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Fission in a Box
Jim Howard writes: "The The World and I magazine has an article suggesting the following interesting possibility: 'Advances in South Africa and the Netherlands suggest that small-scale fission machines could become safe, reliable, and inexpensive sources of electricity and heat for ships, factories, and perhaps single-family homes.' Well worth a look, if only for the review of nuclear power basics." Don't hold your breath, because technical obstacles aren't the main ones. But it's a nice overview of the science behind small reactors.
I believe your statements are both off topic and irrelivant to the article.
Firstly, it is South Africa doing the immediate development and deployment, not the US. The US, its whitehouse, and the US congress, have no say over the deployment of the technology. The article indicates that deployment in 2005 is planned.
I hope so, the technology in the article seems very promising. With deployment in 2005 approved (according to the article), it should be an interesting development to watch in 2005.
I really doubt that the South African government has any interest in drilling off the coast of Florida. I doubt that the white house will have any say over the regulation of nuclear energy in a foreign country.
You are off topic buddy.
Warning: Anonymous Coward is a KNOWN TROLL!
See all his posts in this thread!
He is not on-Topic, ever!!
Aaaaaa! I'm sure that in 1985 you can find plutonium in every corner drugstore!
You're wrong. Using less than 1% of the uranium we mine like we do now, you're probably right.
If we use breeders and reprocessing though we can use all the uranium, and all the Thorium as well. That gives us enough for many hundreds of times as long. A conservative estimate would be something on the order of 1,000 - 10,000 years. If we don't have useful fusion by that time we deserve to be in the dark.
Tyler Ward
tjw19@columbia.edu
not only that, but coal burning plants in the USA release more radioactive particles into the atmosphere every year than all of the US nuclear power plants use as fuel combined.
if that horribly poorly constructed sentence made any sense.
A big problem with the design of the Chernobyl reactor was that when the temperature rises, the speed of the reaction increases, causing a run-away effect. Not good.
Also, they were explictly overriding safety controls to perform a test. It failed, obviously.
The plant at Three-Mile Island had an intrinsically safer design where if the core temperature rises, the reaction is automatically shut down.
The people in the area surrounding TMI actually received less radiation from that accident than you'll receive simply taking a flight from LA to NYC.
Geomthermal energy is indeed used in a number of places; Rotorua, New Zealand for one. The problem that popped up in Rotorua is that people end up depleting the source (underground steam pockets) faster than they were replenised. Oops.
More to the point, dams have a fairly significant ecological impact.
And the best part... the patents will have expired.
Unfortunatly, we will still be seeing primarily 70's sitcom reruns which will still be covered by copyright. To prevent the theft of that valuable intellectual property, pressing record on a VCR will carry the penelty of death by slow torture (perhaps the forced viewing of the same 70's sitcoms till you crack and hang yourself).
Meanwhile the makers and owners of the tidal generation equipment will be secretly lobbying congress to require that the new Mr. Fusion units be legally restricted from use for any purpose except for the creation of simulated tidal movement of the oceans. They will also be lobbying for that use to be publically funded.
In other news, Microsoft-ATT-AOL-Time-Warner-Cisco-Verison-Lucent -Daimler-Chrysler-UnitedStates Inc. will announce that in just 40 more years they fully expect to reach 20% national coverage with their new and improved TCP/IP over PPP over Ethernet Ovet ATM over FDDI over DSL over Avian Carrier service with a maximum bandwidth of 1.2 Mbps (ANd a typical figure of a whopping 76.2Kbps). Meanwhile, the tiny republic of Togo will be completing their rollout of 100Gbit fiber to the home (replacing the 10Gbit fiber). The average time between ordering and going online will be a mere 4 years (unless it takes longer).
Meanwhile, just about the time that the last U.S. citizen manages to replace the last remaining organic part in his body with a long life man-made part, the president will at last sign a universal health care bill into law. It will cost the taxpayers an extra 10% a year in taxes, and be paid directly to a consortium of HMOs. The new universal insurance will not cover man-made parts.
The Aetna-Prudential-Met-BlueCross news network will hail the new law as a victory for the american people. Lobbiests will then turn to the critical issue of universal life insurance. They will have plenty of time to work on it since all 'human' systems will be triply redundant with an MTBF or 2000 years. That law will pass only 100 years after the last recorded death of a 'hum,an being'.
That should about cover it.
or burying them a few miles deep under the ocean floor, with the holes plugged with clay (which water doesn't flow through readily).
This is the one we should be doing. Deep sea ocean drilling is well understood. The plan I saw in a Scientific American a while back was that you drill a hole about 3-4km into the ocean floor. Then every 10m or so drop a barrel of waste down the hole, and cover it with the clay/sediment you previously drilled out up to about 1km. Assuming 50 gallon drums with the density of water that would be 300 drums of 400lbs each or 120,000lbs of waste. The additional point here is that you do this near a subduction zone, so in a few thousand years the waste ends up in the mantle.
Seems like a more permanent solution than indefinite land based storage.
I disagree i would feel much safer with them burried in holes kilometers under the ocean floor and covered in ocean sediment. Even when the barrels release their contents they will only soak not much more than 10m in a sphere into the surrounding clay. If you don't drop anything shallower than 1000m there is pretty much no chance of contamination. And, evetually it all end up in the mantle. I read an article about this proposal in Scientific American a few years ago. It was a very well thought out plan that was summarily dismissed in favor of the site in Nevada.
Here is the question I have never seen anyone answer...
A fission bomb such as the ones dropped in World War II have a yield of a few 10s of kilotons of TNT with a few 10s of kilograms of fuel. Or, about 1 kilogram of fuel per kiloton of yield. Or, about 500,000lbs of chemical reactant per kilogram of nuclear reactant. Which leads to my quetion which no anti-nuclear environmentalist has ever answered.
Given a choice would you rather deal with a thousand pounds of nuclear waste, or 5,000,000,000lbs of carbon dioxide, carbon monoxide, nitrous oxides, sulfur dioxide, etc. etc. from fossil fuel plants?
Dastardly
When you're talking about a star, there ain't much difference.
he he he... Folks on Long Island are still paying for Shoreham.. (Oh wait, didn't the rest of us in NY state bail them out? :(((((( )
Your Working Boy,
- Otis (GAIM: OtisWild)
Opps. My bad. I should have looked at the map a bit more closely.
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Don't like it? Respond with words, not karma.
Waste disposal becomes simpler when you consider that the radioactivity of the waste drops below the natural ore after 5000 years, not the "millions" usually claimed as the time needed for them to decay. Most of the radioactivity is lost in less time than that.
Yeah, I'm sure Clinton did too, and I have no doubt that he is intelligent. In fact, in terms of intellectual ability and rhetorical abilities, I suspect Clinton is more capable than Bush (though I would not same the same for Gore), but I believe Bush makes up for it in spades in other areas. i.e., better organized, solid people skills, common sense, focus, no hubris, strong people under him, less Party baggage (as in overall better objectives insofar as the Presidency goes), ethics, loyalty, etc. I think the Bush will ultimately win the public over, no matter how much the Press wants to tar and feather him.
Not necessarily. Here in Illinois, ComEd generates 75% of it's power from nuclear fission, without any environmental problems so far. As a result, my electricity bill is always lower than my phone bill or internet access charges. And this includes using electrical heat over the winter. No soaring natural gas bills here!
Not that nuclear energy is always right, but if handled correctly it is a great alternative. With existing safety standards enforced properly, it is probably more environmentally friendly than burning coal.
Your right to not believe: Americans United for Separation of Church and
Well, it's obviously ridiculous that someone could cause a nuclear explosion with one of these. But I certainly wouldn't want someone to play with one of these and end up breaking it, and dump it somewhere where the fuel or waste would end up coming out of my kitchen faucet.
This isn't really a new problem, though. There's already all kinds of horribly toxic substances available to people who are watched far less closely than nuclear reactor owners.
It really comes down to the more general problem that evil or stupid people have the capacity to ruin innocent people's days, and technological progress only makes it easier and easier for it to happen. Since our society has basically given up on the idea of holding people accountable for their actions, we rely almost exclusively on a preventive approach, which means limiting everyone's power, regardless of however responsible they may be. Thus we get gun control, drug war, etc. Because of that, I don't think there's any way one of these reactors would be allowed in USA.
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As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
Maybe this can be a Good Thing for Third World countries. We still have the problem of pollution by nuclear waste, however.
-- Cheers!
The only erroneous assumption is that there will be less people out of work. In an evolving society the workforce is constantly transferred to different areas. If this didn't happen we would be stuck in a medival scenario where a very large percentage of the population worked with food production.
Technology that makes it possible to decrease the number of people working in some area is always welcome since those people can instead be transferred to new areas where they are needed.
There are of course short term disadvantages such as layoffs but hopefully a working society should handle these problems. (I leave it up to others to debate how good/bad our society is though)
You're right, by diversifying the energy supply all renewable sources can be used. I just finished a PhD showing that just due to the effect of distributing wind turbines all over Europe, wind energy can easily cover 20% of the demand even within the hour-by-hour constraints of the current power plant mix. This is due to the (simple) fact that somewhere the wind always blows. Within Europe, the distance you need for a good smoothing is about 1500 km, much more doesn't make sense.
Solar power could give another 20-30 %, and the hydropower potential is not yet completely used up: on one end of the spectrum, there is a lot to be gained by small hydro (tens or hundreds of kW, with a potential of some single digit percentage), and on the other end there is the Grand Inga project in the Congo, with a potential of 45 GW. That is roughly as much as the installed capacity of the rest of Africa (bar South Africa) combined; or half as much as the installed capacity in Germany.
Hurricane Application Group, Dept of Meteorology Control, Ministry of Proactive Defense
The 300MW Thorium-cooled High Temperature Reactor in Hamm-Uentrop went live in 1983, but had mediocre success. I don't remember why, but do a Google search on THTR-300, and you'll find even stuff in English.
Hurricane Application Group, Dept of Meteorology Control, Ministry of Proactive Defense
Sorry, thorium is the fissionable material, not the coolant - that was helium...
Hurricane Application Group, Dept of Meteorology Control, Ministry of Proactive Defense
Moving at a foot a year, itll be 20 feet underground in maybe 30-40 years, and thats plenty of shielding.
By my calculations, moving at a foot a year, it'll be 30-40 feet underground in 30-40 years.
Whew, math is hard. I need a beer.
. . .for my Delorean Time Machine ??? I can only afford Wal-Mart fuel !!!!
What about geothermal?
Always seemed pretty sensible to me...
anything wrong with it? Eh?
Just my luck... I've been reading up on the pebble bed reactor recently, and the one day when I could have scored a "5 - informative" with this link, http://www.uilondon.org/sym/1999/kemm.htm, I'm in the lab instead of the office. Great page - discusses the science, the politics, the economics of coal vs. pebble bed modular reactor (PBMR).
Briefly, SA has lots of coal and uranium, but neither is near where the power demands are. You can't realistically stretch power lines across those open distances without unacceptable losses, so the power plant needs to be local. A localized coal-fired plant would mean endless trainloads of coal to be shipped in, thousands of tons of soot and CO2 in the air. The PBMR can store a year's supply of fuel on site, has lots of passive safety features, and fuel elements that are really difficult to reprocess into anything especially dangerous. It's quiet, no smokestack, the turbines can be water- or air-cooled (flexible siting), and run by technicians without MS's in nuclear physics.
Like I said, just my luck to post this after the discussion has already died down. No karma boost.
The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
That vegetation wouldn't is created by the dams. In running water you don't get the same massive growth you get in stagnant water. Besides, the problem is much worse than that. Dams destroy ecosystems associated with the river that they are on.
The server seems slashdotted, so I couldn't read the article.
But it sounds a bit good to be true. We can always hope...
Close, but not quite.
You are correct that the nuclear reaction stops when the moderator is lost, but fission is not the only source of heat in a reactor.
A signifigant fraction of the heat generated is from the radioactive decay of fission products. For many reactor designs, this decay heat is enough to raise the fuel temperatures to damaging levels if it is not removed.
Decay heat is what caused half of the Three Mile Island core to end up as a puddle on the bottom of the pressure vessel.
All this depends on the materials used in the construction of the fuel elements and the size of the core. A smaller core will have larger heat losses with normal cooling removed. I believe that there are suitable materials now that can withstand high enough temperatures to make decay heat removal not an concern, but This is not the case for most reactors currently in service.
It sounds like you are describing a negative temperature coefficient of reactivity ("negative void coefficient" if you are a civilian). In a water-moderated reactor, an increase in temperature will reduce moderator density therefore cause a tendency for power to decrease. This provides for negative feedback and causes reactor power to change to match the heat removed from the system without operator intervention. This does not prevent an over power condition - it just means that the reactor is inherently stable.
[The Chernobyl fallout pretty much trashed cities 200 miles away.]
And if Chernobyl had a containment dome like all western reactors, it wouldn't have contaminated anything but the immediate area. Still bad, but nowhere near a bad. If you have ever seen pictures of Chernobyl before the accident it looks like a large office building, not any sort of nuclear power plant. The force of the steam explosion would not have been sufficent to break throught a containment dome built to western standards.
Also, as bad as the fallout was, it clearly didn't completely ruin even the immediate area around Chernobyl since the other nuclear reactors as the site continued operation until just a couple of years ago.
The paper attacks the economics of the PMBR. Worse, it does it the way a five-year-old does magic tricks (See the quarter? Now close your eyes.... it's GONE!). The assumptions change with the point being made. Item. Look at the 'biomass' bar on the CO2 graph, page 13 - it is -zero-. How are you going to -move- that much biomass? With non-polluting oxen?
There is a long, obligatory 'let's scare the proles' section about how dangerous nuclear power is, but there isn't anything in there that admits the PBMRs are -not susceptible- to the accidents they discuss.
Dreadful reference; this is a bunch of smear tactics, very slightly removed from outright fraud. The only value in the paper is it's the last one I need from Earthlife Africa.
You're on the right track, however. One proposal has been to set those waste containers in a subduction fault, where a tectonic plate is being pulled down...and eventually will become molten rock in the mantle. The core of the Earth is believed to be molten due to radioactive heat, so a little more radioactivity in the area won't matter.
Do you have any idea how much plutonium is in the concrete of your Hoover Dam?
Now, onward to the discussion of accuracy of various suppliers of "journalism"...
I'd rather be worried, because:
- disposing it in a safe manner costs n
- disposing it in a not-so-safe manner probably costs n - x
- disposing it in an unsafe (and unlawful) manner surely costs n / x.
Of course, I'm talking about short-term costs. Everyday you can hear of toxic dump being stored improperly or in abusive dumps, and now tell me how we can ensure the same won't happen with nuclear disposal, expecially when the number of subjects to be controlled is going up by an order or two of magnitude?I know the alternatives (coal) sucks. But without a serious answer to the problem above (greed and short-sighted behaviour), this is going to suck even more.
Hmm. But I'd like a bit of a slowdown. A 25 hours per day period would match my natural day/night cycle much better.
Ummm, last I checked, it wasn't just economically impossible, it's technologically impossible. We can't yet sustain a fusion reaction.
No, we can sustain a fusion reaction. It just takes twice as much power to sustain then it generates. Fusion is here, unfortunatly it effciency is less than zero. Kind of sad isn't.
Also I don't believe that solar power relies on heat conversion. It takes excited photons, for something like the sun and slams them into a material with easily slammable electrons to create a voltage. And then uses the voltage to create power. They work in really, really deep space where it is really, really, really cold (if there is enough entergetic photons around that is.). They are also known to work in less cold places like Antartica.
That's "proven reserves", which are 30-40 years today, were 30-40 years ... uh, 30-40 years ago, and will probably still be 30-40 years "proven reserves" 30-40 years from now as more is discovered.
Beyond that, if we just reprocessed the spent fuel rods, we'd have about 100 years proven reserves. Breeders take that to several hundred years.
And beyond that, you can breed fissionable U233 from thorium. According to the CRC Handbook, thorium is "about as common as lead", and "there is probably more energy available from thorium in the earth's crust than from uranium and all fossil fuels combined."
And beyond that... The Japanese have demonstrated a technique using ion exchange resins to extract uranium from seawater at a cost of about $200/pound in 1970-something dollars, which was when I read about it. Grossly too expensive now, but if we really needed the uranium...
main problem with tokamak reactors is that lithium aint cheap -- its as expensive as hell if large quantities are required and a fairly rare element. eve if someone managed to mass produce working reactors (which they havent been able to get working properly in a lab yet) they wouldnt be cheap enough for mass consumption (cant have one in your basement or car for example).
ive read that paper -- its a load of bullshit. while the statistics it gives in economic terms are impressive .. they are irrelevant because it omits one key fact -- what is the main technical problem with the PBMR design which renders it unsafe ? if it cant answer that question IMHO the paper is irrelevant. south african import/export and monetary economics do not count to debunk a perfectly valid technical design.
How do you know that nuclear power is efficient?
Efficiency of a machine is directly dependent on the temperature diffrence that drives it. In case of nuclear we can produce and utilize with wery few components, a very high temperature indeed. Hence efficiency.
The thing that you have neglected to mention is that, right now, there is no long-term solution to the nuclear waste problem
There is: Build reactors that can be driven by this waste. Until you reach stable iron you can gain energy this way. The implementation is merely a research project.
Some of the isotopes have half lifes on the order of 10^6 years...
Bombard them with neutrons to reduce this (and release energy at the same time).
About $1000 a kilowatt:
9 43 58,00.html
http://www.localbusiness.com/Story/0,1118,LAX_5
Great for distributed uses and "peak shaving". Not so good for overall bulk producing. The price is correct, though. Auxillary costs, such as land, pipelines, and pollution credits are not accounted for. However, don't just discount facts because you are'nt willing to do the research.
The abbreviated Laws of Thermodynamics:
1)You can't win.
2)You can't break even.
"We all do no end of feeling, and we mistake it for thinking." -Mark Twain
Nope, nuclear power isn't very efficient. You're producing huge amounts of heat just to boil water, just like coal power plants.
Converting heat energy to mechanical energy is really hard to do efficiently, and it doesn't matter if the heat comes from oil, coal, the sun...
Fusion power is not economical yet either, although there are projects in the works.
Ummm, last I checked, it wasn't just economically impossible, it's technologically impossible. We can't yet sustain a fusion reaction.
At least you got the safety stuff right...
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All glory to the hypno-toad!
Also, there are social implications - unemployment and the death of an industry.
The industry ? Well it will have to give up on polluting the planet with all this nice C02 the US electic industry seems to love so much. As for the workers, well, someone will have to make and operate those fusion reactor... last time I checked, they don't use people anymore to grow cotton in Alabama... an industry always has to die or change somehow, and it's not always so bad for its workers.
Um, I have a degree in Nuclear Physics, and you, sir, are full of shit.
There are definite dangers with nuclear power, and, seeing as how I've done nothing with physics since graduating college (I'm a computer programmer), I won't propose that I know whether the dangers outweigh the advantages.
However, I know this much: nuclear reactors may melt down, but without some _extremely_ unlikely events, a nuclear explosion cannot occur.
It doesn't take any knowledge of nuclear physics to realize this. If you could take power plant grade uranium (as opposed to weapons grade) and build a fission bomb, wouldn't the terrorists be doing it right and left? It takes high grade uranium or plutonium and a demolitions expert to compress it to critical density to make a nuclear bomb.
As I don't have a degree in Nuclear Physics, i'd like to get your opinion on Liquid Metal Fast Breeders, in particular, the IFR design at Argonne West. It seems to me (a layman) that this solves most all of the problems with current reactors. Your thoughts?
Well, one way to harvest electricity more directly would be to use the heated gas from the reactor to power an MHD (magnetohydrodynamic) generator.
However, to do this with any efficency the operating temperature of the reactor would have to be raised slightly to plasma temperatures. This could present engineering challenges.
Now you have me wondering if anyone has ever tried building a reactor where the fuel was gaseous, say U235Hexafluoride at a proper compression and reactor vessel configuration...
Unfortunately I suspect this would have some of the same drawbacks as using hydrofluric acid as the heated fluid in an ordinary reactor, plus a few.
you mean it's not already?
You're right ! Killing an industry for the sake of progress is totally unacceptable !
We should reinstate the hundred thousand of telephone operators and dismantles the evil computers that have replaced them ! Why destroy an industry for the sake of cheaper, higher quality product ?
We should abolish potato peeling machines at once, providing jobs to thousands of people that'll be able to lead a fulfilling life as potato peelers !
A nuclear reactor can not explode. A modern nuclear reactor can't even melt down.
The main obstacle to getting nuclear power (the safest, cleanest form of power) used everywhere is the panic people go into when they hear the word 'nuclear'.
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Win dain a lotica, en vai tu ri silota
Looks like some moderator overrotated their scroll wheel. Interesting? Funny, perhaps, but not interesting.
just my blog and pix
The size of the actual fission device might fit on a table, but what about the 10+ metres of concrete and lead shielding that would be needed to placate people with fear of radiation?
Actually the fission-fusion-fission bombs as they are also called do have strategic value. The nuclear weapons FAQ for example, mentions that probably most of the strategic warheads are of this type today. The reason is simply to have the smallest package, the smaller the warhead is the smaller your entire ICBM can be (=cheaper). Since the warhead needs a heat shield for reentry anyway, why not make the shield of a material that can increase the yield? Besides, U238 is abundant and dirt cheap...
This is just what we need to do. Lets start giving out little pieces of hot uranium to people. If we give 'em MTBE, it ends up in our drinking water. Give 'em Lead Paint, it ends up in our lungs. Give 'em DDT, it ends up in our tumors. Give 'em non-weapons grade uranium and it ends up where?
-Moondog
"Mr. Atom is your friend."
Atomic-powered cars would run for ten years without ever needing refueling. Miniature home-sized atomic generators would generate copious amounts of electricity and hot water for kids who like to take long baths. Atomic rockets would propel mankind through the solar system and towards the stars before the oh-so-futuristic date of 1980 ...
Personal atomic generation was eventually discovered to be a Bad Idea, and dismissed. You have to consider that the same sort of people who would be using these generators would be the geniuses who light up a cigarette and then go off to fill their car's gas tank with said cigarette dangling from their lower lip.
That having been said, I believe that we can use nuclear energy wisely to provide power. As this article mentions, there are much safer, proven designs that could conceivably be deployed with far less risk compared to America's dangerous aging water-cooled beasts.
Our problem is disposal.
We need a disposal answer before we do anything else with nuclear power. Many short-term storage facilities at our current reactors exceed their intended maximum capacities by several times. We have all of our long-term storage proposals mired in red tape. I suspect our nuclear plants are more dangerous to the public from what is stored at them than from their hot, operating cores.
Knowing this, we can all beat our chests and act outraged, but that does not solve the problem. :)
Gas-cooled reactors are a great proven technology, but at least here in the United States before we break ground on one more reactor we have to do something about the current amount of high-level waste scattered all around the country.
One quick point to the people who say nuclear waste should not be transported ... The fuel pellets that produce the nuclear reaction that generates the waste have to get to the reactors somehow. They do not teleport. They arrive by rail, road, or ship. Nuclear material is transported all the time. Do you remember the last time N.E.S.T. was called out to decontaminate a neighborhood, a city, or a tract of farmland? If you do your memory is better than mine.
We need to put this stuff somewhere, long term, below ground. We have locations. Keeping it aboveground solves nothing, and actually creates more of a danger.
Get off my virtual lawn, you damned virtual kids!
Unlimited growth == Cancer.
Whoops, my bad memory strikes again. Slowpoke is not a water-boiler. Here's some info on Slowpoke.
Getting tired of Slashdot... moving to Usenet comp.misc for a while.
When Fort St. Vrain was built, I don't think it was called a GTHMR... just HTGR for High Temperature Gas-cooled Reactor. Same thing for Peach Bottom 1. Neither of these plants used a direct-cycle gas turbine for energy conversion; there was a steam generator with core-coolant helium on one side, and water/steam on the other to drive a normal steam turbine. They had terrible seal-leakage problems at St. Vrain with their main helium circulators; monatomic helium is incredibly tiny, and very difficult to keep from leaking everywhere. The core internals design for these older HTGRs and the PBMR featured in the article is very different also. The HTGR fuel used similar fuel-spheres, but they were packed into large, hexagonal graphite blocks with integral coolant channels. The blocks interlocked to form the core. Nice idea, but I imagine refueling was a bitch. The fuel cycle for these plants was supposed to be that of a thermal breeder, with a uranium-thorium fuel cycle. The breeding ratio was not terribly high, but I believe it was shown to be greater than unity (i.e., more fissile uranium created than consumed). I don't know too much about the history of Peach Bottom 1, but there is a lot of good information about Fort St. Vrain at the following location: Fort St. Vrain History.
Getting tired of Slashdot... moving to Usenet comp.misc for a while.
Wasn't slowpoke (and most early research reactors) water boilers with an aqueous solution of uranyl-sulfate or something? No fuel rods, I think... just a big liquid solution with fuel mixed in.
Getting tired of Slashdot... moving to Usenet comp.misc for a while.
MTC (moderator temperature coefficient) in modern LWRs (light-water reactors) is usually negative at beginning of core life (a core is usually designed to last 18 to 24 months). This is because LWRs are designed to be under-moderated, i.e. less than optimum moderation, so that increases in temperature (and decrease in density) of the moderator cause the fission reaction to slow down. However, it is possible to have positive MTC near middle to end of core life due to conversion of U-238 to Pu-239 in the core (2/3 of power generated from a fuel element is by plutonium at end of fuel element life), and the core, on average, may be slightly over-moderated because of this.
Another situation is where you have a graphite moderator and light water coolant, as in the RBMK reactor (Chernobyl type). In this case, there are situations wherein heat-up of the coolant (making it less dense) increases the moderating effectiveness of the graphite... i.e., flashing coolant leading to bad things happening. This would actually be termed a positive void-coefficient of reactivity, as opposed to a temperature coefficient... but whatever.
The situation described above for Chernobyl is not an issue for a gas-cooled reactor using helium coolant, like the HTGR or the PBMR. Helium gas has no nuclear cross-section to speak of, so does not affect the moderation of neutrons at any temperature, high or low. That's a desirable feature.
Getting tired of Slashdot... moving to Usenet comp.misc for a while.
Sorry... that was long. Short answer... the probability of fission in fuel material is extremely dependent on both fuel and moderator temperatures. Guaranteeing negative temperature coefficient of reactivity over all core conditions is a good thing, although a positive coefficient can be mitigated through good design.
Getting tired of Slashdot... moving to Usenet comp.misc for a while.
There are t-shirts. You would have to visit the controlled facility in San Diego to get one. Visits are by invitation, only. I don't have the authority to escort visitors to that area of the campus. Sorry. (but you could see the basement IT facility. Wow!)
"Computers are useless. They can only give you answers."
"Computers are useless. They can only give you answers."
-- Pablo Picasso
Well, if you have ever participated in a large engineering project, you know that many subcontractors and partners are involved. A sub designed and manufactured the seals for FSV, but they represented the best technology available at the time. Unfortunately, they just weren't up to the task. This is not to excuse anyone. GA was prime and had ultimate responsibility. It was the first and last HTGR reactor built.
Seal technology has come a long way since then and GA is confident that the current design, quite different from FSV, will function correctly.
GA is a highly diversified technology involved in many different areas. Take a look at http://www.ga.com for a brief outline.
I can understand your ridicule. Your accomplishments must make GA's pale by comparison. I'm impressed by your detailed critique and rebuttal of GA's performance at FSV. But then, I'm easily impressed.
"Computers are useless. They can only give you answers."
"Computers are useless. They can only give you answers."
-- Pablo Picasso
This reactor type was invented by the company for whom I work, General Atomics. The site is here.
One of the GTMHR-type reactors was built at Fort Saint Vrain, Colorado, but was beset with seal problems. In the twenty years since, these problems have been overcome with the result that GTMHR is ready for prime time. The best part of the design is negative temperature coefficient. This means that they cannot run away. If they get hot, they shut down.
GA is also one of the foremost Fusion research sites extant.
"Computers are useless. They can only give you answers."
"Computers are useless. They can only give you answers."
-- Pablo Picasso
i hate to be a dick, but after a whole post railing some guy for getting fission/fusion mixed up, you then say we dropped fission bombs in WWI rather than WWII...
I am completely aware of this, take the statement in context with the rest of the post. Yes its funny, but its also a statemtnt against the type of arguments junk scientists tend to use.
A Beowolf cluster of these?
;-)
:-)
Somebody had to say it.
~Religion is O.K., as long as it gets you laid.
Fascinating. Thanks for the correction.
So what you're saying is, most of the energy produced by a fusion reaction go into the neutrons? I thought it was mostly gamma rays.
"Remember Nuclear power in the 1950's? Remember how it would provide electricity so cheap as to be free? How it would be completely safe? The reality has turned out to be somewhat different, has it not?"
:) Sorry, I couldn't resist.
The problem is not with nuclear power - it is with people. Nuclear power is a very useful tool, and it can be used to provide electricity so cheap as to be free. It still can be everything they promised, including safe if we can find a way to make electricity that isn't useful as a weapon. IEC fusion shows some promise in this area.
Remember, fission doesn't kill people, people kill people.
"Also, there are social implications - unemployment and the death of an industry. Do we really want to cause the death of an industry for the sake of cheap electricity?"
Sure we do. Why not. I'd like to see the art, music, and movies industries replaced, as well as big oil, big software, and big medicine. I'd like to see them replaced by something that frees people instead of binding them.
As for unemployment, it is very low in the US right now - so low that industries are having amazing difficulty recruiting and hanging on to employees. A touch of unemployment is healthy for the industries you seem to like so much. There is a balance to be had there. Low unemployment can trigger inflation, due to companies having to give their employees all sorts of incentives and then having to raise prices for the consumer. The employees in high-demand industries will not suffer, but employees in low-demand industries will because cost of living will rise but their paychecks won't. This could artificially widen the income gap between rich and poor.
"The millions of people who work in electricity plants, where nuclear reactors are used responsibly by the government, will beg to differ on that one."
Ummm... used responsibly by the government? There's been lots of nuclear accidents caused by governments besides just the famous ones. There have also been deliberate misuses of nuclear power by governments. Hiroshima and Nagasaki spring to mind. You seem to put undue trust in government.
As for millions of people who work in electricity plants, their skills will be useful elsewhere. Trained engineers can find jobs, if they don't mind a little retraining. Plus, I don't think there's really millions of them.
Any good docter would love to become obsolete. Why should electrical engineers be any different? I have mixed feelings about genetic algorithms and AI eventually replacing me as a programmer, but I'd like to see it happen.
"So, from a social and practical perspective I must be sceptical."
So should we all. However, you seem more cynical than skeptical.
"We must not embrace new technologies solely because they are new, but rather because they improve our quality of life. I don't think fission reactors fulfil that requirement."
I agree with your first sentence, but I think fission reactors could fulfill that requirement. I guess we'll just agree to disagree, then.
I love your post, but I have a few questions. For example, I'd rather see chain-reacting radioactives being used to make electricity than sitting in missile silos. For that matter, why can't we just dump the radioactives down a subduction fault? They're heavy, so won't they sink into the mantle quite nicely?
Yes, I'm aware that we can't simply dilute stuff like Strontium 90 into seawater because it gets concentrated with calcium into the animals higher on the food chain.
Would it be possible to make a mostly clean H-bomb by removing the depleted uranium? Just a thought.
Ouch. I am disappointed because I still had hopes for H-bomb powered Orion ships. I guess there really is no such thing as a mostly clean nuclear explosion. Even N-bombs aren't, because they'll make anything near them get radioactive.
Well, there's always the Beanstalk. I just wish they'd hurry up and find a way to make structures that light and strong. Why did buckytubes have to turn out to be so slippery?
/me pouts
Okay, an expert, finally. :) Why can't we just seal the radioactive waste in small, strong containers, and dump it in a subduction fault? Please excuse me if it's a dumb question, I'm just a guy who doesn't know any better. :)
Fuel cells? Where are you going to get the hydrogen? Fuel cells don't generate any new power at all. Electricity + water -> hydrogen + oxygen -> electricity + water is a lossy process.
You still need somewhere to get the original electricity.
"It seems to me that a LOT of energy would be lost in the transfer from heat to mechanical to electrical energy."
I agree. One more efficient way to get power out of radiation, if you happen to have a very predictable alpha emitter, is to surround the alpha emitter with a metal shell charged with just less voltage than the alpha particles have. The current flows in the opposite direction as the voltage wants it to, so you get electrical power. Rather like a capacitor that charges itself up over time.
Since the alpha particles have lost most of their momentum by the time they hit the metal shell, there is not much heat produced. Instead, there is quite a bit of electrical power. However, this requires that the alpha particles have a very predictable energy - that doesn't happen often.
Some IEC fusion reactors use a similar model, but they don't break even yet. They are very good neutron sources, though.
"However, uranium and plutonium aren't exactly compressible, so we're stuck with needing a good bit of the stuff."
:)
Oh, that's no problem, just surround the core with a bunch of fission bombs and set them all off at once to make the core reach critical mass without haveing to use much uranium or plutonium.
Oh, wait, what am I forgetting...
I think he was making a joke. I laughed, anyway. Maybe it was serious, though.
I heard something about solar panels producing less energy over their lifetime than the energy it takes to make them. Of course, maybe that was in Seattle or something.
Can you point me to some numbers that refute this idea?
Energy to make vs. energy made by it over a typical lifetime of a solar panel,
Price of a solar panel vs. price of electricity saved by using it,
that kind of thing?
In a word, no.
For an A-bomb, you need very purified u-235 or plutonium, because those are the only fissionables that will go critical. Secondly, you need a lot of this very pure stuff. A critical mass of it, to be exact.
Simple imaginary scenario. Generating electricity causes soot which causes cancer. When you pay for the electricity at cost, someone else's health subsidizes your extra-large refrigerator.
The plant where I work, a boiling water reactor, makes 1 GigaWatt carbon and soot free.
Now back to Joe San Diego. He's got no idea what you are talking about because you make no sense. He hears you blithering on about costs, but all he sees is a decline in his standard of living. I think he's going to get tired of you retoric like this:
To me it means first that the cost of every product should reflect not only how much money it took the producer to produce it, but also the cost of cleaning up the mess that third parties are left with as a result of both its consumption and its production. Second, green means that we should not party at the expense of our grandchildren. Taken together, what I want to say simply is that green means fair. But then again, I am a green-red colorblind.
Dude, that's so queer and jargon heavy it would even make Stalin cringe. The costs of production are always passed on as long as they are mandated by law. Disposal costs are also passed on, so long as the law requires the disposal in question, and it generally does. The regulated utilities are garanteed a certian percentage profit, all costs are passed on to Joe San Diego. We are all paying for these things, I'm afraid of what you might want to charge for.
You do not have a political future. You missunderstand what the people want because you think you know better than they do. This would be OK if you displayed any thechnical epertise, but you don't. Your arrogance has made you blind and incomprhensible.
Friends don't help friends install M$ junk.
Yes, but normally any vegetation that dies is replaced by new vegetation. If there is a dam, however, there is no new vegetation.
So, what are they going to call this...Mr Fission? I guess this is the precursor to the much more reliable and popular Mr Fusion...
You're using her as bait, Master!
Forgive me if I misconstrued your statement, but Three Mile Island is by Harrisburg, PA in Southern PA (the area I live in). Manhattan is roughly 150 miles away (not large on a Global scale, but somewhere like Philadelphia would have been a greater concern)
The press is not tar and feathering Bush. He has gotten a free ride, considering his past, and his Reaganesque hiding from press conferences where he does not come off very informed. Clinton was racked by 24/7 MonicaStain-NBC deathwatches, Faux News/RNC rumor planting, yadda yadda. The amazing thing is, they couldn't find a thing on a man who came up through Arkansas politics, even though billionaries funded investigations and the press wanted him dead. You have to be pretty clean to run that guantlet.
People skills? You mean he can charm his way past answering questions? Better organized? You mean other people are running the presidency? Focus? on what? No hubris? You mean he isn't a know-it-all (intelligent)? LESS PARTY BAGGAGE: ARE YOU INSANE? I guess his objectives are yours then. Ethics? The funeral industry scandal in Texas, his failed companies, cocaine use tho he denies fed aid to students convicted of even pot, dirty tricks against McCain, and the unbelievable dirty tricks campaign waged in Florida to get himself elected? Using his own rules for manual recounts, he lost. Even if he had won, the torturing of law by Saunders and the Supremes will always tar him with stealing the presidency. Loyalty? To whom??
In the future, everything will be in a box.
You have to get the Uranium from somewhere, generally it's mined out of the ground.
Most people freak at the thought of meltdowns and at the radioactive waste produced. We're already used to accepting the smog produced by Coal & oil plants, but radioactive disasters seem so utterly scary to the States, possibly as a result of years of Global Thermo Nuclear War fear?
-f
-f
www.blackant.net
Don't forget the A-Plane!
I have an old copy of an article about it, one of these days I'll dig it out of the basement and post it.
Oracle and unix guy.
In the early sixties there was a reactor accident where the reactor went a bit hot, blowing the steam boiler into the roof, smushing the poor workers who happened to be standing on top of the boiler. It was not considered a nuclear accident, of course.
So now we will have a flooding basement full of hot billiard balls cracking open as the water hits them...
Oracle and unix guy.
Nor, for that matter, will it tend to hang around for long, helium having the nice property that it tends to go straight up pretty quickly.
Is this so? I would think it disperses quickly, but only goes straight up if contained in a manner that allows density differences with air to manifest themselves. Dispersal might take thousands of years to leave the atmosphere... right?
Oracle and unix guy.
I agree.
Oracle and unix guy.
Wait a minute... exploding billiard balls?
Oracle and unix guy.
I live somewhat under 50 miles from a nuclear powerplant. That plant is on the seashore, approximately 2 miles from an active offshore earthquake fault. Anyone who buys a house near the plant receives a booklet about what to do in the case of release of radioactives. There is a near zone and far zone from the plant, which determines which booklet one gets.
The plant is near a Marine bombing test range.
Heat pollution is readily visible in the ocean as one drives by.
Terrorists could easily bring down the power lines from the freeway.
But yes, it's better than coal.
I know there is a fault there because I couldn't get earthquake insurance when I bought my house in 1986, because it had just had an earthquake. Yet, SCE claims there is no seismic activity in the area. RIIIIIIIIIIIIIIIIIGHT!
Oracle and unix guy.
Fission, the splitting of the atom into smaller atoms, is what powers all those nuclear bombs that are sitting in Russian, Chinese, American, etc. silos, waiting to destroy us all.
Actually, many of those are H-Bombs. Even worse, we don't know if or how many of them are FFF bombs - Fission-Fusion-Fision. FFF bombs are made to be particularly nasty. The first fission sets off the fusion reaction, which blows fissioning pieces all over the place. Dirty, dirty.
Oracle and unix guy.
Some smoke detectors (ionization detectors) have Americium 241 (Am-241) in them, a radioactive material with a half-life of 458 years. The amount is only 1 to 5 microcuries, but apparently enough to cause cancer if disassembled....
It actually will tend to rise very rapidly- much better than other typical gasses. For evidence that gasses don't need to be contained in order to rise, think about thermal plumes of various sorts; they rise and cause convection currents even though their difference in density compared to their surroundings is only a few percent. Helium is only about 1/7 the density of air, so it's going to go upward most satisfactorally. Bear in mind also that when escaping from a reactor it's also going to be thermally hot, which will help quite a bit.
Another critical advantage is that the helium itself won't become radioactive- it's a terrible neutron absorber- so even if it did get into the surrounding community it wouldn't contaminate it directly. And, of course, it won't get chemically added to the bodies of the locals the way some radioactive can.
There's no point in questioning authority if you aren't going to listen to the answers.
Nor, for that matter, will it tend to hang around for long, helium having the nice property that it tends to go straight up pretty quickly.
That said, the article does say that they don't forsee this kind of technology getting into homes anytime soon. Their suggestion was that the most likely use for it in anything like home use was as a power source for remote areas, when it would be an essentially sealed system without user servicable parts. There's already too much investment in power distribution infrastructure for it to be really sensible to try to put a nuclear generator in every basement. You might as well have them located somewhat centrally where they can be run by trained professionals and distribute their power through an already built and amortized power grid.
There's no point in questioning authority if you aren't going to listen to the answers.
The difference is that if the boiler explodes it will just kill people in that house, if the reactor explodes it could kill people (or make them sick) outside of that home. I would rather not place a nuclear reactor into my neighbors care that could kill me considering I wouldn't even trust most of them to drive my car.
Really? The administration will take an unpopular stance that they intend to step down from later, to distract from their real goals? Sounds uncharacteristically subtle to me.
I'm under the impression that the US government keeps track of all nuclear fuel. I know I've seen reports that Iraq has x-kilograms of fuel which they obtained from y and z.
If nuclear power plants became small, it would become much harder to track it all. That might imply that it would become much easier for Joe Terrorist to build an atomic bomb. Is that so?
?p?I know he pushes for unpopular things all the time. Sometimes he has to back down, sometimes he doesn't. But all those unpopular things (including drilling for oil in Alaska and the 1.6T tax cut) are things that he actually wants. Reducing CO2 emissions seems like something he wouldn't want, since it conflicts with a vibrant oil industry, which he clearly does want. ?p?Has Bush pushed for anything that was both unpopular and which he didn't want?
I've always wondered what is stopping us from building a scaled-down version of a nuclear bomb. Why make it so big it'll clear the tri-state area? Can't we make one small enough that it'll only destroy a city or two? It would still be a measure to strive to avoid, but it'd be better than current nuclear bombs.
--
atomic bomb! Could you take one of these little reactors slap a detonator to it and make a A-bomb!?
If so I'm moving.
Fission power is what fuels the hydrogen bomb
:)
Yes, you are technically correct, but H-bombs use the energy from a "dirty" fission reaction to provide enough boost to fuse hydrogen (the "clean" part of the explosion). That is the only purpose. It is the only way to get enough power quickly enough (in a self-contained device) to fuse hydrogen. It's not as if the fact that a fission reaction is used to induce hydrogen fusion makes fission inherently bad.
However, I agree with the assertion that fission power is dangerous. It has been dangerous since its inception and it's doubtful that anything will ever change that. The byproducts it creates are not a problem if handled properly by a large reactor, but the average citizen should never have to come near nuclear waste.
Ummmm, much of this planets core is radioactive; why not place the radioactive waste into a subsuming tectonic plate, and let the planet recycle it naturally?
Can You Say Linux? I Knew That You Could.
I remember reading an old Popular Science article about a nuclear battery technology that was intended for use in day to day electronics. It was an alpha emitter chemically bonded to a polymer along with a light emiting phosphor. The end result was a a translucent plastic that glowed. Because the radioactive eliment was part of the polymer, it was safe, even if the battery was shattered. The glowing plastic was thinly sliced, and sandwiched with solar cells. Many layers were stacked. The result was a battery that generated power for about 20 years. Coupled with a lithium battery for peak demand (which was constantly recharged by the nuclear battery), it was a perfect power supply for portable electronics. Does anyone know what happen to this thing?
Can You Say Linux? I Knew That You Could.
Ohhhh.... I didn't realize you had such a reliable source. The arrangement you describe would be IMPOSSIBLE to detonate. There have only been a couple uranium bombs ever produced, and they were nearly 100% enriched U-235. YOU CANNOT MAKE A BOMB WITH U-238 IN ANY WAY!!! It wouldn't detonate. The "depleated" uranium would only absorb a few neutrons and increase the fallout. It would TAKE AWAY from the yield. Yes, flame.
Wrong. Some of you are SO naive. Yes, U-238 is quite common, but U-235 is NOT. Furthermore, you MUST separate the U-235 from the U-238, which was EXTREMELY DIFFICULT! Do you even understand the difference?
And what are you calling "fast-fissile material"? Uranium does not fission from fast neutrons, but from thermal (slow) neutrons.
If the US did not want someone to release scientific material, do you really think that they would sue them? In matters of national security, the people would be arrested or worse...
When you are citing "proof" of your arguments, you should not use biased sources, or if you do, you should include a source from each side of the argument. The American Federation of American (Atomic) Scientists is a non-profit organization devoted to ENDING the arms race and is AGAINST nuclear weapons. The following paragraph is from their mission page. Bold face emphasis mine.
"FAS was founded as the Federation of Atomic Scientists in 1945 by members of the Manhattan Project who produced the first atomic bomb, to address the implications and dangers of the nuclear age. FAS is the oldest organization dedicated to ending the worldwide arms race, achieving complete nuclear disarmament, and avoiding the use of nuclear weapons, and much of its work has been in nuclear arms control and disarmament."
Yes. H-bombs include more uranium to increase their yield, but it doesn't increase it much.
Most of the power in an H-bomb IS due to fusion. There are many things, all of which pretty much unkown to civilians, done to increase the yield while decreasing the package size. One must remember that there are just a handfull of nations that posses H-bomb (or A-bomb) technology, and the instructions and schematics available in print or on the internet are NOT valid, nor do they come from actual weapons designers. Most of these "designs" are purely speculation of what a bomb may look like from the minds of physicists. You can rest assured that the governments of the world would NOT allow real plans or schematics to become public knowledge. Remember that even China has trouble getting plans from the US's weapons labs (maybe not THAT much trouble, but they at least know where to look for valid designs.)
Furthermore, a deuterium-tritium reaction only produces ONE neutron per interaction. You MUST have more than one neutron per interaction to sustain a chain reaction. This is as true in weapons as it is in nuclear reactors. Most of the neutrons produced in an explosion will escape the weapon and not be absorbed or result in further fissioning, especially if the U-238 casing is beyond the neutron source. Although U-238 is fissionable, it has an extremely low cross-section for fission. Its cross-section for neutron absorption is much higher. The most likely reaction is simply neutron absorption, which creates plutonium. Fast breader reactors take advantage of this, and breed plutonium in this way.
It is naive of anyone to believe that nuclear weapons design is common knowledge, and that the only impediment for weapons manufacturing is materials production and handling. In the Manhattan Project days, it was VERY difficult to obtain large amount (mere pounds) of weapons grade U-235 and plutonium. Gasseous effusion is probably the WORST and most innefficient way to separate uranium, but it was the only possible way at the time. Now, ionizing laser techniques are thousands of times more efficient and less expensive. The main reason most nations cannot produce nuclear weapons (specifically hydrogen-based nuclear weapons) is because they don't know how to arrange the materials, and they do not have the resources necessary to research them. There is a reason that many of the planet's most powerful computers are used in weapons design.
I am constantly annoyed by the number of "experts" in nuclear technology that exist. Many of these people are convinced that all things nuclear are shrouded in secrecy and lies. Yes, when it comes to weapons design, there are MANY secrets and quite a few lies, and I AM GLAD that there are secrets and lies. Possessing nuclear weapons and the technology necessary to produce them requires a maturity that most countries in the world do not posses. It scares me to see places like India and Pakistan threatening to destroy each other with nuclear weapons, knowing that they actually may do it. The US and Russia almost started a few wars, but each side was responsible, even with high tensions in the war room. (Fidel Castro urged Russia to attack, and US generals urged the US to attack during the Cuban missile crisis)
When it comes to commercial nuclear power, there are no secrets in the reactor or other systems, no super-secret scandals to make the public "think" that it is safer than it "really" is. I am amazed at the number of people that believe that any nuclear power plant can produce a mushroom cloud or even explode like Chernobyl. Yes, there were MANY mistakes and accidents in the early days when the technologies were being developed, but by the '70s, it was pretty well ironed out. The accident at Three Mile Island DID produce a nuclear meltdown. This type of accident was actually not incorporated into the design bases of the plant. The only reason the accident happened in the first place was because the operators DISABLED all of the automatic safety systems. They made all of the wrong decisions (although it appeared that they were doing the right thing according to the instrumentation) The worst possible accident occurred, yet there was no detectable release of radation outside the plant's perimeter, and NO ONE was injured or even over-exposed. TMI was actually a GOOD thing for the nuclear industry. It made it MUCH safer, and the training that nuclear operators go through now is most likely the most intense and the best of any industry. An airline pilot goes to the simulator once or twice a year. A nuclear reactor operator spends half a year in the simulator each year. TMI didn't kill the nuclear industry. Super high interest rates, banning of reprocessing and transportation, and the high cost of plant construction coupled with the expansive changes in regulations and safety modifications stopped all power plant orders. The accident in Chernobyl was caused by defeating all of the safety systems and "simulating" a disaster. That was a very successful simulation if you asked me. Furthermore, the reactors at Chernobyl were very old, graphite moderated reactors with a positive void coefficient and vertually no containment. The graphite became too hot, exploded, and took all of the fuel with it. Since no reactors in the US use graphite and since we do all of our simulations in simulators, this type of accident is impossible in US reactors.
Another myth I would like to put to rest is "China Syndrome." This is just plain impossible. Suppose the molten fuel in TMI did happen to puddle in the bottom of the pressure vessel and melt through, it would fall to the containment floor. As it poured from the bottom of the vessel, it would spread out on the concrete floor and become a thin puddle. As it spread out just a little, it would no longer be in a critical configuration, and the reaction would stop. The molten fuel would likely remain molten for a day or two, but its temperature would not increase, rather decrease, and would not be even close to the temperatures required to ablate concrete. Furthermore, the containment spray system would be constantly removing the decay heat, most likey causing the molten metal to solidify. Any of the hydrogen formed by metal-water reactions would either be purged, recombined, or prevented by chemical TSP baskets.
I'll get off of my soapbox now. BTW, I AM a nuclear engineer.
Yes. What I was saying is that none of the current operating reactors in the US are graphite moderated. Many of the reactors in the UK are, but they are still fairly safe. Personally, I like the idea of a graphite moderated, high temperature gas-cooled reactor for its secondary side efficiency, plus the secondary is exactly the same as is used in fossil fuel plants. The biggest problem with a graphite moderated reactor is that you periodically must "anneal" the graphite, which -could- result in fires, but with CO2 or He as a coolant, it would not burn readily.
I'm sorry, but you are wrong. More than 90% of the energy released in a hydrogen bomb is due to fusion. The fusion reaction itself is initiated by an A-bomb, much in the same way that conventional explosives trigger A-bombs. H-bombs are much more destructive due to the temperatures produced by fusion. Fission bombs are limited because the fission core reaches a size where it is no longer possible to get to completely react before being blown apart. No, H-bombs are not clean; however, when comparing the fallout levels of a large A-bomb to those of a very small H-bomb, the H-bomb produces magnitudes less fallout.
We will have the Bruit Squad abuse the author with Wiffle ball bats, and you can ask Hemos for your cookie. Keep fightin' the good fight, AC.
--
In spite of the suggestions and all the tests that I have made, I have not cavato a spider from the hole.
Something interesting my senior year high school english teacher told me:
Modern TVs don't really turn completely off when you turn them "off", they go into a sort of standby mode. That's why it doesn't take a long time to warm up like old TVs did.
Now, if you look at how much power is consumed by the TVs in the US not really being off, and at how much power is generated by nuclear plants in the US, the numbers are very close. So, in a way, one could say that the editor was correct!
Someone "just tested" and the fucker blew up. Not because they couldn't afford build a safe plant ("Exxon", "sober sailors").
--
I typed "hydrogen," but I was really thinking "helium." H... He... what's the difference? A proton? :)
A proton, two neutrons and an electron (when comparing hydrogen-1 and helium-4).
The sun is hot (It is so hot that everything on it is a gas: iron, copper, aluminum, and many others.)
The sun is large (If the sun were hollow, a million Earths could fit inside. And yet, the sun is only a middle-sized star.)
But, at least
The sun is far away (About 93 million miles away, and that's why it looks so small.)
And even when it's out of sight
The sun shines night and day
Apologies (and thanks) to TMBG.
Bugrit! Millenium hand and shrimp!
The Davy Crockett was a wholly ridiculous weapon anyway. The thing could only get the warhead about a mile from the launch site (For the 120mm launcher, that is. The 155mm launcher could make about 2.5 miles). Actual use would have probably been well inside that range, due to accuracy concerns. Firing procedure would have been something like this:
1.) Aim weapon at target.
2.) Dig hole deep enough to hide in.
3.) Fire weapon.
4.) Jump in hole, pray to preferred deity.
Bugrit! Millenium hand and shrimp!
The lithium also serves as the coolant, similar to the water in a typical fission reactor. So the only thing that is subject to high levels of neutron activation is the innermost wall of the coolant system. You wouldn't want to spend much time near one, but I don't think it would produce any more free neutrons per kWh than a fission plant does (with equivalent shielding).
Bugrit! Millenium hand and shrimp!
wonder what the fertility rates will be like after a few years of these things running in every home....
-- look, cheese ahoy!
I almost tried to answer, nice trolling!
-- look, cheese ahoy!
No arguments, irrelevant facts and name calling -- You have a bright political future.
-- look, cheese ahoy!
I was stunned by reading the article refered to. Was there a 35-year hibernation period?
In the 1963-65 period I worked on thermal and gas flow analysis for a closed cycle merchant ship application of reactor technology developed during the Aircraft Nuclear Propulsion Project (canceled in 1961; on which I had also worked). It was to use helium coolant.
There were politcal and technological factors, of which I only had a marginal awareness, which resulted in the design never being built.
To find the concept revived, even with a somewhat different reactor design, is startling. Was the previous work forgotten? What motivated bringing the concept back to life after 35 years?
We were well aware of the German work on the Pebble Bed Reactor. We spoke of it as the gumball machine reactor. Was there a similar 35 year hiatus for the concept, or has it been on the back burner for the Germans all these years?
Stunned, inquiring mind would really like to know.
Zeinfeld may be right about the causes of the Chernobyl and Three-Mile Island accidents. Maybe the Russians had only 2D codes, but my memory is that the US had been using 3D codes for some time.
The Chernobyl accident, from what I have read, was due to managers trying a supremely stupid experiment with no engineers present in the control room; they turned off the reactor coolant flow! They supposedly thought they had a reason to try this, but the result was a major disaster which any nuclear engineer could have told them would happen.
As I thought I recalled in the Three-Mile Island accident, there was a recently identified interaction beween pumps, valves, and gauges which could lead to an operator to misinterpret a reading. Unfortunately, as the tale went, the bulletin (or whatever is was called) which detailed the interaction had not been read and understood by the Three-mile Island crew before they experienced this interaction.
I anticipate that Feinman will correct me if I'm wrong about his simplistic (IMHO) summary.
Canada designed and built small scale reactors many years ago (called the Slowpoke), with the intention of them being used domestically in remote northern communities, and for export to third world countries without the money for more complex infrastructure.
As mentioned elsewhere, the general anti-nuclear political atmosphere has eliminated any chance of them making it to market.
My great uncle, who lives near Johannesburg, has had one for ages. I've stayed there a few times, and I came very quickly to the conclusion that it's not economically viable.
Numbers please.
The initial installation cost, maintenance and insurance outweigh the financial benefits of having your own nuclear fission power plant in the back yard.
Numbers? And is this a PBMR-type reactor, or something completely unrelated to the story?
They use lots of electricity during the day time for cooking, computers, stereo equipment, and of course the air-conditioning. But they don't have a single light-bulb in the house.
Sounds like a great story, but if "[e]verything glows in the dark", how do most of the electronics you've mentioned above remain functional?
Everything glows in the dark anyway, so there's absolutely no need for lighting. In fact, only the other day I was bemoaning the fact the I lost a floppy disk under the bed (must have got kicked under there somehow), and that it was alright for him, it would show up in the dark becuase of it's radioactivity. What are you on about he exclaimed exasperatedly, Maybe in the first two months of us having it, yes, but after that the floor glows, the bed glows, the disk glows, we glow, how the hell do you spot a glowing thing amongst a whole host of other glowing things! Besides, I have to keep floppies in lead-lined boxes, to say nothing of the case of my computer!
If _everything_ glows as you claim, more than just the contents of the house would glow. Have the neighbours (or local airport authority) not complained of this?
If it's so fscking dangerous, why do you go back, repeatedly? And why is your uncle still living there?
Currently, my uncle is suing the insurance company, as they won't pay for his chemotherapy
He who fails to read documents he signs should not blame his power source...
(he has developed a malignant tumour, in fact several).
So do a lot of people. Coincidence does not imply causation!
He's also being prosecuted by the hospital,
Wow, the hospitals in/near Johannesburg have the authority to bring criminal proceedings? I learn something new every day...
after a nurse explained that his radiotherapy treatment involved being bombarded with radiation - she needed 85 stitches in the end I think, and is just returning to full fitness.
Your uncle going postal or being unable to conduct himself in a civilised manner has nothing to do with his nuclear power source (if he has one, which, from your story, I doubt).
You've cited nothing about the economics of operating a personal nuclear reactor and have somehow used your uncle's follies to justify the bad economics of personal nuclear reactors.
No, I take that back. You have proven your point. His reactor affected your ability to argue coherently more than I gave it credit for.
There are 1.1... kinds of people.
One note on alternative energy sources: remember, we're allowed to use more than one :) For example, wind and solar often complement each other nicely. And no, they're not as inconstant (trans: unreliable) as you think. There's no sun half the day, but when it's up, solar works.
Of course, there should always be redundancy - more than one power source for those days when one kind or other doesn't work. Fossil fuels should still be used if needed, but what's wrong with using cleaner sources of energy first?
The economics depend critically on load factor, the percentage of theoretical output you get in practice. Didn't the Fort St. Vrain advanced gas-cooled reactor have serious reliability problems? If these micro-reactors
As I was saying before I was so rudely interrupted, if these microreactors don't stay up 24x7, then the capital costs will eat them alive.
I remember reading that one of the old editors of 'Analog' magazine (a sci-fi story magazine) in the 30s/40s put in one of the brief blurbs at the bottom of pages something to the effect "Uranium 238 is being looked at to instantly power on televisions". He was later visited by the FBI...
Where's my uranium powered television?
Arthropoid, the Right Clam for the Job
Southern California Edison is already testing microturbines: small, clean-burning natural-gas power plants that cost a relatively inexpensive $25,000 to $200,000 to build, depending on size.
Sorry, but that $25,000 figure just feels wrong. You couldn't buy the land to put the thing on for $25,000. I might believe $250,000 to $2,000,000.
What's the source of your information?
I worked in a coal-fired thermogenerating station a couple of summers, and my dad worked in the industry for years. You would be surprised by how efficient these large power-generating systems can be. I believe they are extracting 80% of the energy in the coal. This is as compare to like 40%
for a car engine.
The fireball in the boiler heats water to steam. It then is superheated at the top of the boiler (high pressure). This superheated steam runs the highpressure side of the turbine where most of the energy is extracted. The input steam pipes actually glow cherry red. This pulls out a lot of energy. That steam is run through the boiler again (I believe) and back into the low pressure side of the turbine to pull out the last bits of energy.
The "steam" is then run through a condenser so that the nice clean water can go back through the cycle again (saves on water treatment). The pressure in the condenser is *lower* than one atmosphere. They got "all" the energy out. They even use steam pressure to run pumps and things. The big fan motors (input draft, output draft) are 3-phase electric jobs about 3000 horsepower!
OK. So where are the losses? In the generator? Well, there is no water cooling on either the turbine or the generator (which is directly connected). The steam cools itself "cools" the turbine. The generator has air blown throw, I believe. It creates a lot of ozone, so is a safety risk to the workers. Neither the turbine, nor the generator burns up with heat, just to-air heat-exchange. Same with the big fan motors. Pretty low losses of efficiency considering.
So the only real "losses" are cooling water in the condenser, and heat up the stack. The cooling pond stays thawed through a Canadian winter, but it is not that big a pond.
I've never stuck my hand in the exhaust stack, so I don't know how much heat goes up there. I have walked around the top of the boiler. Things are insulated of course, but it only gets around 100 degrees farenheit.
Then there are losses in the transmission lines, transformers, etc. That's why people argue about building close to the consumer. There is supposed to be a *lot* of loss over the high tension lines. Where a "lot" is probably 10-20%, or something "expensive". They don't burn up either, so how bad can it be?
Please don't discount the quality of the engineering that goes into the steam-mechanical-electrical cycle. I've heard that direct fuel-to-electrical fuel cells are *less* efficient than a car engine at extracting energy. And look at how much better the thermo-generating plants are than a car.
Darrin
Has everyone forgotten about Philo T. Farnsworth's fusor?
A table-top fusion reactor using IEC. See this page for more information:
http://fus.x0r.com
Paul Anderson
"I drank WHAT?!" -- Socrates
I noticed that this article is published in a magazine owned by the Washington Times. They are, or at least were, owned by the Rev. Sun Myung Moon (the Moonies. Anyone know if this is still the case?
=-+
This kind of language might cut it around the marketing water cooler, but you should know better that to use generalities like this around Slashdot. (And you actually have the audacity to call the PRESIDENT an idiot?) Wow.
Let's refresh.
-If I'm correct, we're not even sure where 'mass' comes from (see http://slashdot.org/articles/00/09/07/019206.shtml ) ... note that Scientists BELIEVE they MIGHT have found evidence. We're not sure yet. More news at eleven.
r rison/DoubleSlit/DoubleSlit.html. Hmmm.... It still hasn't been explained. He's also known for telling his students that 'anyone who says they know how the world works is lying to you'.
-Einstein (a guy you might have heard of while you had your nose in a book) says that the idea of electrons spontaneously exchanging themselves between atoms is 'funny action at a distance' (at best).
-Richard Feynman (a well respected man that I would go so far as to say was brilliant) came up with a rather curious finding about light particles that is described on the web at http://www.upscale.utoronto.ca/GeneralInterest/Ha
I could go on.
I won't.
And you actually said 'behavior of atoms being pretty well known'. Geez. Sounds good on paper, but you really shouldn't utter things like that.
Yes, even you (and I!) can easily become flamebait on /.
It is all a point of view.
------------------------------
There is very little new in the Nuclear industry. Most serious development was done in the '50s and '60s. Anything that makes the news these days is just a bit of underfunded progressive development.
------------------------------
[These are serious documents so don't bother looking unless you're serious about the issues]
It's the end of the world as we know it, and I feel fine.
I had the same thoughts, but then I recalled some of the facts about Chernobyl. I don't recall the exact radius of uninhabitable land, but it is a fairly huge area, and it is quite possible both Philadelphia and New York City would have to be abandoned if TMI were to go up in a big way. Of course, considering the fact that TMI rests on a river emptying into the Chesapeake Bay, Baltimore and Washington D.C. would not go untouched either.
Basically, there was a reason TMI was a big deal, since a VERY large portion of the US East Coast population would have been in danger.
-={(Astynax)}=-
-={(Astynax)}=-
"Darkness beyond Twilight"
--
YOU! I want that DeLorean. I cant afford one :P
> Do we really want to cause the death of an industry for the sake of cheap electricity?
Industries shouldn't be kept around just because they currently exist. It's inefficient, and a bad way to rationalize any decision. Cheap electricity would benfit people far more than the temporary inconvenience it would cause people in the power industry, although, as you pointed out, there are serious dangers that come up. The dangers are reason enough to go against walkman fisson reactors.
OddManIn: A Game of guns and game theory.
power is extremely safe because it is highly regulated
And who will regulate Billy-Bob's third hand fission box that is rusting just outside his double-wide?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ the real world is much simpler ~~
--- -- - -
Give me LIBERTY, or give me a check.
is that your picture there? You certainly don't look Chinese. Interestingly I am from Taipei too but grew up in Toronto, Canada. Haven't been back since; I heard everything has changed.
sure I'll have a sig.
You might want to have a look at the Oklo Fossil Nuclear Reactor, the product of a natural nuclear reactor in Gabon. It's thought that, about 2000 million years ago, a water moderated chain reaction started in uranium rich soil and ran for about 1 million years. (How do they know, well there's all these fission products lying about the place.)
Agreed, but it is less chemically toxic than many other natural toxins. Botulism toxin is, I believe, top of the league table here. (And people inject this stuff into their foreheads!)
This 100,000 years number seems to pop up with wild abandon. IIRC, this figure appears to be the half-life of one of the daughter products of the decay chain. But with a longer half-life comes less activity. How close is this to background radiation? And does it make more difference to radiation exposure than, for example, living at 700m above sea-level does?
None of the above is an argument for not treating nuclear waste carefully. But requiring massively different standards of risk control when the nuclear word is used doesn't help anyone. And it may be actively harmful: Opposition to nuclear power has led to more coal being used for base-line power production, leading to massive amounts of chemical and radioactive pollutants being spewed into the atmosphere. Not something I feel particularly comfortable about.
Well, I hope they got a visit from their regulatory authorities. No proper waste handling, just leaving it in the ground with water running over it. Given the shape of the reactors, no containment buildings. And all that unused uranium lying about the place when they were finished. And water moderated, too; you'ld have thought that they sailed through space in caravels.
Shocking. Simply shocking.
Oh, that makes me feel so much more comfortable, only well over a hundred generations of people are going to have to deal with this, not thousands of generations.
"Giving money and power to government is like giving whiskey and car keys to teenage boys" P. J. O'Rourke
You obviously haven't tried putting that in front of my boss!! I'm sure with all the stuff he spouts he could power most of the west coast!
If this does become a reality, datacenters will be popping up all over the place.
Blow me.
Unless I'm severely mistaken, small-scale piles like this have been around since the 50s...I don't know...
I have a girlfriend whose name doesn't end in
Boss, if you think any politician, with the possible exception of Nader, is not in the pocket of the energy companies, I have an infinite series of cliches for you.
Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
Society drives politicians at the ballot box and the poll. Politicians can thrown on Helmet, Aftertaste, and crank up "Just Exactly What You Wanted" with confidence.
Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
You fucking idiots, for God's sake are you ALL American?
I was joking! Of course my fucking uncle doesn't have a nuclear reactor in his yard! Of course he doesn't! How can he have had a nuclear reactor in his background for years?
You know, sometimes I wonder about you folk. You really ARE dumb aren't you. Still, reminds me to stay in England, where sarcasm isn't just a word in a dictionary.
Now if I can just get that Flux capacitor and Mr. Fission gigawatt generator working....
live the dream-- drive stainless!
"You may all go to hell and I will go to Texas"
Sen. Davy Crocket to US Congress, Nov. 1, 1835
We're never going to have our own power stations when big corps. can product it, and sell it to us. If you are one of us that doesn't want to be Edison International's bitch than bit the bullet and get solar panels. They have improved a great deal, so you';ve got no reason not to... For some reason people just DON'T... Apparently it's in-vogue to complain. :-\
A bit offtopic here: I like the junkscience.com site, but when they say Gamma radiation is what you get from an X-ray, I begin to wonder. Anyone who has taken high-school physics should know that X-rays and Gamma rays take up two separate chunks of the spectrum, just like IR and UV. Yeah, it's nitpicky,but I expect better out of a them.
GC-mass spect, FTIR! RI, UV, NMR! I'm a spectroscopy whore! Yeah team!
"Cheeze it!" - Bender
localroger wrote:
[Would it be possible to make a mostly clean H-bomb by removing the depleted uranium? Just a thought.]
Yes, it would. It would be another animal entirely, though; the neutrons created by the fusion reaction have to do something. So when you replace the tamper in an H-bomb with something that won't fission, you get what is called a neutron bomb.
I'm sure you've heard of them.
Clean nukes are made with a lead tamper. They are useful for excavation work and for recovering oil from oil shale.
-Nukebuddy
doorbot.com wrote:
So that leaves us with dams and nuclear power (fission) as our clean energy sources...
Damming is the dirtiest power source. It's true that nuclear is the cleanest, though.
-nukebuddy
The waste from nuclear reactors and reprocessing is in no way comparable to what is present in nature. It is very chemically toxic and emits far more radiation per unit time. By the same token its radiation will burn itself out in a relatively short term compared to geological radioactive sources, but it will still be worrisome to deal with for something like 100,000 years.
Brackets contain world's first nanosig, highly magnified:[.]
Anyway, I've done a bit of reading on this as well and experiments with this have been done, albeit I think pumping in radioactive liquid waste. This had the unfortunate side effect of lubricating the plates and causing slip. Plate slip is an earthquake.
My understanding is that containment isn't completely impossible and that present containment vessels are insanely overengineered. (Which is good, I'm all for overengineering and think its a bit of a misnomer if the risks are high enough).
There are a few difficulties though, one is that not all the radiation is contained, particles escape and if they're deadly enough (think plutonium) cancer is going to happen. This is true for coal fired plants as well though, and cancer incidence around a coal fired plant is higher than around a nuclear plant. Another is public involvement. It's sort of like prisons, lots of people think that the war on drugs is a good thing even if it means a few more prisons. Nobody wants the new prison in their neighbourhood though. The same goes for actually transporting the waste through neighbourhoods.
Chris Kuivenhoven is a thief, beware
The automobile was invented, marketed and became pervasive. This had a huge negative impact on passenger trains. This in turn all but destroyed an occupation: porters.
Prior to municipal waste plants people relied on outhouses for their facilities. This technology killed a couple of occupations as well. First, there was the person who's task in life was emptying out the holding trays of the outhouses. Second was the person who would take this effluent and produce pottasium nitrate from it.
Skeptisism is a good thing, but being a luddite isn't. There are a huge number of reasons to worry about nuclear power as well as a huge number of reasons on why its actually cleaner and safer than traditional coal fired plants. I'm not sure where my personal stance is at this point, though I have worked in a nuclear reactor (a CANDU reactor at Pickering Ontario) and probably am familiar with more of both sides of the equation than most people.
Chris Kuivenhoven is a thief, beware
I read that JunkScience.com has an awful lot of "news" from FOXNEWS.com. Might as well call this "JunkScience - By JunkFOXNEWS - Illiterate Sensationalism at its Finest" FOXNEWS - Where the morons get their news fed to them with a heaping helping of Rupert Murdoch Right-Wing propaganda.
"Face it, a nation that maintains a 72% approval rating on George W. Bush is a nation with a very loose grip on reality.
You mean they make malt liquor in France? If "Joe" can't find a job, why is he spending his evenings watching television? Why is he buying designer jeans instead of clothing that is more suitable for a job interview? 300,000 unemployed software engineers in India is a testament to the effects of 50 years of bureaucracy, border wars, and protectionism in India. The software industry here is a direct result of restraint on the part of our own slightly more competent government.
snore.......
Put more work into making your conspiracy theories more entertaining next time. At least the Holocaust revisionists put some gashdarn OOMPH into their efforts.
everyone who is concerned about someone 'reverse engineering' one of these 'mini-reactors' can put their mind at rest because the DMCA will stop them dead in their tracks. -ziggens-
The temperature difference only determines the thermodynamic, theoretical maximum efficiency of a heat engine. A nuclear power plant is a far cry from this. Fusion will not help you when dealing with isotopes heavier than iron. The waste that today's generators produce are all heavier than iron. I don't thing neutron bombardment has proven effective.
Dealing with spent fuel isn't the whole matter. Refueling a nuclear power plant generates waste fuel, but decommissioning a nuclear power plant generates an incredible amount of radioactively contaminated waste. The entire system used to contain the fuel is contaminated, and even if it could be decontaminated, it is not permissible to recycle the scrap metal for a "conventional" purpose (i.e. your silverware was never a reactor pressure vessel).
So we have to address the issue that we will eventually have to scrap these millions of in-home reactors at the end of their service life. Not a pretty picture.
There are also military concerns about giving everybody fissile material.
"Hey bob, can I call you back? Yeah, my reactor is leaking in the basement again."
I smell a wumpus! [S]hoot or [M]ove ->
Depends what form you want your energy in. We tend to think of the electricity as being the good stuff, and the heat as the bad stuff, because we generally just radiate excess heat away to cool the steam/helium.
However, get this reactor small enough and you could heat domestic/industrial water with the excess, like they already do in Iceland with geothermal sinks.
If you were blocking sigs, you wouldn't have to read this.
That's pretty short sighted for people who should be thinking 100,000 years or so down the line. Or am I being naive? I know our current strategy is to bury nuke waste with a "Do not open until Christmas 102,001AD" sign on it, but I'd like to believe that someone in the nuke industry is thinking beyond their next set of stock options.
How long are hydrocarbon fossil fuels (coal, oil, gas) going to last? 500 years? 100? 50? 20? And when they go, what's the population going to be? 10 billion? 50 billion? Where's the space for wind/wave/solar/GM alcohol crop farms going to come from, considering that we're currently hacking down the last of the rainforest to make Mooby Burgers.
In the mid term, nuclear is going to be a necessity. When the choice comes down to nuclear or nothing, it won't be a choice at all, and the tree (stump) huggers will have to find something new to misunderstand and bitch about. However, I fully expect that we'll wait until we've got 5 years of exploitable oil left before building nuke stations in sufficient numbers. Better to start now, and this looks like a decent next step.
If you were blocking sigs, you wouldn't have to read this.
Yeah, right. I wonder why the people running current nuclear reactors keep storing all that stuff? Why don't they just put it back underground?
Yes, why don't they?
Because there isn't a safe and economical way to reduce its radioactivity to background levels, and people living near proposed burial sites of highly radioactive waste are naturally sceptical of the ability to contain it for several thousand years. There's also a tremendous lack of trust (see this site, for example) of the parties responsible for disposing of the waste. Do you believe that the corporations and bureaucrats disposing of waste wouldn't cheat if they thought they could get away with it?
I've been trying to find numbers about the relative radioactivity of uranium fuel rods before and after use. The only number I could find in my intensive 15 minutes of research (;-) is that the spent rods are "millions of times more radioactive" than fresh fuel. That site didn't sound terribly reliable from a scientific point of view, but if spent fuel is at all more radioactive than fresh fuel, you couldn't put it back in the same place without raising the levels there. Maybe someone who knows what the numbers really are can chip in here.
In addition, these PMBR balls are radioactive. We'd be handing terrorists their dream. Radioactive easily obtainable pellets. Dirty bombs anyone? These PMBR balls would be perfect weapons.
I posted and all I got was this stupid sig
And I belive that the canvas-like material that was coating it was nitrocellulose. As in the stuff gun-cotton is made of.
The author of the piece was being too optimistic about how small the reactors can be made. The issue isn't so much the core of the reactor, but the necessary neautron shielding. Nuke submarines use a layer of borated polyethylene to slow down and absorb neutrons.
As another poster pointed out, the gas turbine cycle was originally promoted by General Atomics. They were using graphite prisms as opposed to the pebble bed.
Don't see much practicality below the few MW range.
A Shadeless room is a brighter room.
yeah, 'dope it with Fe', a energy figure taken from the sky, and 'how about the millions of people working in the power industry'.... Man, WHAT a troll! I'm surprised it went through. Notice the statement about hydrogen bomb - it was perfectly trollish! Some people will invariably try correcting it, saying that hydrogen bombs use fusion, and others will point out that he correctly said fission _powers_ (starts) the fusion.
-- Cure for Cancer instead of SETI! (only w32 yet - mail and beg)
I agree that fission power *can* be an environmentally sound source of energy production. It certainly can be much less harmful to the environment than hydropower- dams in Washington state have devastated the salmon, and elsewhere have destroyed many habitats. Dams also eventually silt up and become useless. (check out the book Cadillac Desert by Mark Reisner)
It is important however to have heavy regulation by a citizen-responsible branch of the goverment- past regulation has been lax, and energy companies have been very irresponsible (check out the movie China Syndrome- screenplay was written by a nuclear engineer) Also, the cost of waste disposal has to be part of the cost of energy production. Nuclear waste is a huge issue, but I don't think people realize that most nuclear waste comes from weapons production (in the U.S.).
As to the cause of Chernobyl, I think a couple of factors heavily contributed to that disaster: 1) unsafe reactor design- graphite moderator based reactor for both weapons fuel and power production, 2) poor funding- demoralized workforce, poor training, etc (Chernobyl Disaster). The problem with fusion is not that it's not economical, it's that we don't have a working fusion powerplant. What we need (at least in the U.S.) is agressive funding for fusion power. I don't think the oil companies are too keen on this- and currently they seem to have even more influence (i.e. Prez G.W. Bush).
The USA renounced reprocessing for non-proliferation reasons. The USA is actually alone among the Nuclear Powers in this. The French run a reprocessing facility for themselves and for other countries (UK, Germany, Japan), and Russia has offered to reprocess commercial waste for other countries.
You are confusing fission with fusion.
So some general remarks are in order:
Fission is the reaction which powers nuclear bombs and power plants. The energy comes from spliting of Plutonium or Uranium nuclei into lighter nuclei. Fission can work in a chain reaction because usually spliting of heavy nucleous produces neutrons which in turn can split other nuclei.
On the other hand fusion is the reaction which powers H bombs and stars. In fusion 2 lighter nuclei combine to form a havier nucleous. Unlike fission, there is no fusion chain reaction (more or less). Further, using current technology, fusion is to be produced in tokamak, which is a self stabilizing system! In the sense that reaction will never run away. Tokamaks work by confining high temperature plasma with magnetic field. The nuclei in plasma fuse because of collisions due to high temperature in the said plasma. If reaction is going too well, the plasma temperature gets too high, and magnetic field becomes too weak to confine the plasma, causing the plasma to leak out and reaction to stop.
Unfortunatly fusion has major drawback: there are no working reactors!
Also fusion is not as clean as claimed, and you are right to be worried. The easiest way to fusion is the Deuterium-Tritium reaction, unfortunatly it produces a large number of neutrons. The neutrons are ofcause the major problem with all nuclear power and are very harmfull to humans. The neutrons cause formation of unstable isotopes in everything surrounding the reactor making it neccessary to dispose of core and shielding not just the spent fuel.
So fusion will not solve any problems here on Earth. Hopefully, controlled fusion will be allowed into space since the reactor and fuel are "clean" until turned on, where it will be a very useful power source. The only thing better would be antimatter, but that is even harder to get to work.
David
Uh, I know a lot about South Africa. What does that have to do with poor countries invesing in fission reactors? And yes: South Africa is a POOR COUNTRY.
Where did I say the USA is perfect? I don't even live in the US.
Wierdo.
Extremely rare and not what the original poster was thinking of.
Normally this is not the case.
You can get the hydrogen from petrol, methanol, natural gas or a variety of other sources.
I didn't say fuel cells generate "new power". Fisson doesn't generate "new power" either.
The fact is that fuel cells will work simply (low maintenance) and safely in these situations. Nuclear power cannot.
Granted you have to get your hands on some natural gas, but fission doesn't happen out of the aether either.
Radioactive elements don't sit around in nature in big chunks giving off massive amounts of radiation as spent fuel does.
BTW, the idea of poor countries investing in FISSION REACTORS is laughable. I've never heard of this magazine, and I hope I never hear of it again.
Think fuel cells.
Thx bye!
Not Meta-modding due to apathy.
This is not news.
When controlled fission was developed in the 50's, there was rampant speculation that every home would be fitted with a fission plant, and that clean, reliable energy would be available on demand, at such low cost that it would be "too cheap to meter". (There were all kinds of other "Atoms for Peace" projects proposed, such as using nuclear bombs to excavate artificial harbours and divert rivers.)
The problem is that any kind of practical fission produces isotopes which give off a tremendous amount of radiation and which have to be buried for thousands of years. The site has been slashdotted, but I can't imagine that they've found a way around this problem.
Imagine the fun when a curious six-year-old takes Daddy's screwdriver and tries to see how the basement fission plant works.
Toronto-area transit rider? Rate your ride.
Only tropical dams have this problem with the release of CO2 when the flooded vegetation rots. Dams built in colder climates release C02 much more slowly (in northern Canda, resevoirs release virtually no CO2), and if the area to be flooded is cleared first it greatly reduces the problem.
Anarchists never rule
Well, if you want to get technical about it, only if you're talking about atoms and the usual isotopes. An isotope can have any number of neutrons and still be considered "helium" as long as it has two and only two protons. And if there's no electrons, then couldn't we call it a helium ion? :)
Gee....
That reminds me of the generations before us.
There has been problems in every generation, as far back as you'd want to go, that the people said "well........ we don't know what to do with it.... lets let the kids figure it out when they get to it."
IMHO, thats pretty fucked up. We need to find a feasable solution, and not shrug the responsibilty onto the next generation.
My $0.02.
Deus Ex Machina
If you see me running, try and keep up
There's a good chance I don't know what the hell I'm talking about
At about the exact moment that all the panicing nellies got the nations (US) neuclar power program killed because of chernobil (sp?) (even tho we in this country were never stupid enough to cool our reactors with something flamable like graphite) some woman (I forget her name) had figured out a way to make a full-sized and fully fueled breeder reactor eat its own waste down to like a fist-sized result. The process was effecient enough to make it practical to take our existing waste and re-fuel a reactor with it to get rid of it.
Good thing all those smart protesters out there wisely protected us from a mature neuclar technology...
--
Rob White,
Cv - Cv = 0 Therefore there is an absolute frame of reference.
Innocent people shouldn't be forced to pay for inferior software development.
--"Code Complete" Microsoft Press
There is no such thing as Nuclear pollution. If you look back a 100 years ago, natural gas was thought to be "pollution" left over from oil drilling. Now that natural gas has a use, it is a valuable resource. Consider that long range space probes generate power by converting radiation to electricity. Plutonium is normally used due to it's high radioactivity to mass. Fill a large generator box with nuclear waste, generating electricity from radioactivity. Then the box is full of nuclear fuel, not waste as it is being used to generate power. And, if it is locked in a boz generating power, then you can't call it pollution. Funny way to store radiactive waste, in every home generating clean power.
I think the U.S. gov't had no idea what it was unleashing upon Hiroshima. It new it had a destructive weapon, that could be deployed by one aircraft, and that could destroy an entire city, but not that it would be so incredibly dangerous. They made the correct choice based upon the circumstances, and in the end saved millions of American and Japanese lives.
Watch out for them damn Hobbits!
Ideas like the one described in the article are not new. Every few years, someone else comes up with the idea of so called safe minireactors to harness the demon of nuclear energy.
However, the core problem is never actually touched or discussed. Noone on this planet has yet found a way to dispose of the nuclear waste that reactors (Of any size!) inevitably produce. Waste that is so toxic and dangeorus it may never, ever come in contact with the environoment. Waste that has to be cooled and maintained for several ten thousand years - that is far longer than humanity exists on this planet.
Alone the idea of producing more of this waste is scaring me shitless, for anyone who has looked deeper into this topic will surely feel the same.
About the pebble pile type of core: The fuel elements as well as the reflector of the reactor are made of graphite. Graphite is chemically carbon, wich means the stuff can burn. In a reactor of this type, it is common for the fuel elemets to reach temperatures about 1200 deg. Celsius, so they will ignite and burn the very moment they come in contact with oxygen.
So, if the reactor is ruptured, you have the same situation like in chernobyl - a burning lump of graphite that distributes the radioactive substances nicely into the atmosphere, creating a cloud of highly radioactive and toxic fallout that is able to render large areas uninhabitable for decades.
In Germany (that's where I live) there has been an attempt to build a large-scale reactor following the pebble bed principle, the THTR (Thorium high-temperature reactor). It was lauded as reactor type that could deliver high-quality process heat for the chemical industry as well as electric energy. The reactor never got out of the test phase, and was shut down permanently after only a couple of days of running, because there were enourmous problems with the fuel elemets that tended to break up.
Now if such a ball breaks up, radioactive dust (both graphite and fuel) contaminates the gas cycle and requiering shielding for the turbines as well, and making repairs very difficult. Also, the intense neutron radiation led to unpredicted effects in the material of the pressure vessel, quickly lowering its stability.
All in all, the concept has proven even harder to handle than the conventional pressurized-water type of reactor, wich already poses so many unresolved threats that most ppl agree that the risk of running such a plant is simply too high to accept. I personally fear the day these machines are built and put into operation because every single of them is an accident that only waits to happen. And an accident must not happen, the consequences of one we have seen at chernobyl.
Reality is for those who can't face science fiction. -Lisanne Norman-
You must be talking about the "Nuke Train" that was rollin' through Nevada & California all loaded up with nuc-waste sent on its merry way through the most rikety high mountain tracks imaginable only days after a major storm. Just put your blinders on and GO!
Good point. Security is just as big an issue as the radioactivity. Who is going to guard all of these subduction zones filled with pellitized nuclear waste? It's basically free to whoever can unbury it from it's watery crypt. Just an innocent fishing boat passing by? Think again. Are we really going to be able to guard an ocean site from above for 30 years or more? Too impractical. Best to re-use the waste in more efficient burn-all retro-fitted reactors (we aren't likely to see too many new reactors in the U.S). And in the meantime, keep the waste underground.
Great! I would like you, then, to estimate the cost of everything you buy using that methodology and pay the difference between that price and the price it's been marked at to one or more organizations that are doing said cleanup work. Accordingly, when you buy a gallon of gasoline for $2, I expect you to send the Sierra Club or some similar organization $5. When you pay your $50 electric bill, I expect you to send $80 to repair damaged river systems. And so on. If you are doing this already, I applaud your honesty and integrity (though I question your intelligence). If you are not, then begone with you, for you are nothing but a hypocrite. Do not expect others to pay when you are not yourself willing.
I'm living in California...the reason for the so-called electricity crisis is none other than hypocrisy. Those who oppose the construction of generation facilities should have their power turned off first. When that law is passed, I expect very little opposition to such construction. In a democracy, it's easy to protest this and that without it having much effect on you personally, because you know that if your viewpoint makes it into law, the vast majority of the cost will be borne by others (who may or may not agree with you) simply because there are more people who are not you (millions) than who are (1). When the minority of complainers suddenly has to foot the entire bill for its ideals the game changes - suddenly a "social conscience" isn't so popular a thing to have.
This is a fundamental problem with the type of government most advanced nations have. I don't have a real solution (well, I do, but it involves replacing this form of government with a much different one). In the meantime, it might be of interest to consider that the externalities usually thought to be the reason environmental damage occurs in the first place are just as much an issue in the fight against it. After all, how much does it cost you to protest the construction of an electricity generation facility? How much does it cost others when your protest succeeds? That scenario is the definition of an externality.
ess people out of work = less crime less people out of work = a larger consumer market
You're forgetting, cheap energy = lower production cost. Lower production cost = lower consumer cost (in a healthy market), lower consumer cost = higher demand. Higher demand = expanded production. Expanded production = more jobs.
In what way?
Imagine we were all still riding around in horsedrawn buggies because we didn't want to seriously reduce the demand for: buggy whip makers, street cleaners, horse breaders, blacksmiths, veterinarians, etc, etc.
Also, considering that the most likely deployment of these reactors will be in the elefctrical generation industry, I fail to see how the workers will be displaced. They will just get some additional safety training (I hope!) and go from working on gas turbines powered by natural gas to gas turbines powered by fission.
I have two major objections to the use of nuclear power. The liklihood of a core accident and waste handling.
This system appears to answer my first concern. Unlike most reactors in use in the U.S. this one seems to be intrinsically stable under failure conditions. (I would certainly classify total loss of coolant a failure state!).
The real question is waste handling. It seems that the fuel design will keep the waste contained over the operational life of the fuel. The question is processing after use. Are the pebbles to be somehow disassembled and reprocessed (possably after a cooldown period) or will they be disposed of as is? How long will the pebbles contain the fission products after use? Any possability of using their intrinsic heat generation for a smaller scane energy production (perhaps using sterling engines to extract useful power)?
I suspect that in the real world, their careful handling will extend exactly as far as their useful life + public oversite. After that, they will be disposed of in the cheapest possable way w/o reguard to long term safety. It's the american way.
If the pebbles are intrinsically sound enough containment for long term storage and preferably useful for secondary energy production, this could be feasible and at least no more destructive to the environment than current fossil fuel use.
> A Nevada resident with more than enough power from zero emmissions Hoover Dam.
You don't get nearly enough from the Hoover Dam. IIRC, Nevada only gets 25% of the power from Hoover Dam, which only covers 13% of Las Vegas's power needs. Even if you somehow got the California and Arizona to relinguish their share of the power from Hoover Dam, that still wouldn't cover Las Vegas's power needs. The lion's share of Nevada's power comes from fossil fuels.
Not only do you get power for your house, but as a by-product, you can use the waste heat to heat your pool, and the Cerenkov radiation will light it at night!
Just don't go in the deep end!
Actually, looking into an operating nuclear reactor is an eye-opening experience. If you live near a university with a reactor, chances are they have a tour of it every now and then. It becomes far less scary when you can see it.
Would you rather have another Chernobyl, or another Venus?
"The Idiot is a diversion, mind the crooks in the background."
That's a *very* intriguing idea, metis. Please, expand upon it!
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Hmmm... and didn't humans most likely evolve in South Africa?
I wonder if we're all nuclear babies...
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And now we have another example of technical overconfidence. Fission power may well turn out to be useful in many ways, but it will not be solve the thrird world and california's energy problems. It will also be dangerous.
Traditional nuclear power comes from fission, the breaking apart of atoms. It isn't anything new. Nobody is talking about fusion, the combining of atoms.
Fission power is what fuels the hydrogen bomb, and we are proposing that we put fission reactors in everyone's home?
Well, except you nobody is talking about fusion. The hydrogen bomb is fussion based, NOT FISSION. It combines hydrogen atoms together - it fuses them. The older atomic bombs America dropped in World War I were fission.
I suppose to be technical there is fission in a hydrogen bomb used to set off the fusion reaction, but it isn't the main source of the explosive power. That is the fusion.
So the artical is talking about the same reaction used in current power plants, just scaled down.
Ben
The only way to sustainably use fission is to make plutonium in breeder reactors and then use that, isn't it? Additionally, isn't plutonium about the nastiest stuff you can ever deal with?
Go you big red fire engine!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
for the obvious reason - if you're selling enriched uranium at the friendly local corner store, you've just made life a heck of a lot easier for your friendly local terrorists to build a nuclear weapon. Yes, I am aware that there's more to it than that (for instance, you need an enrichment plant to produce near-pure U235, quite a bit of knowledge about conventional explosives to trigger it, particularly if you're going to use an implosion design, etc. etc. etc.), but having a supply of uranium is a necessary prerequisite, and it's something that is currently at least somewhat difficult to obtain.
Go you big red fire engine!
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
I think it's worth mentioning that running nuclear "waste" through again is being done in two places -- in Canada with stuff imported from the USA, and in France imported from Germany. In both cases rapid environmentalists were laying down on the roads to stop it coming in... (in Canada, they flew it in by helicopter instead to get around the block).
I think the biggest issue with small scale nuclear reactor operations is security--the potential for sabotage or theft is a big concern. There are probably groups out there that would sabotage an early pioneering installation, with no regard to loss of human life, to poison the waters for future development.
I agree whole-heartedly :)
I think a better idea would be to take the suggestion that others have made on this thread, and use a liquid-metal reactor that just keeps burning the waste until it's down to practically nothing. It's more energy efficient and cleaner to boot.
Still, as long as people are afraid of a possible china syndrome or chernobyl, this isn't likely to be a very popular solution.
ObJectBridge (GPL'd Java ODMG) needs volunteers.
Finding God in a Dog
Actually, it's fusion, the uniting of two or more atoms of hydrogen isotope into helium, that powers the hydrogen bomb. Fission, the splitting of the atom into smaller atoms, is what powers all those nuclear bombs that are sitting in Russian, Chinese, American, etc. silos, waiting to destroy us all.
Just a minor point, but I thought it might help to clarify just what we should all be skeptical of here.
Why not? The biggest problem with the modern electrical system, imo, is transmission and distribution. Fuck it; if we can produce our own power, let the power companies wither on the vine. In many cases, they richly deserve it.
I agree, for different reasons (such as: what do we do with the nuclear waste???). Although I adamantly believe that nuclear power is nowhere nearly as evil as the present practise of burning fossil fuels to produce electricity.
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Finding God in a Dog
It's funny that the proposal comes from South Africa, because there were quite a few natural nuclear ractors nearby, such as in Oklo , in Gabon. (here is a more technical article, and a cross-section diagram, neatly labelled in Japanese). And, of course, you can expect it to be threatened by mining...
(Here is my google search for the stuff).
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That's as long there's no bunch of monkeys running around and undoing by hand what the automatic control system does, like at Three-Mile-Island...
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This is total bunk. That carbon dioxide would be STILL released in the atmosphere if the plants did rot on the ground, were burned (duh?) or eaten (where do you think the carbon dioxyde we exhale comes from?).
It's just fingerpointing by people who don't like dams.
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A signifigant fraction of the heat generated is from the radioactive decay of fission products. For many reactor designs, this decay heat is enough to raise the fuel temperatures to damaging levels if it is not removed.
Noted; thanks for the tip. I'm working under the (perhaps foolish) assumption that current designs and fuel replacement policies are set up to prevent this from being a hazard.
It sounds like you are describing a negative temperature coefficient of reactivity ("negative void coefficient" if you are a civilian). In a water-moderated reactor, an increase in temperature will reduce moderator density therefore cause a tendency for power to decrease. This provides for negative feedback and causes reactor power to change to match the heat removed from the system without operator intervention. This does not prevent an over power condition - it just means that the reactor is inherently stable.
Again, this depends on the design of the reactor. One of the big selling points of the slowpoke was that there was no configuration that would lead to an overpower condition (pull all of the control rods out, and it's still in a stable regime).
Academic in this case, though, because the article wasn't talking about slowpoke reactors (I'd misunderstood initially).
On the off chance that this wasn't just good satire:
Trivial as it may seem, energy gained by tidal power is, erg for erg, slowing down the rotation of the Earth. True right now the results are inconsequential, but if massive projects were undertaken to supply 30% of the Earth's onging power needs with tidal forces, over the long run it could have an impact, and it's not exactly like we have a way to repair the damage by speeding up the Earth's rotation...
There's on the order of 1.0e30-1.0e31 joules of energy stored in the Earth's rotation. That gives us around 30 billion terawatt-years.
I don't think we're in danger of draining it soon.
At least clean fission only eats up matter which, though not a renewable resource either, is constantly being replenished on the order of tons a day from micrometeorites.
...which are made of rock, and thus don't contain much hydrogen. Allegations of a continuing hail of ice micro-comets are as yet unsubstantiated.
Not to worry, though. Even if we just extract deuterium (which is 0.015% of all hydrogen) for fusion, we have about 1.0e13 tonnes of the stuff in the oceans. Assuming around a million times the energy yield of chemical reactions, this gives us about 5 million terawatt-years.
Switch to ordinary hydrogen, and by the time the sun burns out, we'd have used around 15% of the ocean. Assuming we don't ship in a few ice asteroids in the interim.
you dont put your material in barrels and hope it stays there, you encase it in solid glass. that way even as it breaks up the material is still encapsulated. Also most subduction zones are a couple hundred miles off coastlines, and under alot of salt water. You arent going to be drilling there for groundwater any time soon.
I've already been assuming that the barrels are filled with glass pellets. I still wouldn't want the barrels to break. Shatter the beads, and currents will take the resulting dust all over. Disperse a pollutant in the water, and it *won't* just stay in one place - you'll eventually have to worry about it (especially if we're dumping all of a continent's waste, and not just one plant's worth).
If you have a really deep hole, and plug it really well - maybe. But I'd still feel safer with the barrels deep in the continental shield.
The graphite-laced "pebbles" in their reactor could melt down if enough were piled in one place
No, they won't. They are designed to keep the bits of fuel far enough apart that no reaction hot enough to start burning either the fuel itself or its carbon shell could start or sustain itself.
This has actually been tested by running a pebble-bed reactor without coolant for an extended period.
I meant, a pile larger than would fit in the reactor. A large enough pile should indeed melt down. The reaction will increase exponentially if the probability of interaction (vs. escape or absorption) is greater than one divided by the number of child neutrons produced by a reaction.
The probability of absorption (by the graphite or by a nucleus) depends on how far a neutron would have to travel to escape the pile. Use a bigger pile, and there's less chance of the neutron escaping.
If fissile material was sparse enough inside the fuel balls, then you could set it up so that an arbitrarily large pile still wouldn't enter meltdown, but this would make it a lot less useful for generating power as well (a small pile would be very, very subcritical).
if you keep it in a lead box, within another lead box, and allow only authorized technicians to service and maintain it, then I think there wouldnt be much worry as long as everyone does their part safely
And therein lies the biggest problem: you're relying on *everyone* to do their part safely, *all* of the time, for all of the reactors that are ever installed.
One screwup (accidental or delibarate), and you've just astronomically jacked up the cancer rate for everyone in the area for the next 50,000 years or so.
Good luck getting these insured.
The current scheme - using a few big, well-monitored plants - is much safer.
Also, FYI, lead will corrode relatively quickly (and I'm ignoring earthquakes and other disasters).
Wasn't slowpoke (and most early research reactors) water boilers with an aqueous solution of uranyl-sulfate or something? No fuel rods, I think... just a big liquid solution with fuel mixed in.
I'll have to look that up; thanks for the pointer.
My understanding was that at least some versions used fuel rods, but I haven't checked in quite a while.
Lastly, the "slowpoke" style of reactor described can't have runaway heating at all. As it heats up, the core expands, pushing the fuel rods away from each other and making the reactor less efficient.
My mistake, the article refers to a different type of reactor.
The graphite-laced "pebbles" in their reactor could melt down if enough were piled in one place, as graphite will stay put under meltdown temperatures (the fuel, steel, and graphite will alloy with each other and whatever's underneath them as they heat up). The PBMR is thus open to abuse.
A meltdown still won't cause a nuclear explosion. It just makes a hot molten mess that's very radioactive.
There is a solution to the nuclear waste problem, burn it. I dont mean with fire, i mean in a reactor. so called nuclear "waste" is waste because it can no longer be used by a conventional nuclear pwer plant. There are power plant designs that would use fuel rods until all of the fissionable material is used. Look on google for the Advanced Liquid Metal reactor. Fuel is recycled until all the uranium and plutonium has fissioned into lesser elements, some with half lives of days, rather than millions of years.
According to two different descriptions of ALMRs, you only end up burning the heavy waste products (actinides) with this scheme.
Radioactive lighter elements may be bred to something more stable, but stable ligher elements are just as easily bred into medium-lifetime radioactive isotopes.
Aren't there some serious problems with leakage of these containers into the groundwater table? I seem to remember hearing something akin to that...
That depends on where you bury them.
The proposals I've most recently heard about involve either burying them a few miles deep in the Canadian Shield - bedrock that water doesn't flow through - or burying them a few miles deep under the ocean floor, with the holes plugged with clay (which water doesn't flow through readily).
Both should work long enough for most of the products to decay, even if the containers don't last anywhere close to that long. The containers are mainly to protect it during transport and during temporary storage (accidents could have nasty consequences without these precautions).
I would not at all be suprised if Bush accomplishes more that Clinton and Gore on global warming and other fundamental environmental issues. The problem is that the press is willing and able to exploit the slightest bit of hestitation on Bush's because he is a Republican and was previously involved in oil.
Where is it written that the President must do dog and pony shows for the press, especially when they've exhibited such willingness to play up every little slipup. Anyways, I happen to have liked Reagan.
The man lied under oath and had sex with an intern in the White House. If he were the chief executive of any company or even lesser government official he would be gone in a second. Don't even act like Clinton didn't bring it on himself. They couldn't find a thing on the man? Feh. They found out that he perjured himself. As for "finding" stuff, we have this thing called a court of law...it sorta makes things difficult. Clinton is dirty, you can deny it all you want, but he's dirty.
No, Bush clearly knows how to relate to people. That matters in politics. He may not have the rhetorical skills that Clinton has, but those are two entirely different things.
No, other people are running this government, unlike another certain president that thought he was some kind of genius, he didn't try to micromanage. He has very good people and he's using them properly as far as I am concerned.
Education reforms. Military reforms. Taxes. Etc. You may dislike his policy, but he's focused on them. Clinton on the other hand tried to be all things to all people and I frankly thing he didn't accomplish much as a result. If he had focused his energies on a few really important issues, he would have been far more effective.
Yes his policy is largely alligned with mine, though not entirely. Although I couldn't care a rats ass about the Christian right, so to speak, I'd rather have them merely kept in a corner then have someone that is unwilling to, say, make any real changes in education for fear of pissing off the teachers' unions.
Totally unsubstantiated by ANY respectable media source. In fact, such drugs were not even in vogue when he was in school, it's nothing more than a rumor.
Heh what dirty tricks would those be exactly? The one where he gets an endorsement?
Which, by all accounts, can hardly be blamed on him, but rather on the market and lack of oil.
Uh, you do know that the media actually did inspect the ballots and found that even if they used Gore's proposed method, that Bush would have actually PICKED up votes overall? But that's besides the point? What dirty tricks specifically? Prove them.
His people for one. You don't keep staff like that by being an asshole.
Anyways, this is pointless. You may be well to the left, but it is NOT a given that Bush is an idiot, stupid, unethical, or whatever. If you've been paying any attention to the "people", you'll find that a solid majority of the country STILL approves of him. So by the Democrat's meter during the impeachment, everything is peachy, right? Or are you going to say that some things matter more now? That's what I thought.
So name a significant country that actually contradicts this trend. Then compare that to all the countries and times that confirm it.
You can argue anything if you so desire, but that doesn't mean that the facts bear it out. All sorts of countries work for less than the United States (not to mention most of the Western world), yet we continue to have low unemployment and overall rising standards of living. The same goes for many other enlightened countries.
You're even assuming that consumer purchase power is reduced. That's simply not the case and it's been demonstrated time and time again. What generally happens is that consumer's purchasing power rises on the aggregate, because goods and services get produced for less.
This is completely incoherant. Where are you getting this stuff from, off the back of a cereal box? How does a market failure result from continual innovation and increased efficiency? And wtf is slump supposed to mean in this context? How do you get from point A to point B? It does not follow.
Yes, you do get more leisure time. When you extropolate this pattern of increasing efficiency out across all people, it means that people on the whole can work much much less and recieve far more. In other words, before the days of tractors, fertilizers, combines, and such, mere existence demanded that the vast majority of society work on a farm. Now with all these advances in technology, that have necessarily obseleted those previous jobs, people are free to pursue other tasks, knowing that if they work a couple hours a day they will at least have basic sustenance. Although it may be true that people _raise_ their standards of living, and thus keep on working just as hard (if not harder), this is a matter of personal choice. Because people are basically rational, we can reasonably assume that they are happier working hard.
Some people stop making stuff and start making other stuff? Complete jibberish. Anyways, I am under the impression that you have a romantic view of previous centuries. If so you have little appreciation for history or economics.
The only shred of legitimacy that your argument has is that if innovation happens TOO rapidly and people get displaced TOO fast, then we could potentially have problems. But we are in no danger of that today. In fact, on the aggregate, the gains in efficiency that we have made in the past decade pale in comparison to others. What little oil workers there are would be READILY absorbed into today's economy. The vast majority of the people unemployed in this country (very low percentage by historical standards) today are unemployable and/or simply don't wish to work; it's not the jobs don't exist for the taking. In other words, if you're willing and able (as these most of these oil workers would be), you can find a decent job.
He shouldn't have to. Anyone that has ever studied economics knows that, as a general rule, efficiency is the path to wealth. If we had followed your sentiments for the past 200 years most of us would still be working on farms from sunrise to sunset. [Not to mention unemployment, GDP, public health, and other such issues]. Hell, compare employment figures between countries that try to protect jobs like that and those that don't. You'll find that countries that protect jobs the most tend to have the highest unemployment and the lower GDP per capita.
Take this example (ignoring the environmental concerns and such). We reduce our energy costs by 20% using this fission method. Sure, some workers lose their jobs in the short run, but the job markets are tight and they would be absorbed. Consumers get cheaper energy, meaning that you have to work less to get the same amount of energy. Furthermore, industry is then allowed to produce cheaper goods and services because they no longer have to pay for this waste, which transfers back into consumers pockets. When people have more money to spend on other things, guess what? They spend more. Meaning that there is more demand for OTHER goods and services that people would RATHER have.
The reason that fission energy is used to heat gas or boil water, which in turn is used to spin turbines for making electicity, is that fission energy comes mostly from kinetic energy.
For example,
n + U235 --> Heavy1 + Heavy2 + 2.4n + 215MeV
where n are neutrons, Heavy1 and Heavy2 are two
split parts of the U235 (Uranium 235) atom,
and 215MeV is the energy released.
Something like 90% of that is in the motion of
Heavy1 Heavy2 and the neutrons (i.e., 180MeV of
kinetic energy.) The kinetic energy of
Heavy1 and Heavy2 is deposited very quickly
in the surrounding fuel as heat. The neutrons take a little longer to slow down, but no one
knows a way to directly convert the energy in
fast neutrons into electricity.
As someone else has pointed out, if you're
doing nuclear fusion in a plasma,
as in
Deuterium + Helium 3 --> Helium 4 + proton
you can convert the energy directly into
electricity, because the fusion products are charged.
"There's on the order of 1.0e30-1.0e31 joules of energy stored in the Earth's rotation. That gives us around 30 billion terawatt-years.
"I don't think we're in danger of draining it soon."
Check this shit out:
The planet used an estimated 415.6 Billion BTUs in 2000. This translates to 121.8 trillion kilowatt-hours, whick boils down to 121800 terawatt-hours, or 13.9 terawatt-years.
Now, mind you, global energy-consumption is increasing at around 2.2% per year (ibid). So, the first year we'd only lose 0.015 seconds. No big deal.
To see how this would all work out in the longer run, I wrote a little script.
After 100 years we'd only have to adjust our clocks 5 seconds slower every year. In the year 2360 the Earth's rotation would exactly match that of Mars, with a 24 hour, 36 minute day. By 2540 the calendar would only have 364.25 days in it, and just 30 years later another day is lost.
In 2693 we've lost December entirely, and days are 26.2 hours long. By 2773 things have kicked into serious gear and we're down to a year of 182 days that are each 48 hours long.
Assuming that in the interveining 800 years we find a way to overcome the logarithmic problem of sucking the energy at a constant rate from a slowing source, we can take out the last of the rotational power in the Earth by the year 2812.
Pretty early on people would have to rewrite timing code that was based on the assumption of a constant number of days in a year and seconds in a day. And geosynchronous satellites would have to have ion drives constantly pushing them gently away from the earth into higher and higher orbits to match the slowing rotation.
Of course, the biggest problem here is clearly that we can't use DirectTV after 2812 because the geosynchronous satellites can't stay in non-orbit.
Kevin Fox
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Kevin Fox
So what do you think of the idea of dropping trash into a plasma jet and running the whole mess through an industrial-sized mass spectrometer? Every so often you empty out the barrel of Carbon, the barrel of Iron, the little bucket of Plutonium...along with the one hundred other bins and pipes for all the other elements.
I suspect it may have been an attempt at humour, rather than a troll. If it was a troll though, I say he gets some points for spelling "Johannesburg" correctly (research) :)
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"The situation is SA appears to me to be precisely the situation that lead to the first generation of Nuclear Power being a failure. It will be a political statement signalling the rise of a regional superpower"
I don't think the developments on PBMR in South Africa are politically motivated but economically motivated (Eskom is a large now privatised company).
South Africa has also already had a successful nuclear power plant for decades now (Koeberg, in the Cape), so I can't understand that we have much of a statement to make. Very few people also seem to remember that South Africa also had a nuclear program and successfully built and detonated a nuclear bomb (way back in the 70's already IIRC; the nuclear program was eventually dismantled). So I highly doubt that this is an attempt to make any sort of political statement, I don't think South Africa has anything much "to prove" in terms of nuclear technologies (unlike for example countries like India which are experimenting now with nuclear weapons, their political situation is entirely different).
Our president might not be the sharpest around at science (his degree is economics) so quite frankly I (and most everyone else) wishes he would refrain from attempting to make strong scientific statements, its embarrassing. But the President has absolutely nothing to do with the PBMR program, and believe it or not we do have some very good scientists and engineers here.
I think you should consider doing a little more research into the political and social climate and history of South Africa before making your conclusions, as it seems to me that by and large you've just mentally mapped the US political situation onto South Africa, assumed it is more or less the same, and made your deductions from that.
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Here's an interesting link discussing this type of reactor.
Much of the reason for the high cost of nuclear power is because of the safety mechanisms required by the public. The public does not trust nuclear power because its safety consists of multiplying an extremely small number (probability of meltdown) by an extremely large number (the consequences of a meltdown). The public prefers a known probability that coal miners be killed, that coal trains derail, that gas pipelines explode, and the radiation emitted by burning coal.
However, these new plants are much smaller (smaller danger from meltdown) and much obviously safer (e.g. no possibility of run-away), so they will produce a new level of trust in people.
Don't worry about disposal. The nuclear material exists in nature now and we manage to live with it. There's no reason why we can't put it back with a level of safety equal to background radiation.
-russ
Don't piss off The Angry Economist
Do we really want to cause the death of an industry for the sake of cheap electricity?
Yes, we do.
The millions of people who work in electricity plants, where nuclear reactors are used responsibly by the government, will beg to differ on that one.
A society that protects its workers at the expense of its consumers will forever be a poor society.
-russ
Don't piss off The Angry Economist
Most of the power in an H-bomb IS due to fusion
Wrong. Check out the Federation of American Scientists, who have a remarkably accurate FAQ on the matter. Check out this link for details.
Or, for those who are goatse.cx averse, I'll just reprint a snippet of the FAQ here: The 5 Mt Redwing Tewa test (20 July 1956 GMT, Bikini Atoll) had a fission fraction of 85%.
The next claim of yours--namely, "It is naive of anyone to believe that nuclear weapons design is common knowledge"--is just as absurd. The principles behind nuclear-weapons design are straightforward and are taught in college classrooms to undergraduates. In the height of the cold war, nuclear-weapons design was published in the open literature. One physicist might write a paper detailing the particular physical properties of compounds exposed to extremely high radiation flux and whatnot, comparable to those found in the heart of a star--a perfectly acceptable scientific article, but when you say "heart of a star" I hear "in a nuclear weapon undergoing supercriticality".
The Manhattan Project was chaired by General Leslie Groves of the Army Air Corps/USAF, but all the principals involved were scientists. Have you ever tried to get a scientist to keep something a secret? They can't. They're genetically incapable of secrecy. It's right there in their DNA sequence, somewhere in that giant double-helix, that says, "if it's cool and it furthers our understanding of the cosmos, I've GOT to tell people about it!"
As far back as the early 1980s, the magazine The Progressive was sued by the United States Government to prevent them from publishing extremely detailed specifications and schematics of nuclear weapons. The DOE only withdrew the lawsuit after it became clear that to get an injunction against The Progressive, they'd have to declassify even more documents and put even more weapons-design material into the public record.
In the Manhattan Project days, it was VERY difficult to obtain large amount (mere pounds) of weapons grade U-235 and plutonium.
No it wasn't. Uranium is a very common element. You can refine it out of granite, for crying out loud. The difficulty has never been in getting fast-fissile material; the difficulty has been in separating it out. Yes, centrifuging it all out is tremendously power-intensive, but if you want the bang, you gotta pay the buck.
The main reason most nations cannot produce nuclear weapons (specifically hydrogen-based nuclear weapons) is because they don't know how to arrange the materials
Nope. The engineering behind it is well-known. The difficulty comes in getting refined fissile material--world governments keep an excruciatingly close eye on stockpiles of refined fissile material (save in the former USSR, which is why it's a source of such concern to arms-proliferation wonks), and building facilities to refine raw material into enriched fissile material is considered extremely destabilizing to regional peace, and as such, is strongly discouraged.
I used to believe this too. Of course, like many things, the truth is a little more complicated. When I tried this line on a physicist friend of mine (who used to work for the AECL), she sat me down and smacked me around. :)
While the heavy water moderator is required to initiate the reaction (the rods are initially less than critical mass), once started, the rods end up enriching themselves, and may be able to sustain a reaction on their own.
Also, even if the reaction stops, the rods may generate enough heat to melt anyways. This is because a good fraction of the heat generated in the plant is by the decay of fission products. You can't stop the decay no matter what you do.
Of course, this is probably incredibly unlikely. But that just means you have to roll the dice more often. :)
Cool eh?
Jason Pollockgreat. So now you have diluted radioactive elements. Which would be great appart from the fact that in order to be viable as a storage option, you'd have to dump alot of stuff into the volcano. When it erupts, the resulting radioactive magma (was that a joke I didn't get?) lands ontop of everything.
great! so now the whole region is covered in radioactive rocks. This has helped the situation how?
I'd been given the impression that one of the main reasons that reprocessing was abandoned was that the process could be used in the creation of isotopes suitable for nuclear weapons. As I recall, in the 70's we signed some treaties basically renouncing the process and creating an international ban on the process in the name of nuclear non-proliferation. I'd never heard that saftey was the main reason that it was dropped, but rather international politics. Not sure how recent the info was, though. . . Anybody got a more recent answer on why the US has pulled back from reporssesing, or is it really just the saftey issue?
"Sweet creeping zombie Jesus!"
Aren't there some serious problems with leakage of these containers into the groundwater table? I seem to remember hearing something akin to that...
I'm obviously no physics guy (otherwise I most likely wouldn't be asking this question), but couldn't spend fuel be dumped in an active volcano where it would melt down in liquid-hot mag-ma (sorry, had to say it) and diffuse the radioactivity?
just my blog and pix
Uranium is a by product of gold mining in South Africa and the price of gold has been lagging for some time now. The Forbes 500 companies with the highest growth in profits are the oil companies (reported last week) and venture capital for energy grew an average of 115%/year from 1995 thru 2000 it only makes sense for Dutch Boers to team up with the internationally respected black African politicians of South Africa to overcome the barriers, both technical and political, between their mining infrastructure and the already growing world market for uranium.
Seastead this.
Hmmm ... what you are describing sounds more like a U-bomb than an H-bomb. Doing this from memory:
...)
U-bombs were tested in the late 60s. Basically, the idea was to wrap a H-bomb with uranium. The A-bomb trigger would go off initiating an H-bomb explosion which in turn would induce fission in the outer uranium layer for an increased yield. It was a very messy weapon and didn't have a whole lot of strategic value as such. I think the one test killed a bunch of fisherman in a Japanese boat called the "Lucky Dragon" (I forget the original Japanese name) from fallout who were trolling a bit too close to the test site. However this might be more than a little bit mixed up.
It has been a while since I've thought about the history of above-grounds weapons testing and if you are relying on Slashdot for a nuclear physics education you are just plain silly. As a Ph.D. in plasma physics, it is distressing to see the number of scientific dubious assertions that get moderated up (it is as though science here is decided through committee and not experiment).
In any case, because there are many variants of atomic weapons means I don't have a great deal of faith in the previous poster. Depending on the details of the trigger and fusion fuel you can get all sorts of weapons (optimized for explosive yield, optimized for EMP, optimized for neutron yield, optimized for fallout or lack thereof,
A blanket statement that all fusion bombs are fission powered is a bit misleading.
Furthermore, if I recall correctly nuclear proliferation treaties were entered into which effectively arrested development of U-bomb type weapons. Your level of cynicism will dictate whether that means anything to you.
Kevin
"the same explosive fuel that downed the hindenburg"
The Hindenburg was not downed by the Hydrogen. The Hindenburg went down because the the fabric "skin" over the metal frame had been painted with a mixture containing powerdered aluminum. It was the first time a blimp had been painted with the substance, and before that the extreme flammability of the stuff was unknown. When the ship dropped its mooring lines, a sparc from the static it picked up from storm clouds arced somewhere on blimp, and the aluminum in the paint caught fire. It burned at several thousand degrees, and the entire skin of the blimp went with it. The heat collapsed the frame, and blew up the hydrogen tanks inside.
The whole thing was discovered by the Germans soon after the explosion, who covered it up fearing that shifting blame from helium to the aluminum paint would make Nazi scientists look bad. It was later discovered by a NASA hydrogen expert who saw that the giant flames and burning skin were inconsistent with hydrogen explosions. He found remnants of the blimp's skin and tests confirmed his theory.
Just a little eye opener...
I agree. To speak with athority on power generation you should get a degree in Nuclear Engineering, work in a plant, and know what you are talking about.
The only reason Chernobyl went up and Three Mile Island did not is luck. Both reactors were designed using inadequate computing power. Chernobyl went critical because there was a region of positive feedback in the operation cycle that was not uncovered using the two dimensional simulation techniques used in both the USSR and the US at the time.
BzzzT! Wrong, this had nothing to do with inadequate computer simulations. US reactors, at least, were tested out with models, then prototypes and pilot stations. These are the kinds of things men have been using instead of computers for all of human history but the last 40 years or so.
Both accidents were caused by operators overcoming automated saftey features. At Chernobyl, the operators were testing safety features at low reactor power levels and outside electricity turned off. They were not supposed to do that. At TMI, operators failed to believe their insturments and turned off systems that would have shut the plant down safely. There the similarities end.
Chernobyl suffered a steam explosion and uncotrolled release because of poor design goals. It was a dual purpose reactor providing both electricity and plutonium. The core was water cooled and graphite moderated, the graphite serving to promote plutonium ingrowth. It was also an easy access reactor, with nothing between it and the world but heavy concrete blocks. When the operators got everything just wrong and core power jumped from 0 to 1000% in a thousanth of a second or so, they were doomed. The heat released immediatly precluded control rod insertion, leaving the core overpowered and uncontrollable. It then got hot enough to make a steam and hydrogen explosion that blew those concrete blocks off with such force that they destroyed the refueling crane above. Without further barriers to release, the contents of the core were free to kill operators and make a mess for miles around. Nasty, but it won't happen at a US plant because we don't have easy access reactors. We have contained reactors desinged only to make power.
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While the attempted environmental extortion is admirable, the world will not reward people like this. Reality is that Joe San-Diego did not want a powerplant in his back yard yesterday. Today, he has to pay an absorbident amount for an artificially limited commodity.
Poor Joe. He's going to suffer rolling blackouts and all that. Burgalars will rob him while his alarm is off. His food will rot when the fridge is turned off. His house will mold and mildew while his AC is off, his air indoors will be worse than that outside and his health will suffer. His children will get asthma and he'll have to pay for expensive medicine and hospital trips. His trafic lights will be unreliable and his car rides will take longer and be more dangerous. One day, after an automobile accident at a broken traffic light, his hospital might loose power and all the OR gadgets will sputter and fail.
Oh well, that's too bad for Joe.
Friends don't help friends install M$ junk.
Chernobyl was operated at high power levels (normal operation) and then shut down for about eight hours while engineers mucked with the console, then brought back up to critical condition. The basic problem is that nuclear reactors are not like cars. When you shut 'em off, they don't just lie dormant until you switch them back on again.
When you operate a reactor, one of the fission products decays (half-life eight hours) into Xe-135, which absorbs neutrons strongly. That has the same effect as inserting a bit of control rod into the reactor, and as the reactor comes up to equilibrium levels of Xe, you have to pull out bits of actual control rod in order to compensate. The equilibrium level of Xe 135 in the core is determined by the balance between production (which depends on your average power level over the last eight hours) and destruction (which depends on your power level now) of the Xe.
When you turn off the reactor, you stop destroying the Xenon. It builds up in the reactor core, effectively shutting down the reactor by greater and greater margin until, about eight hours later, it reaches a peak level and begins to decay again.
The operators on the day of the accident found that they had to pull large amounts of extra rod out of the reactor core (because of the Xe-135, though they didn't pause to think about it). When they brought the reactor critical, the Xe-135 was quickly destroyed by the neutrons in the core, removing the extra damping effect and making the reaction run away.
Even then, "SCRAM trips" (emergency shutoff safeguards) in the console would have saved the day except that they had almost all been disabled to test a single particular one.
The real problem with nuclear power isn't the "normal" waste disposal problem. It's the incredible, abject, deep stupidity of the bottom 1% of nuclear plant workers. You can engineer around physics, toxicity, and radiation -- but you can't engineer around foolish people. I was finally convinced of this truism by the insanely stupid people in Japan, who made their own critical assembly out of dissolved uranium (by doubling the uranium batch size for faster processing) -- other examples may be found in the nuclear plant lore here in the U.S.
Surprisingly, dams are not clean energy sources. Many of them produce a large amount of carbon dioxide http://www.newscientist.com/nl/0603/stink.html, so they wouldn't help with global warming.
where do you think the carbon dioxyde we exhale comes from?
From our lungs, not our stomachs. (You said exhale, not belch.)
OTOH, flatulent cows are actually a significant source of methane, another greenhouse gas...
--
And big box stores wiped out mom'n'pop stores, themselves wiped out by internet stores, now, can I interest you in some stock in a nice internet business?
/. terms, it means that MS software is much better than anything else. Flamebait? No. For the general office worker, it may be a good thing for MS to take over everything. But we can think of many situations where the loss of software craftsmanship is a bad, bad thing.
/.ers are squeezed middle income, rich as long as we have our high-paid software jobs, just a few paychecks out of living out of individual transportation modules.
Economics becomes paradoxically inefficient as markets mature, because the profit incentive becomes the entire driving force. So why do anything when you can get pure profit?
My stepdad had a toy and hobby store. It got wiped out by toys r us. Now the big box stores and chains are having big time problems - is it playco I just saw having a liquidation sale? How about etoys.com? The net result is much fewer hobby shops, with the loss of artisan advice giving. Remember when you were little and built things? Now everything is just manufactured and toys magically appear - even build-it toys are leaving less to the imagination - check out a lego set lately? So the inefficiency that economics doesn't address is that of good workmanship - there is a strong incentive away from it, in fact. Of course, in many circumstances, mass production is a good thing - even Ferrari has come into the 20th century for making engine parts. But there needs to be a balance of craftsmanship, and that is what is lost. In
And the other thing placing too much faith in market economics is, you wind up with a bifurcated economy - the rich get richer, the poor have children. Most of us
Oracle and unix guy.
When an element goes through a nuclear reaction, it becomes a different element. So it isn't like your putting the same stuff back down there.
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The sun isn't going to bake water into hydogen and oxygen, it's going to turn it into water vapor. And attomic power dosn't come from the sun at all
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The material is already 'critical' otherwise they wouldn't even work. This was clearly stated in the article, so I can only conclude you didn't read it at all.
Anyway, all that would happen if some guy tried to 'open it up' is that he would severely burn himself, and spill really hot beads all over the place, it wouldn't cause Hiroshima style explosion. And you would need to use dynamite in order to get the case open (or some similar explosive)
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No, that's not my pic that's just a link to the main site (the slashdot sig cuts me off). The URLs keep changing on p-r.c, but the actual JPG of me is here
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or maybe the server's dedicated fission reactor just melt down..
--
Escher was the first MC and Giger invented the HR department.
Not only will we be able to get power so cheap that we can kiss rolling blackouts produced by centralized power generation goodbye, but we can also worry about what happens when someone want's to "reverse engineer" the thing by opening up the box and "checking out" the hardware, in the name of information being free. Man, I sure wouldn't want to be living within 100 miles of someone who thinks it wise to tinker with a small nuclear reactor.
And think about the chain reaction that would be caused by one "going off." If anyone else in the area had one, the resulting EMP would probably fry the control electronics and cause other devices to go "critical," thereby setting them off too. What a blast that would be (no pun intended).
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BEFORE USE:
1. Remove cranium from anal cavity
2. Take a physics course or two
U-238 is fissionable. It is not fissile, so it is not used for fuel in reactors, except to be bred into Pu-239. Neutrons at the energies produced by fission reactions cannot induce fission in U-238. At that energy, neutrons either don't interact at all, or are captured, leading to beta decay. Neutrons from fusion do have enough energy to induce fission, though. When you look at the reactions, you see that a few grams of deuterium-tritium mixture can produce enough high-energy neutrons to induce fission in several hundred grams of U-238. I can't comment on the exact numbers (not a nuclear engineer), but the given figures definitely fit in order-of-magnitude estimates.
This is why H-bomb schematics always show a cylinder of U-238, with a rod of U-238 down the middle, and the intervening space full of deuterium and tritium, with a complete fission bomb at one end. I think there's usually a beryllium casing outside the uranium cylinder, but I'm not positive.
It is possible to create a bomb which derives almost all its energy from fusion, but such weapons are heavy and large for their yield. They have almost the same design as described above, but the U-238 jacket is replaced with tungsten or lead. One mostly-fusion device, the Tsar Bomba, derived 97% of its yield from fusion. It was intended, however, to have a U-238 jacket, to produce an even higher yield.
Most of this info was taken from the Nuclear Weapons FAQ, section 1.5. Here's one link, I'm sure Google can find more if you want.
Bugrit! Millenium hand and shrimp!
I thought "green" meant getting power from crystals or butterflies or some shit.
green means different things to different people. To me it means first that the cost of every product should reflect not only how much money it took the producer to produce it, but also the cost of cleaning up the mess that third parties are left with as a result of both its consumption and its production. Second, green means that we should not party at the expense of our grandchildren. Taken together, what I want to say simply is that green means fair. But then again, I am a green-red colorblind.
-- look, cheese ahoy!
The idiot in the Whitehouse is certainly not someone I would trust to ensure that safety standards were enforced.
From the reasons you mentionned and the way the two parties have positioned themselves in the last two decades, I suspect that reviving nuclear power in the US is something that no Republican president can pull off. It would just cause too much fallout ( political, not nuclear). Only a Democrat running on a green message will carry enough trust to overcome the fears of the public.
PS. The Idiot is a diversion, mind the crooks in the background.
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Overall, the political, technical and economic feasibility of disposal of all types of waste and of decommissioning plants has yet to be proven anywhere in the world. A responsible policy would appear to be to carry out investigations into these processes so that there is confidence that when these processes are required, they are technically proven and the resources to carry them out are available.
Waste is the deal breaker. I am sure that it is possible to find a feasible solution to this problem. But it will require heavy governmental subsidy from countries richer than South Africa. It will take time, and it probably won't be cost efficient unless the cost of dirty electricity factors in the whole gamut of environmental externalities including global warming.
Next month Dick "The Nanny" Cheney will come out with recommendations for a new US energy policy, that will probably include nuclear power. This could be a good opportunity to put funds into waste disposal research that could turn results in a decade. My suspicion, however, is that this is not what we are going to see. The proposal will most likely suggest building reactors here and now, and giving subsidies to energy utilities that will be used mostly to disburse dividends. Given the likelihood that the plan will generate extreme political outrage, I strongly suspect that its real purpose is to draw fire, paint environamentalists as extremists, and finally "compromise" on good old coal and gas subsidies. What a pity! But then, I may be wrong -- we will know that next month.
-- look, cheese ahoy!
A previous poster noted that France has not had a nuclear problem. The reason behind this is quite simple: standardization.
Several decades ago, France was searching for power sources. Lacking local natural resources needed to power conventional plants, they considered nuclear power to be their best bet.
Unlike most of the rest of the world, France realized that safety came from using standarized equipment. They came up with an initial reactor design, and stayed with it. Everyone working on nuclear plants in France is trained on the same equipment; countless engineers could easily transfer from one plant to another without missing a beat.
This is not the case in many other countries. Most of the world's reactors outside of France all have their own custom designs, largely in part to utilize later discoveries. Should someone design a home reactor, the fact that it is a well analyzed design should bring some comfort (hopefully with interlocks!). Nuclear technology has gotten a lot safer; but the early accidents have scared the public away, possibly forever.
Hydrogen was not what downed the Hindenburg. This is a popular misconception. The real problem was that the damn thing had a reflective coating of powdered aluminum, so that the hydrogen wouldn't get too warm from sunlight or something... esentially, it was coated with Thermite! All it took was one spark, and POOF!
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
Nope, it's the neutrons. There's a lot of energy output too -- thought not as much as you might think; the fusion reaction is actually a little less energetic than the fission reaction, but it scales in ways the fission reaction can't. And it makes all those damn neutrons, which aren't really what you want, but send them into a block of U238 and you get a very, very, very large boom for your buck.
Brackets contain world's first nanosig, highly magnified:[.]
My figure comes from an interview with Ted Taylor in a photographic essay book At Work in the Fields of the Bomb which I can't seem to find right now so I can't tell you who the author was. Since Ted Taylor built the thing, I tend to think of that as a firmer figure than anything quoted in the linked site.
It is entirely believable that the DC was scaleable, as an adjustment in the boosting would have the effect of radically changing the yield. Taylor was somewhat reticent in the interview (he was close-mouthed, for example, about the concept of levitation which is revealed in full in Richard Rhodes' Dark Sun: The Making of the Hydrogen Bomb). So there may have been this extra capability he couldn't reveal because of his security clearance, but the 500 ton figure is in the midrange of the "variable yield" figure.
Brackets contain world's first nanosig, highly magnified:[.]
Bombs like this need to be very heavily boosted with Tritium, which is both expensive and has a short half-life so they require relatively frequent maintenance. IIRC a guy named Ted Taylor is responsible for designing a lot of these "miniaturized" designs. They are an offshoot of the H-bomb/ICBM programs, and rely on some of the same technology as H-bombs.
Brackets contain world's first nanosig, highly magnified:[.]
Yes, it would. It would be another animal entirely, though; the neutrons created by the fusion reaction have to do something. So when you replace the tamper in an H-bomb with something that won't fission, you get what is called a neutron bomb.
I'm sure you've heard of them.
Brackets contain world's first nanosig, highly magnified:[.]
No it isn't. It's approximately 10% fission trigger, 10% fusion reaction, 80% induced fission in otherwise unfissionable depleted uranium thanks to the neutrons from the fusion. This is one of the most important lies that was exposed by Howard Morland when he exposed the "secret" of the H-bomb in The Progressive.
In fact, because of the way its major fission reaction is triggered the H-bomb is dirtier than an "equivalent" mass of A-bombs. The fallout is more complex, the isotopes are more exotic, and it is just plain something you don't want to be around when it goes off. Or 1,000 miles downwind from, either.
Brackets contain world's first nanosig, highly magnified:[.]
Evacuating Philadelphia is probably possible in a short time, Manhattan is next to impossible. The idea of building any plant of that type next to the tri-state area is pretty whacky.
The Chernobyl fallout pretty much trashed cities 200 miles away. The real issue is the way the wind happens to be blowing at the time.
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Only Nixon could go to China
I agree, I think that the only way that Nuclear power can be revived in any form is under a President who is not so openly disdainful of science and environmentalists.
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There was more than one factor. However the comfortable myth that the explosion was caused by operator error is just that - a self serving myth. The operator's actions caused the meltdown however those actions were within the operating proceedures of the plant.
The cause of the explosion was that the reactor had an unknown region of positive feedback. That in turn was due to the simulations of the reactor being pretty rudimentary. At the time the standard approach was to simulate in 2D and then extrapolate using experimental data to 3D.
It's the incredible, abject, deep stupidity of the bottom 1% of nuclear plant workers.
Placing the blame on the shift crew is a good way to pretend that the problems could not occur in the US. That is why the US and British nuclear lobbies were pushing the 'operator error' theory long before there was any evidence that might support it.
I was finally convinced of this truism by the insanely stupid people in Japan, who made their own critical assembly out of dissolved uranium (by doubling the uranium batch size for faster processing)
The Japanese event was caused by management who ordered the workers to mix the stuff by hand in buckets rather than use the expensive machinery installed for that exact purpose. It was the plant management that decided that using the machinery took too long.
It appears that it was the workers who had the bright idea of mixing the stuff in double quantities.
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You remember doing 3D simulations? Or you remember being fed the propaganda?
Most reactors in use today were designed in the 60s or late 70s. The computing power to do 3D simulations simply did not exist, either in the USSR or the US.
All accidents look ridiculous after the fact.
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I doubt that big oil is too unhappy with the contribution from Mr Nader. I think that the Anwar oil field should be named after him.
While most politicians are slaves to the contributors most do actually take some time to come up with a policy that is marginally defensible. Bush appears to believe that all scientific evidence of harmful environmental effects is produced by liberal crypto-communists who are members of a giant conspiracy against capitalism.
I don't think that even US politicians would knowingly permit an unsafe nuclear plant to be built. Bush has made it plain that he only wants to hear scientific advice that supports his policies.
That is exactly the type of politics that rightly got nuclear power derailed in the first place. The Canadians built safe designs. But both the US and the USSR built unsafe designs. Challenging the nuclear establishment in either country meant the end of your career. They even destroyed Oppenheimer.
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Well perhaps you don't know but lots of US researchers including MIT have been working on pebble bed.
The magazine article is pretty far off base. I was not commenting on it because I didn't think it merited it. Fissile Uranium is the most highly controlled mineral arround. The idea that folk are suddenly going to be able to buy it by the sack full in Home Depot is plain stupid. Pebble bed reactors are certainly cheaper than light water but they are nowhere near as small and simple as the article makes out.
The other piece of data that had been raised in the discussion but you appear to be ignorant of is that Bush has been advocating building nuclear plants.
Only thing is that Bush is not pushing for the intrinsically safe designs. He wants to build more light water stations.
I am not particularly keen on SA building nuclear stations either. Their government is also headed by a scientific ignoramous who has convinced himself that HIV does not cause AIDS after listening to a discredited quack [apparently there is also a dose of wishful thinking since the President would prefer not to pay for AIDS drugs even at the low prices the sucessful patent suit make possible]. On top of that, the super powers built intrinsically faulty designs because Nuclear Power became part of what we nuclear physicists call a dick size contest. The US built nuclear stations to show it could tame the destructive force of the atom, the design and construction schedules were dictated by propaganda needs. The USSR naturally had to follow suit and built even faster and with even more carelessness.
The situation is SA appears to me to be precisely the situation that lead to the first generation of Nuclear Power being a failure. It will be a political statement signalling the rise of a regional superpower.
The economics of the design almost certainly depend on selling copies of the design in the West. To assert that the US has no influence is to miss the point. The US will likely fund the scheme before it is finished.
There are governments that might be capable of handling nuclear power responsibly. If the Blair government said new nuclear power was necessary that would be pretty credible. However given that their exisiting nuclear capacity costs three times as much to run as the coal fired and the fact that the UK has 400 years of coal reserves the chance of the UK being forced to go nuclear is vanishingly small.
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The sad fact of nuclear power is that it is probably possible to do the job safely but it is easier to say that safety is number one priority than to make it number one priority.
Unfortunately there are many with the attitude that everyone who thinks there might be a problem with Nuclear power must be a tree hugger. If the people making the decisions and regulating Nuclear Power have that attitude we are likely to have a repeat of the 1960s - plants built in locations they should never have been using recycled military designs that were completely inapropriate.
The folk telling the President to build nuclear stations are probably the same ones who are claiming that Nuclear Missile Defense is viable.
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How do you know that nuclear power is efficient? The thing that you have neglected to mention is that, right now, there is no long-term solution to the nuclear waste problem. The only reason that nuclear power is a viable choice today is that the cost of disposal has not been factored in. Some of the isotopes have half lifes on the order of 10^6 years...
This is great! Not only do you get power for your house, but as a by-product, you can use the waste heat to heat your pool, and the Cerenkov radiation will light it at night!
Err.. How did you work this one out? It makes no sense at all.
How can any single nuclear reaction (by which I mean just one fission or fusion) _EVER_ release over a _kilojoule_ of energy? I think you have make a mistake between KeV (kiloelectronvolts) and KJ (kilojoules)... There's a seriously big difference!
Be nice to people on the way up. You will meet them again on your way down!
I see a number of technologies in development that could easily give pebble beds a run for their money. The waste products of nuclear reactions, and massive strides in technology neccesary to make them more feasible on a large scale make fission a somewhat unremarkable, and unlikely choice for the powerplant of the future.
A number of power companies and research groups, under a Department of Energy initiative, are testing Solar Two -- the world's most technically advanced solar energy power plant -- in the California desert. It works like this: A 300-foot-high central receiver captures energy reflected by more than 1,900 surrounding mirrors and uses it to heat molten salt, which is, in turn, stored until it is needed to generate electricity. Solar Two, which was connected to California's grid in 1996, can itself power 10,000 homes, and alarger-scale commercial plant based on it could handle as many as 200,000.
Southern California Edison is already testing microturbines: small, clean-burning natural-gas power plants that cost a relatively inexpensive $25,000 to $200,000 to build, depending on size. Microturbines could be plopped in the middle of a city to serve a few thousand customers in the immediate area.
In whales, waves are being used to generate power for a small town. The generators are little more than small turbines and cement tubes, and were built at a very low cost.
In comparison to all of these already implemented technologies, pebble beds, which have been batted around and dismissed since the 80s, don't seem like reasonable options.
My Karma is so good, I'm the Dalai Lama...or something.
As you admit, water, solar and tidal (plus geothermal which you omit) are all partially viable. Why not diversify? Say, 10%-15% for each of the 4 (I know for a fact solar could easily handle that much, I'm not as familiar with the other 3). That brings us up to 40%-60%. Then let nuclear do the rest reducing as the other four get more efficient (or when fusion starts working).
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324006
Spent fuel is not the only problem. The reactor casing and shielding become radioactive as a result of exposure to neutron bombardment. Not as bad as the fuel, but not the sort of thing you'd want in the county dump, either.
Incidentally, except in some exotic cases, this is also a problem for controlled fusion reactions, which generate a lot of energetic neutrons.
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Of the 103 operating nuclear power plants in the US, 2 are in California. There used to be 3, but Rancho Seco was shut down in 1989, and hasn't put out a single kilowatt-hour of electricity since. So, no, not all of your nuclear power plants are on-line. Have a nice day.
Notice I said "strip mining." A pound of uranium will last years, while a pound of oil, coal, natural gas, etc. may last you a half-hour, depending on what you do with it. One or two mines in the entire US would provide all the fuel we'd need. And they'd be small/slow enough to to be way more environment-friendly than your average coal mine.
"Most people freak at the thought of meltdowns and at the radioactive waste produced. We're already used to accepting the smog produced by Coal & oil plants, but radioactive disasters seem so utterly scary to the States, possibly as a result of years of Global Thermo Nuclear War fear?"
Nah, the big problem are the people (*cough* Californians *cough*) that want NO new power plants, no matter how the electricity is produced. :)
The worst nuclear accident in the US was an almost-meltdown at Three Mile Island near Harrisburg, PA, and that was how many decades ago? Compare that to the various natural gas explosions that occur around the country. Boiling liquid-vapor explosion, anyone?
What was the worst accident in France, where they get 80%+ of their electricity from fission? And they're in the forefront of technology in civillian fission (though they're lagging behind the US in nuclear propulsion, as with the rest of the world).
Whatever you have to say about the spent uranium from the plants, it is still the most environmentally friendly power generation around. Not only are there no emissions involved by defintion, but there's also no off-shore drilling, no tanker spills, no strip mining, no pipelines, no explosive railray cars, no high-pressure vessels (aside from the boilers themselves)... hell, even windmills and solar arrays require lots of open land, often at the cost of the native animal and plant life.
"but it will not be solve the thrird world and california's energy problems."
Actually, California's power problems would be solved by re-activating the nuclear plants that California environmental lobbies have shut down. As the lights flicker and diesel backup generators kick in, there are perfectly good nuclear plants just waiting to be used out there.
"Fission power is what fuels the hydrogen bomb"
No. Fusion is what fuels the hydrogen bomb. While it is true that, right now, the only known way to get an exothermic fusion reaction is with the heat and energy created by fission, fission is not a requirement for fusion. Look at the sun.
"we are proposing that we put fission reactors in everyone's home? "
Just because you have a little radioacive isotopes in your home doesn't mean that it's the right kind of isotope (or even element) to make a bomb, that there's enough to make a bomb, or that you will be able to use it make the isotopes to make a bomb.
And consider how many homes in the northeast have 1000's of gallons of heating oil (and the explosive fumes involved) underneath their yards.
"possibly by doping it with Iron, which can cause nuclear meltdown if done correctly, because Fe- + H "
I could be wrong, but you still seem to be confusing fission with fusion. No hydrogen involved in fission. At best, you might claim that there's "hydrogen" involved, but that's only because that's what emitted alpha particles are (technically speaking).
Meltdowns only happen if your core is large enough to get hot enough to melt the fuel (and just about anything else), and your cooling system and your control system fails. This is generally only applicable to large-scale/naval power plants, because they have (relatively) large amounts of fuel.. If I have a fission reactor in my back yard about the size of my air conditioning unit, I'd have to be pretty damned talented to get it to melt down.
"Also, there are social implications - unemployment and the death of an industry. Do we really want to cause the death of an industry for the sake of cheap electricity? "
If the alternative is people freezing in the middle of winter, or dying of heat stroke in the summer because they can't afford their power bills, then HELL YES!
"where nuclear reactors are used responsibly by the government, will beg to differ on that one. "
Actually, this would be a boom to the nuclear power industry. Imagine if nuclear reactors were as numerous as air conditioners.
As for other power generation, they'll need new jobs. Just like what happened to the ice deliverymen when the refrigerator was developed. And all those whalers that lost their jobs when people switched to fossil fuels and electric lights. If bettering society as a whole means a few people lose their jobs, so be it. Majority rules.
"We must not embrace new technologies solely because they are new, but rather because they improve our quality of life."
You don't think that having to pay a power bill isn't an improvement in the quality of life? Do you work for SoCalEd or something?
"or that you will be able to use it make the isotopes to make a bomb."
I meant "or you'll be able to use the reacter as a breeder to make weapons-grade isotopes."
"At best, you might claim that there's "hydrogen" involved, but that's only because that's what emitted alpha particles are (technically speaking). "
I typed "hydrogen," but I was really thinking "helium." H... He... what's the difference? A proton? :)
The sun is a mass of incandescent gas
A gigantic nuclear furnace
Where hydrogen is built into helium
At a temperature of millions of degrees
Yo ho, it's hot, the sun is not
A place where we could live
But here on Earth there'd be no life
Without the light it gives
We need its light
We need its heat
We need its energy
Without the sun, without a doubt
There'd be no you and me
The sun is a mass of incandescent gas
A gigantic nuclear furnace
Where hydrogen is built into helium
At a temperature of millions of degrees
The sun is hot
It is so hot that everything on it is a gas: iron, copper, aluminum, and many others.
The sun is large
If the sun were hollow, a million Earths could fit inside. And yet, the sun is only a middle-sized star.
The sun is far away
About 93 million miles away, and that's why it looks so small.
And even when it's out of sight
The sun shines night and day
The sun gives heat
The sun gives light
The sunlight that we see
The sunlight comes from our own sun's
Atomic energy
Scientists have found that the sun is a huge atom-smashing machine. The heat and light of the sun come from the nuclear reactions of hydrogen, carbon, nitrogen, and helium.*
The sun is a mass of incandescent gas
A gigantic nuclear furnace
Where hydrogen is built into helium
At a temperature of millions of degrees
Trivial as it may seem, energy gained by tidal power is, erg for erg, slowing down the rotation of the Earth. True right now the results are inconsequential, but if massive projects were undertaken to supply 30% of the Earth's onging power needs with tidal forces, over the long run it could have an impact, and it's not exactly like we have a way to repair the damage by speeding up the Earth's rotation...
At least clean fission only eats up matter which, though not a renewable resource either, is constantly being replenished on the order of tons a day from micrometeorites.
Kevin Fox
--
Kevin Fox
I am in need of enlightenment.
e -of-a-walnut mind takes this to mean, there are other possibilities. Does anyone know of any research being done on this? (Of course, with the fear of anything nuclear that seems to prevail in modern society, I wouldn't be surprised if a project like this would find difficulty getting funding.)
;)
Nuclear Fission releases incredibly large amounts of energy, even when it is a controlled fission such as that in a nuclear reactor. If I understand correctly, nuclear fusion is capable of releasing as much as if not more energy. But like the topic says, IANANP.
Now, perhaps I read too much science fiction, but surely there must be a better way of harnessing this energy than using it to boil water (in the case of current nuclear power stations) or heat up helium (in the case of this article) to turn a turbine to create electricity. It seems to me that a LOT of energy would be lost in the transfer from heat to mechanical to electrical energy.
The article mentions that "The early designers and builders minimized the risk of their projects by combining the new nuclear fission--based heaters with the well-proven closed-cycle steam engines." So, my Isaac-Asimov-reading-lets-build-a-reactor-the-siz
I dunno, but it seems like an awful lot of energy is being wasted in the current reactors, including these new PBMRs mentioned in the article
And I have to admit, I wouldn't mind having a personal sized one to power my home for a couple of years (decades? centuries??...depending on the amount of fuel). Oh well...perhaps I was just born a few hundred years too early.
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
Nuclear fission in your basement? SAY! That is a clever idea. This is what old sub commanders think about when they retire. QUOTE: Eskom, a large public utility in South Africa, has taken a serious look at nuclear fission technology and is committed to the pre commercial development of an alternative type of machine called the pebble bed modular reactor (PBMR)..... Of course, the early adopters of such a technology will not be average homeowners. A likely initial customer might be the owner of an isolated tropical island or a remote mountain with a spectacular view. (AN IMPORTANT MARKET I'M SURE, MH) The machines could be designed as black boxes containing a decade or more of fuel and needing only a cooling supply and a place to put the output power. They would not spoil the view with an exhaust stack and could be buried to muffle all noise. (ON THE OTHER HAND, WHEN FORGOTTEN AND REDISCOVERED 200 YEARS LATER, THEY MIGHT POISON ALL LOCAL DRINKING WATER ... BUT NEVER MIND, NEVER MIND, AT LEAST THOSE ANNOYING SMOKE STACKS WON'T BOTHER THE ISLAND'S OWNER...)
The possibility of home-size cousins of the PBMR coming to a neighborhood might raise concerns. (WHAT ME WORRY?) What if an external explosion, as from a ruptured natural gas main, shattered the tough shield surrounding the PBMR and scattered the pebbles? (HOW COULD THAT HAPPEN, IN OUR MODERN SOCIETY?) In such a scenario, the radioactive material would remain contained within the pebbles. (OH DR. SCIENCE, I'M SO GLAD THE PUBLIC IS SAFE!) Of course, the pebbles would be hot, in terms of both temperature and radioactivity. (WELL... THAT DOES SOUND MILDLY WORRYING.... LITTLE HOT RADIOACTIVE PEBBLES ALL OVER THE NEIGHBORHOOD... SHOULD I WORRY?) Residents would need to be evacuated until professionals collected all the pebbles, but then they could return safely to their homes. (OH GOOD.. FOR A MOMENT I WAS WORRIED, BUT SINCE THERE WOULD BE PROFESSIONAL PEBBLE COLLECTORS INVOLVED, I'M SURE EVERYTHING WILL BE OK!!!)
END QUOTE
And there is not a single mention of nuclear waste, fission by products, or waste disposal issues!
2-3% of it will always be "in the transportation tube" rolling down local railways, interstates, and highways. And if one of these trains derails? Or truck jack-knifes?
Then the heavily-armoured barrels get their paint scuffed.
I don't trust nuclear waste barrels to last a hundred thousand years, but I do trust them to survive anything short of a point-blank strike from heavy artillery.
If you *do* fire heavy artillery at point-blank range into a nuclear waste barrel, you'll get a clould of glass shrapnel - the safest transportable form of nuclear waste puts waste oxides into glass, where they stay (glass is quite durable and resistant to chemical attack). Scrape up the first foot of soil for a quarter of a mile around, put that in barrels, and sent it to the waste dump along with everything else. No additional contamination.
In summary, I don't think that accidents during transport are a concern. I'd be more worried about deliberate theft, and the risk of that can be made no worse than it already is with waste stored at power plants.
Also, storing waste at the plants is not a viable long-term solution, as they aren't in earthquake-free regions isolated from the water table. One good disaster, and *all* of the plant's waste goes into the environment.
They don't have to be buried. Extract the plutonium and use it up in a reactor designed for it. Put the other stuff in the business end of a nuclear accelerator, or park it on the edge of a fission reactor, and make it break down sooner than by waiting for natural decay.
The problem with any scheme that involves chemical reprocessing - which used to be widespread - is that you get a lot of minor mishaps occuring, which exposes workers and the nearby environment to small amounts of Really Nasty Stuff (tm).
If I understand correctly, worker health liabilities were why plutonium reprocessing plants were abandoned, but in general, it's just plain safer to seal up the waste in very sturdy containers and drop them in the continental sheild.
As far as transmuting the waste is concerned, there are problems. If you stick waste next to a large neutron source (like a reactor), it will be transmuted. Continuously. This has the good effect of transmuting long-lived radioactive isotopes into shorter-lived ones, and the bad effect of transmuting non-radioactive decay products into radioactive isotopes. This won't magically make the waste non-radioactive (well, after a few centuries of this, it might all end up as the four stable lead isotopes, but don't hold your breath).
In summary, while burying the waste in mine shafts is an imperfect solution, it's one of the best ones that we currently have. We can always dig it up later if we find a really good way to dispose of it.
The big problem for nuclear power is that the Nuclear power industry has lied and lied and lied. It is no wonder that the public don't trust nuclear power, they would be morons if they did.
The only reason Chernobyl went up and Three Mile Island did not is luck. Both reactors were designed using inadequate computing power. Chernobyl went critical because there was a region of positive feedback in the operation cycle that was not uncovered using the two dimensional simulation techniques used in both the USSR and the US at the time.
If the west was so smart in its nuclear power strategy Three Mile Island would never have been choosen as a site with Manhattan right next door.
The problem today is that having lied about the costs, the safety and the military use of byproducts the civil nuclear industry is going to have a hard time being trusted even if it is proposing an entirely different technology.
Pebble bed and Heavy Water designs are both intrinsically safe technologies that will 'fail safe' in case of failure. Unfortunately the nuclear industry claimed that the intrinsically unstable and dangerous AGR and light water designs were 'fail safe'.
The backers of pebble bed have a point. However having been lied to the public is entirely rational in not trusting the experts again. The idiot in the Whitehouse is certainly not someone I would trust to ensure that safety standards were enforced. The administration has reneged on pledges to not drill off the coast of Florida and to implement C02 emissions caps, arsenic in drinking water is OK. And that is the crew to be trusted to regulate nuclear power?
We may need to start using Nuclear Power in the future, however I think we can wait another four years for a President who is not in the pocket of the energy companies before we let that genie out of the bottle again.
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Yeah, you know me!
Do people seem to forget that there is entropy in this universe? All production of electricity causes some form of energy loss. Thus the obvious problem of efficiency.
Nuclear power is very efficient, and does not pollute much. Sure, the pollutants are highly toxic, but there is a smaller proportion of it, than to coal power (as an example). I'd rather have nuclear than coal. Coal pollutes the atmosphere and is far worse than nuclear power, as is oil, and other fossil-fuel based power sources.
Water power is clean but all of the prime locations have been used... thus further plants would be on less effective/efficient sites and end up being very expensive ways of ruining the surrounding ecosystem.
Solar and wind power are not constant enough yet to be relied upon as a sole source of electricity. In addition, these technologies cannot be used universally, some locations will see a benefit while most will not be economical.
Tidal power is effective, but cannot be implemented everywhere (and I mean every oceanside town here). The local topography needs to be just right for tidal power to be economical.
Fusion power is not economical yet either, although there are projects in the works.
So that leaves us with dams and nuclear power (fission) as our clean energy sources...
The problem with nuclear power is that the public is uneducated about the safeness of the power production process. In the US and Europe, nuclear power is extremely safe because it is highly regulated. Safety measures are considered, then will be increased beyond the engineers' original specifications. Chernobyl was as bad as it was because Russia couldn't afford to build a safe plant... they followed the motto "good enough for government work."
This is for all the folks who told you fusion powers the hydrogen bomb:
The H-bomb uses a fission trigger which supplies about 10% of its energy output. The prompt gamma rays from this blast are used to compress and trigger the secondary stage; this must occur before the mechanical blast rips the secondary apart.
The secondary contains a stick of fission fuel surrounded by fusion fuel surrounded by a thick, depleted Uranium tamper. When the assembly is compressed the stick of fission fuel fissions, providing neutrons which...
Finally, the incredibly huge mass of neutrons generated by the fusion reaction induce fission in the depleted Uranium tamper, yielding about 80% of the bomb's energy. Now we have an explosion. And 90% of the energy comes from fission, not fusion.
The mantra about H-bombs being "clean" is just one of the many lies told by the nuclear industry to make itself look more useful than it really is. Richard Rhodes' books The Making of the Atomic Bomb and Dark Sun: The Making of the Hydrogen Bomb have many more details about how the current situation came about.
Brackets contain world's first nanosig, highly magnified:[.]