural radioactivity.”

    Check this particular section which, to some extent, answers the concerns mr Paul as been talking about:

    SHOULD WE ADD UP EFFECTS OVER MILLIONS OF YEARS?

    I haven’t read the entire book yet, but this chapter and the one about comparing risks from various sources seems very interesting. The book seems a bit technical and is full of references to calculations in the appendix, but I strongly recommend everyone to take a good look at this.

  • spyder

    The WAAGNFNP has long been an advocate for the policy of nukes for everyone. We can imagine an era when neighbors bond with neighbors in their gated communities freely exchanging recipes for enriching their stock of uranium and for proper handling of plutonium. We look forward to the day when burbclaves build tactical speedbump nukes to insure the safety and security of their own. This is a giant blessing for the entire human species. Hell, if Jon is even thinking reasonably, all those glass bricks of concentrated nuclear waste would be perfect for building new houses and shops for the locals. I mean, if it is okay for the fish, it is fine for people, right???

  • Realistic

    mr paul wrote on Nov 13 7:19am,
    “FV(1%,10000,6.55*24*365) = $93,860,579,790,607,300,000,000,000,000,000,000,000,000,000,000,000.00″

    Mr Paul, you estimated the storage cost of spent fuel by compounding the guardian’s minimum wage over 10,000 years. In doing so, you ignored a gigantic factor.

    Namely, you assume that the 25 MW of energy generated by the mini-nuke is worthless. The economic benefit of all that energy is difficult to estimate but should be several orders of magnitude greater than your guardian’s salary of $57,378 per year. This economic activity, like all economic activity, should be compounded too, and should by itself greatly overwhelm your FV calculation above.

  • Brody Facoum

    How many Communists are in the State Department kW⋅h are in a HPG 25 kW(E) reactor?

    … and this is why we normalize to SI units.

    (Okay, admittedly we can expect other normalizations on a blog dominated by qc-gr topics, but I’m almost tempted to argue that geometrized or Planck units are less confusing to deal with than W⋅h).

    Now it’s my turn to make errors!

    How many joules do we get from 25 megawatts over 5a? Let’s assume the usual mean calendar year, since there are so many years to choose from.

    1 a = 3.156e07 s [from NIST]
    5 a = 1.578e08 s
    2.5e07 W * 1.578e08s = 3.945e15 J

    Normalizing bills, which are almost always for energy rather than power:
    1 kW⋅h = 3600 J
    10 cents / kW&sdoth; = 2.778e-8 USD / J

    3.945e15 J @ 2.778e-8 USD / J = 1.096e8 USD ($110 million)

    So, $25 million vs $110 million for almost 4 PJ of energy @ 25 MW of electrical power.

    This ignores additional costs not included in the $25 million price, which might include things like insurance.

    This also ignores additonal savings from the additional thermal energy doing work that might otherwise be done by electric, gas or oil boilers.

    Finally, a question: what’s the power decay curves (electrical and thermal) of these small plants? Apart from the issue of isotope half-life, these piles are unmanaged, sot therefore they can develop unfavourable arrangements with respect to neutron economy, right? Five years is an unusually long duty cycle for a working nuclear pile.

    Maybe this solution is better than giant multi-gigawatt installations ?

    That’s a hard question to answer! Transmission losses from the giant installations are a large factor, but so are economies of scale — much hotter rectors lead to much more efficient electrical power generation per unit of fuel; alternatively bigger piles gain economies of scale with respect to on-line refuelling and other reactor pile geometry management (e.g. CANFLEX) which leads to less downtime and greater fuel efficiencies. These are unlikely attributes for a “no maintenance” small reactor.

    In either case, the really rare resource, engineering and operational expertise, remains highly centralized, which is why the idea of large numbers of “non-field-repairable units” is tenable.

    The bigger practical risk to the users of these reactors, I think, is not one of these reactors failing dangerously, but rather failing safely as designed, but taking a long time to be replaced because of production and delivery backlogs.

    However, if there are a mix of large and small power generators, and a grid that can cope with dynamically distributing energy from supply to demand, the overall energy economy is more resilient in the face of plant outages (including planned maintenance and construction delays). Whether such a grid is realistic is an open question. At present, “selling excess power back to the grid” does not work in the way you probably think.

  • Brody Facoum

    Oh fantastic. Rule 1 of the Internet is that when trying to correct someone’s spelling, grammar, math or other mistakes, you will introduce your own. At least I knew that going in…

    Me:

    1 kW⋅h = 3600 J

    Obviously wrong!

    1 kW⋅h = 3.6e06 J (3600 kJ)

    10 cents / kW&sdoth; = 2.778e-8 USD / J
    3.945e15 J @ 2.778e-8 USD / J = 1.096e8 USD ($110 million)

    These I got right, althought it should be “kW⋅h” rather than “kW&sdoth;”. Character-order typo. No preview. Blinding glare of background whiteness. Those are my only excuses.

    [Aside: on OS X you can do a sort of preview by command-a (to highlight everything in your edit box) command-c (to copy) then at the shell prompt (everyone runs Terminal, right? :-) ) run "/usr/bin/pbpaste > /tmp/a.html" then "/usr/bin/open /tmp/a.html" which should cause your default browser to show you a formatted version so you can at least check your links and see dangling markup tags that cause half your comment to be italicized...]

  • Damien R. S.

    mr paul, you compound the minimum wage of a guard over 10,000 years, to get some huge number. But who’s paying that? Not us now, but society over time — the economy of which is also compounding at 1% if the minimum wage is. A minimum wage guard is still a minimum wage guard.

    Never mind that compounding as naively as you did implies the guard 10,000 years from now is receiving about $6e43 per hour.

  • Pingback: Mini nuke plants « sand grain

  • Sean Maurice Hunt

    Disposable Nukes…what a great idea! Everyone knows that radiation is good for you whether it be from Mobile Phones, Blackberries beaming into your brain or dental x-rays pointed at your head cat scans or whatever its proven that radiation in all forms must be good for us otherwise why would these Corporations keep creating these items.

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