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Toshiba Pushes Safe, Small Nuclear Reactor Design
core plexus writes "This article describes a proposal from a Japanese corporation that wants to thrust the Interior Alaska community of Galena into international limelight by donating a new, unconventional electricity-generating plant that would light and heat the Yukon River village pollution-free for 30 years. There's a catch, of course. It's a nuclear reactor. Not a huge, Three Mile Island-type power plant but a new generation of small nuclear reactor about the size of a big spruce tree. Designers say the technology is safe, simple and cheap enough to replace diesel-fired generators as the primary energy source for villages across rural Alaska."
I don't have much faith in them. I had a toshiba laptop once, I kept it on for a week and it melted. :(
I have over 70 freaks, do you?
Gives new meaning to the term "Northern Lights".
52 Weeks, 52 Religions with John Hummel
Alaskan homes need a lot of heating.
And if something goes badly wrong, is anyone really going to trek through the snow and ice to check things out? Just kidding.
While the Japanese nuclear "industry" is one of the worst in the world in terms of safety, it's impressive that reactors are this small, and maybe this will eventually come to be the standard for electricity generation in places where the other fossil-friendly alternative - namely hydroelectric power - is not an option.
Ceci n'est pas une signature
So's fire (unless you count dragons).
If all this should have a reason, we would be the last to know.
Reactors such as these, if they are indeed safe for residential use, would go a long way towards preventing another regional blackout (like the one we enjoyed several months ago in the US). Decentralizing the power grid has always been a challenge, and this could make it simple - if it is indeed safe.
Never underestimate the potential of Human stupidity. -Heinlein
Pitr bought out Toshiba, and started up his plutonium-powered UPS device again?
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
"The word 'nuclear' makes me nervous," said Randy Virgin of the Alaska Center for the Environment. "But we've long seen the problems with diesel, and I'm pretty excited about the prospect of a clean source of energy," he said. "It sounds very promising, but I'd approach it with extreme skepticism."
There is soooo much less polution from nuclear reactors given the probability of worst case scenarios versus the diesel they are currently using. Why are we still burning fossel fuels!@!#@#!@!#
They arent in a location very suitable for wind/solar either, so nuclear seems like the best non-renewable solution.
Such a backwards society we live in, when technology is available and safe, and we delay in implementation.
[I can picture a world without war, without hate. I can picture us attacking that world, because they'd never expect it]
In addition, if you bury the waste in the desert, in containers that don't corrode, where's the harm?
This is my sig. There are many like it but this one is mine.
They live in harsh conditions and don't romanticize about it. Something like this would make life easier...wonder how many gallons of fuel oil a village goes through a year.
Blar.
This was already done in remote parts of Soviet Russia. The problem is that the devices went without supervision and were subsequently plundered by scrap metal thieves. See http://archives.tcm.ie/breakingnews/2001/05/24/sto ry13735.asp for an article about the problem.
Are we supposed to take this article seriously? Randy Virgin? Either his parents didn't like him, or this is some kinda spoof!
Don't you see? Nukular stuff is like guns, it's EE-VILE!
Like guns, the uranium will leap out and attack people. Don't give me that "safety" crap. I don't want to be disturbed by facts...
You don't get it. This is Japan's way of getting rid of their radioactive waste. Notice they didn't offer to build this test plant in rural, remote Japan.
If all this should have a reason, we would be the last to know.
I have to say after reading the article, the reactor design does sound very safe. Here is a quick rundown of reactor advancement...
-Big hunk of uranium in a pool of water*. Water heats but is under pressure so it can't boil. The water (contaminated and radioactive) is then piped through fresh water (in sealed pipes) from a lake or river transferring heat so the fresh water will boil and turn turbines. Neutron absorbing control rods are raised or lowered into the big hunk of uranium to control the reaction. Problems can occour with pipes corroding and releasing contaminated water*, control rods can jam, leaks in the coolant water* can cause a loss of coolant leading to an overheated reactor.
-Little pellets of uranium in a pool of water*. Same principle as above, only there are no control rods. As the pellets heat up, the expand, increasing the distance between the pelets. This is much safer because there are no control rods to jam. Loss of coolant can still be a problem, but easily solved by simply moving the pellets further apart.
-And now, this reactor.. a Big Rod of Uranium is immersed in a pool of water*. The rod of uranium is sub-critical so it can't sustain a (large) heat producing reaction on its own. A sleve made of neutron reflecting material (google for nuclear bomb neutron reflector) slowly makes its way along the BRoU over the reactors 30-year lifespan. Only the uranium surrounded by the sleve can react. If the sleve moves too fast, then the reactors lifespan is simply shorted - it will never produce more heat than can be made via the reflector. If it moves too slow, the reactor simply produces less heat. Overall a very good design. If I were to have a reactor in my backyard, I definately would choose this style.
I've gotta hand it to the toshiba people.. I wouldn't have thought of this... pretty cool.
*Note: Water may not be water. Water is often used because of its high specific heat, but many other liquids have been used as coolant. In the toshiba reactor, liquid sodium is spec'd because its non-corrosive. A big plus in a maintenance-free environment.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
WOW! You must be some sort of comedic genius!
Remember the 'Foundation' series? This sounds like it came straight out of there. Minature Atomic Reactors. Of course Asimov assumed that 'Atomic' was the brave new future and was envisaging reactors the size of a walnut.
Mielipiteet omiani - Opinions personal, facts suspect.
There's actually some sound reasoning behind this. By putting such a nuclear reactor in a small village, they will be able to provide power to the entire surrounding area instead of just a fraction. If this was placed in a large city, you would have to somehow partition the power grid into small pieces. Not impossible, but not as easy as simply replacing the diesel generators at this small village.
They may also be trying to market this specifically as a solution for those small, remote sites. Imagine how much diesel fuel would be burned over the course of thirty years -- then realize that a small amount of nuclear fuel could do the same job. Yes, yes, I know that nuclear waste will last much longer than thirty years. The advantage, however, is that nuclear waste is much more manageable and, if taken care of properly, is not as damaging to the environment.
Cheers,
-a
I think placing spent fuel into subduction zones on the sea floor, so that they get recycled would be a good idea.
I drank what? -- Socrates
A major Japaneese corporation donates a high tech, ultraclean nuclear reactor to remote Alaskan village. The plant goes online, and everyone is happy until....
One day, all contact with the village is lost. A crack team of physicist/commandos are sent in, headed by Jean-Claude Van Damme or Vin Dielel (the Governator's too busy). What they find will SHOCK and HORRIFY the world, horribly disfigured villagers, mutant killer walruses (they came inland, they're mutants!) and a conspiracy going further than they could have imagined.
There is a reason for everything. Sometimes that reason just sucks.
So is this one of those situations where limelight = green glow?
Wouldn't they just find a way to buy a brand new core? That way they get the 90 day warranty.
Randy Virgin sounds like a villian in an Austin Powers film
Pick two.
'Nuclear' doesn't actually enter into it; it's just one locus of possibilities within the 'Safe/Cheap/Small' domain.
-Hentai [in vita non pacem est]
But my hometown lies 15 miles from Waste Control Services, and the plant sits right on top of the Ogalalla Aquifer from which the entire region pumps its water. The "corrosion proof containers" are metal barrels buried in a cement-lined pit. Along with the radioactive material are "non-corrosive" substances like old batteries and various forms of chemical, petroleum and medical waste. To top all this off, some "stabilized" napalm has been added to the mix as garnish.
Taken separately, these things are not harmful. Properly encased by well-trained robots in impervious material, these things are not harmful. But... packaged by overworked, underpaid, undereducated laborers in the cheapest material available with security checks run by firms hired out by the company to be yes-men, dumped together en masse in a cement pit, I'd say these things have the possibility for a big ka-boom.
So... to answer your question -- avoid West Texas at all costs.
IAALS.
I googled for "bomb neutron deflector"... should I just ignore the black helecopters that just landed outside my house?
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Yes, what to do with the spent fuel is a problem, but is the cost of storing the degrading material higher than what we pump into the air each year? Let's face it Solar and wind are not there yet. (Although if your looking to make a worth while investment in your home, consider adding solar cells if you live anywhere outside of the pacific northwest, my father did and uses it to heat water and some applices and its paid for itself in 3 years. Me I still rent, so someday)
I wish people would get over their nuclear phobias and NIMBY additudes because something needs to be done, and adding more gas turbines and coal plants are not the best solution.
"The problem with socialism is eventually you run out of other people's money" - Thatcher.
Except that its in a hardened, sealed concrete enclosure, meaning there would be no way to access the material short of digging it up, and then using a jackhammer and doing some welding to get inside the facility. On top of this you'd have to shut the reactor down, so you'd have an entire village that knows something is up. Add to that that this is NON-WEAPONS grade Uranium, and there is much less motivation. If a bad guy wanted just plane radioactive material there are far far far easier ways to get a hold of it, than these reactors.
That's one drum per 7.5 years per village of 700 people. And perhaps you'd check how much it costs to deal with one drum of high-level waste (i.e. store it for the 50000 or so years it will take to become safe).
it's impressive that reactors are this small
Accoring to the headline, the reactors are about the size of a big spruce tree.
Why is this impressive? US subs and aircraft carriers are powered by nuke plants which are in the same rough size, if not smaller as a spruce (which, according to this pages stats are roughly in the range of 30-60 ft tall and 20-30 ft wide). And the boat and ship nuke plants have been around for many years, too.
What would be impressive, though, is if they CAN indeed run trouble free for 30 years.
Dogma - "let's just say we'd like to avoid any empirical entanglements."
TMI is a great advert for nuclear power! Everything that could go wrong went wrong, and the operators made mistakes. The core melted, but no-one was killed or injured. The same can not be said about coal mining disasters, Bhopal (a chemical plant in India which exploded) or oil rig accidents. If you have a social conscience you will support nuclear power. Other energy industries regularly kill its employees and members of the public. Alaska suffered terrible environmental damage when Exxon Valdez crashed. To prevent that happening again we need to embrace clean new clear power!
"Have no fear for Atomic Energy" - Bob Marley in Redemption Song
$20 million for 10 Mw? - what they need to make is a smaller one - I would pay 100K for a 100 kW reactor to put in my back yard. Oh, wait, I live in Chapel Hill, and the greenies would much rather burn tons of coal and wood. Never mind.
It's got a design where it needs mechanical energy to stay critical, so it can't break down and stay critical, and over-production won't increase the production rate. It doesn't irradiate the parts that could need to be serviced or any liquids. It contains the fuel needed for 30 years, which isn't that much in terms of a big plant (121 days supply for a normal-sized plant). Won't need to be changed for 30 years, and it'll be pretty obvious if someone tries to steal the core.
The only problem I can see with it (aside from public perception) is that it involves a shaft dug into permafrost. I'd be somewhat worried that a wet fall followed by a sudden cold spell could lead to the shaft getting crushed.
Of course, it will be hard to sell people on, despite the fact that this is probably a much safer thing to have in your back yard than a gas main. I'd like one in my back yard, except for the fact that it's not cost-effective to run, unless you're in the middle of nowhere in a place without sunlight.
The typical response with most nuclear devices is "not in my backyard". However, the technology used in modern reactors is exactly the type I DO want. And yes, they can put it in my backyard (heck, they can put it on my property for free, in exchange for free hydrogen, electricty, and heat). I hadn't considered Alaska as a retirement location, but where do I sign up?
Can You Say Linux? I Knew That You Could.
Yeah, but SL-1 had control rods. With the control rods sticking all the time, the fault was found to be that the crew had to manually pull out a control rod to fix the control rod drive mechanism when it stuck. Well, some guy ended up pulling the control rod out too much, and the core went prompt critical (same thing that happened in the 1999 Japan accident when their mixture of uranium achieved critical mass). The coolant flashed to steam and shot the control rod out with the guy pinned to the ceiling. Because of SL-1, the navy changed all their reactor designs so that they could be shut down even with the most critical rod fully withdrawn, meaning that prompt criticality with one rod could never occur again. Obviously, Toshiba's reactor won't have the same problem since they're not even going to have control rods nor will they have any reactor coolant pumps. I'd be more worried about their new idea of using the reflector to control the power, not having any pumps, or using liquid sodium as the primary coolant.
Oh wait, wait........imagine a beowulf cluster....oh fuck it.
Buy Steampunk Clothing Online!
And never forget about incidental pollution not related to burning... like the occasional oil spill.
It's been thought of. Google for "nuclear waste subduction". The problem is that subduction is a long, slow process, punctuated by violent activities like earthquakes and volcanoes.
You could accumulate a lot of waste in a given area that was slowly being pulled under, and then an volcano blows it all back up again. Or an earthquake cracks the seals and you've got contaminated groundwater or whatever.
The problems seem solvable with careful choice of site(s). There are places where the odds of such things are quite small. Pick someplace offshore, for one thing.
In reality, you'd have a greater risk of an accident in transporting the waste there than in any major incident happening.
PHEM - party like it's 1997-2003!
I used to work at a US reactor in IT. At the time I was both amazed and stunned by the 1960's erz technology in use in the plant.
Because it had to be "certified" and documented, the cost was outrageous. Each section of pipe had to come from a certified company built by a certified company and using materials (ore, etc) from a certified place, all documented of course. Makes you feel better about the construction, but costs a lot and requires lots of maintenance.
At the time I saw some specs for a new, simple design to be used in Asia and submitted to the NRC. It used less people, more gravity fed pumps and flows, and should have lowered the cost of plants from billions to hundreds or even tens of millions.
Nothing came of it and it was a larger scale than this, but it was a good idea. Nuclear has a place when built well and conservatively, which it seems this design is.
Frontline, a great PBS documentary series, had a show on this, called Nuclear Reaction. Highly recommended.
you could nick 2 of them....
I love it when people don't read the article. I assume this small hand grenade is one of the "bunker busting" variety? If you read the article, you'd discover that due to the design of the reactor, it is virtually impossible to make it go critical. Even if you found a way (neutron enhancement ray?), the damn thing is buried underground, where most of the shock of an explosion would be absorbed by the surrounding dirt.
I read the internet for the articles.
90% of the problem with nuclear power is the tremendous ignorance of people regarding it.
Dangerous nuclear waste hangs around for a couple of weeks. The 50,000 year stuff is all low-level stuff. People living in Colorado will get more radiation mowing their yards.
We're constantly bombarded with radiation NOW. Everywhere. In the food we eat, in the water we drink, in the air we breathe.
A major nuclear disaster would be, well, like Chernobyl. Really bad in the surrounding area, Nothing at all a hundred miles away.
But Chernobyl does bring out the biggest danger with nuclear power. idiot bureaucrats running the reactors.
You can tell a great deal about the character of a man by observing those who hate him.
So... to answer your question -- avoid West Texas at all costs.
Sound advice, regardless of the environment.
Perfect logic. He's not talking about C02. He's talking about the gaseous uranium compounds released by burning coal. It's about six million tons a year if I remember right. That's six million tons of uranium, not C02.
You can tell a great deal about the character of a man by observing those who hate him.
On the other hand, plutonium, also used as a reactor fuel is 100% fissionable. The reactor fuel is the same material used in bombs. Plutonium is also highly toxic. I believe the lethal dose for human consumption is something on the order of a microgram.
The design of the reactor itself seems safe, but the proponents are ignoring the fact that after its 30 year lifespan, what is left over is going to remain radioactive for the next 10,000 years. After putting up some yellow police tape around the area, who is to say that the reactor building itself won't corrode and decay in the next hundred or two hundred years, and then the secondary nuclear waste is exposed to ground water?
In a worst case scenario with a nuclear powerplant, we're talking about, what, 50,000 years until it's safe again?
Nothing like that. Heck, people still live in Hiroshima and Nagasaki, which were subjected to far worse than what a nuclear powerplant would do. (Although it's possible that cancer incidence is still slightly higher there -- lots less than the equivalent risk from, say, smoking tobacco.)
Chernobyl was just about the worst case scenario for a nuclear plant -- and that was a really stupid design with a positive void coefficient and a graphite moderator -- which caught fire when the cooling water boiled away. Chernobyl still isn't the best place to hang out for very long, but there are other places that can be naturally more dangerous (such as downhill from a lake that occasionally bubbles toxic gases, such as the one that wiped out a village in Africa some years ago, or the valleys in geologically active regions that can collect lethal levels of sulfide gases and kill the occasional unwary hiker, and so on.)
Oh, and as for "Nuklear Power plant has a jet that flies into it.", in the US and Canada at least (and probably most other places), the result is a flattened jet and maybe a few scratches and scorch marks on the (many feet thick, reinforced, densified) concrete of the containment building.
-- Alastair
Back feeding lines is an issue, but not as big as you might think. In nearly all cases your house is not the only one isolated, thus when you start backfeeding lines, all your neighbors think they have full grid power and start to use it, but since you don't have an unlimited supply of power, the breakers (and fuses) on your generators trip. Thus you are forced to correct the problem before you can use your own backup. That said, back feeding does happen, and it is dangerious. Dangerious enough that line workers short known dead lines before touching them so they are not a good path.
Second, in many states (Minnesota where I live for sure) the power utility must hook up any residentialy co-generation plant and use all power supplied. The amount they pay you is regulated somehow, but I'm not sure of the details. (You won't make enough to pay for a gasoline generator, but for wind, hydro or solar uses it can break even)
Of course a lot of coal is produced by "topping". Which is where they take the top of a mountain off and dump it in the nearest "ravine" (IE: water way) No water pollution 'cause the creek/stream/river doesn't exist anymore.
If you think nuclear waste will need to be kept around for hundreds of thousands of years, check into actinide burners.
It looks like we may be able to break down the seriously radioactive stuff from nuclear fuel and turn it into the stuff that is only slightly radioactive (think dangerous for about 100 years.)
So we reprocess the spent fuel, which we aren't doing now. That's 90% of your mass right there that you extract and put back into the reaction.
Now take that 10% and extract the 2% plutonium that is in it and use that in one of the nuclear plant designs that can run on plutonium/uranium mix.
Now with the 8% that is left, process it in an actinide burner and you have a small amount of material that needs only to be kept for 100 years before it isn't really very radiactive. In practice, the closer you get to the 100 year mark the less dangerous it becomes.
Natural != (nontoxic || beneficial)
'Cause gas is US$3.35 a gallon so the plant becomes cost effective much sooner.
He means that the amount of radioactive waste produced by a nuclear plant is less than the amount of radioactive waste produced by a coal-fired plant of equivalent power output.
And yes, coal is normally not considered radioactive. But it does contain traces of radioactive material, both in the coal itself and as waste rock from the mining process that isn't entirely separated. Not very much, of course -- but it takes thousands and thousands of tons of coal to produce the same power as a few pounds of uranium.
Of course, all radioactive waste eventually decays. We haven't even touched on the other stuff in coal ash that's highly toxic (like arsenic) that never decays.
I'll happily store the waste from the nuclear generated power I use in my backyard if you'll store the ash from the coal generated power you use in yours.
-- Alastair
Plutonium is not as chemically toxic as some think. I know many people carrying multiple body burdens. See http://www.aps.org/apsnews/articles/11351.html for more info on others with high body burdens. Again, I would suck down a bottle of pu spiked water but it is not an immediate death sentence like taking cyanide.
I agree that much more radiation is released from coal fired plants than nuclear. It has been shown in McBride, J.P., R. E. Moore, J. P. Witherspoon, and R. E. Blanco, Science 202, 1045 (1978) that you receive a higher radiation dose by living next to a coal-fired plant that you do living next to a nuclear reactor.
Discussions like this usually begin with, "What is the best way to deliver x (well, okay, n) megawatts to this community? But as Amory Lovins and others have pointed out, the starting point has to be determining how much energy is really needed. The least-cost approach would look at efficiency improvements first, because anything that reduces demand at a cost of less than $2000 per KW is a better buy than this power plant.
Again, RTFA. The steam loop is secondary. The primary loop is liquid sodium and located below ground. You'd have to be one fancy driver to even hit the secondary loop, considering that it's in the middle of a concrete building, and getting to the primary loop would be nigh impossible. Furthermore, security around nuclear power plants tends to be pretty tight. When's the last time you heard of any one, anywhere in the world, getting an unauthorized pickup near a reactor building, or even onto a campus?
The Spoon
Updated 6/28/2011
And of course, the problem with the storage and disposal of Nuclear waste is that people still have it in their minds that it might actually be useful at some point (read: be able to make bombs out of it)
If you were to break up the waste, mix it with glass, and bury the resultant big frigging block of glass in the desert, you're pretty much golden (or at least that's what the discovery channel told me). You just can't dig it up later and use it to kill people with.
- ------- There are ten kinds of people in the world. Those who understand binary, and those who... Huh?
The only commonality between the reactor you mention and the one in the article is that they are both nuclear reactors. The toshiba reactor uses a subcritical mass of uranium, so that it is inherently stable. A neutron reflector is used to cause a sustaining reaction. The reflector is sized specifically to create the temperature that the reactor is designed for (plus a margin in case you need to run a little hot) it is specifically designed not to be able to go supercritical and create a self sustaining reaction. There are no control rods because none are needed. Technology has advance alot in the last 4 decades. I wouldnt want to drive a car from 1961 either because they were also designed inherently unsafely.
Lesse. THe power core is sealed in a steel shell 30" in diameter and 6 feet long.
At about 95 pounds per cubic foot, this power cell alone would weigh just shy of 3/4 ton.
Then add in the fact that the cell is welded to the end of a 70 foot long steel tube filled with liquid sodium - with no way to access the core except for:
a) Lifting the 76 foot rod out of the ground via crane (required disconnecting everything first of course - probably some noticable downtime)
or b) digging a tunnel down about 70-80 feet, busting through the reinforced concrete outer shell, the steel inner shell, somehow not dying from the 900+ degree heat and radiation, cutting the red-hot power cell off the end of the steel tube (risk spilling high pressure liquid sodium!), then hauling the 3/4 ton cell back up to the surface.
Both a and b require that this operation be done without anyone getting suspicious.
Somehow I don't think some guy is just going to waltz in and pilfer the core.
The only time it would be vulnerable would be during routine maintenance - once every 30 years - and then it would probably be a fairly secure location similar to any other nuke plant refuling.
=Smidge=
It's called the Law of Mass Action, and it has nothing to do with politics or leaping out at anybody or talking funny or being a Luddite. It's a physical law that simply says that the more reactants you place in a vessel, the more product you're going to get. This applies to guns and it applies to nuclear waste. The more guns in circulation, the more people die. The more radioactive material in circulation, the more people get irradiated. You might as well pump cyanide gas into everybody's house and then pass a law telling them not to breathe for all the good developing "safe" guns or "safe" reactors is going to do.
Hic iacet Arthurus, rex quondam rexque futurus.
(I used to operate a nuclear reactor, so I have some idea what I'm talking about here).
I'm a bit skeptical about the reflector mechanism: certainly, it makes sense to use a neutron reflector to modulate reactor output. But the business about "if the sleeve moves too fast, then the reactor's lifespan is simply shorted" doesn't make any sense to me.
The lifetime of most reactors is determined by the buildup of "poisons" (neutron-absorbing waste products) in the fuel, which is why reprocessing plants work so well: unlike a coal plant, a nuclear plant generally doesn't get more than a small fraction of the available energy out of its fuel, so you can chemically repair the fuel and use it again.
But the buildup of poisons in the fuel is dependent on the total amount of energy released so far. So moving the reflector too fast should either (A) produce more heat or (B) not affect the lifetime of the core very much. Toshiba seems to be claiming (not-A) and (not-B), which doesn't jive (prima facie) with reactor physics.
Small reactors in subs and ships can provide enough clean power to run small cities.
(I think this is a GOOD idea as long as they don't use Russian reactors...)
As I remember, they brought two aircraft carriers to New York to provide power after 9-11. I don't remember if they used them or not but they brought them in to do it. Two aircraft carriers could have provided enough electricity to handle a LOT of the city.
That's pretty amazing and damn, that's a LOT of power. Beats the hell out of burning fossil fuels and polluting the air we ALL breathe and posioning the land, sea and air, making plants, people and wildlife sick, some of it dying off forever and god knows what genetic damage is being done.
In 1,000 years, provided anyone is left alive, "people" are going to be so badly mutated that they won't be recognizable as humans...
I would like to see the total abandonment of fossil fuels in favor of non polluting technologies, solar being the prefered (where feasable) because it is silent and has minimal impact on the enviroment, provided that they are manufactured and installed with the enviroment in mind.
The reactors, handled PROPERLY and responsibly are a damn sight better choice than fossil fuels..
I did better than read about Hiroshima. I talked with a lady who lived there. She was born there and lived there her entire twenty-one years. That's right, Hiroshima is a thriving port city with about half a million people living in it.
Most of what messed up Western Europe was the hysteria whipped up by the media. Please show me the mass cases of sterility, mutation, birth defects, etc. rampaging across that continent right now.
The fact is, the radioactivity in the atmosphere of Western Europe matched that of western Montanan for a few weeks after the disaster. That's it. End of story.
What causes fear is ignorant people like you who don't have a clue what you are talking about.
You can tell a great deal about the character of a man by observing those who hate him.
MIT has been working on an even safer method for years: Pebble Bed reactors. The idea is: seal the uranium in bocci-ball sized graphite balls (uranium reaction won't get hot enough to melt the graphite balls). to stop the reaction roll the balls away from each other. when the fuel is spent, the U is sealed in graphite.
http://web.mit.edu/pebble-bed/
Also, whenever people invoke Three MIle Island, I'm always obliged to point out that ZERO nuclear waste was released during the accident. It was all completely contained. Most people think it was like Chernobyl, but the fact is: the safety standards worked for 3-mile.
https://www.accountkiller.com/removal-requested
For each element, there is a small list of stable isotopes. If a nucleus becomes unstable for whatever reason, it attempts to return to a stable configuration. There are several ways this can happen, including radioactive decay and fission.
The nucleus of any atom is held together by binding energy, and tries to fly apart due to electric repulsion between the protons. The binding energy per nucleon has a broad maximum around 8 MeV and nuclear mass between 50 - 75. Unstable, heavier nuclei may undergo fission into smaller nuclei with higher binding energy. The difference is released as heat, which we use to generate power.
The electric repulsion increases as the square of the number of protons in a nucleus, so more neutrons per proton are needed for heavier elements to maintain stability; however, there is a limit, and elements beyond Bismuth (83) are naturally unstable. These nuclei undergo radioactive decay, which occurs in two types: alpha and beta.
Unstable, heavy nuclei emit alpha particles, which are identical to Helium nuclei -- two protons, two neutrons. This radiation reduces the atomic mass by roughly four, eventually bringing the element to a stable nucleon count. Unstable nuclei also can undergo beta decay, converting a neutron into a proton and a high-energy electron, which is emitted. The amount of time needed for half of a sample of material to radioactively decay is called the half-life.
For fission, there are only three isotopes with a long-enough radioactive half-life to be stored and transported, and which are fissionable by neutrons of all energies: Uranium-233, Uranium-235, and Plutonium-239. U-233 isn't natural, and is created by inducing Thorium-232 to undergo beta decay by adding a neutron. U-235 occurs in small but extractable quantities in natural Uranium ore. Pu-239 is created by U-238 neutron capture and beta decay.
Alpha- and beta decay cause ionization in matter with which they come in contact by knocking off outer-shell electrons. Alpha radiation for Pu-239, the most energetic alpha decayer in a reactor at 5.1 MeV, has a range of only 3.6 cm in air, after which it is low-enough energy to absorb two electrons from the air and become a Helium atom which can't ionize. Uranium reactors, like the Toshiba model, have even smaller alpha ranges. Nuclear reactors are not at risk for leaking alpha radiation.
Beta radiation consists of electrons, which are much more likely to scatter when they ionize, so there isn't a specific ionization range for beta radiation. On the other hand, the highest energy beta radiation from fission reactions is on the order of 3 MeV, and can be stopped by half a centimeter of concrete. There is no possibility of beta radiation escaping nuclear reactors.
Gamma radiation, produced by neutron capture reactions, drops off exponentially as it is absorbed, so it can be reduced to background levels by a manageable thickness of iron or lead shielding. Normally, this occurs immediately surrounding the reactor vessel itself. If the vessel develops a leak or the shielding fails, nuclear plants have additional concrete shielding and containment procedures. In the unlikely event that everything fails, exposure to reactor gamma radiation is comparable to going to a doctor for X-rays -- not something you'd want for prolonged periods, but not going to injure you before you evacuate. In the case of the Toshiba reactor, which is 60 feet underground, there is no possibility of gamma leakage because the ground acts as shielding.
This post expresses my opinion, not that of my employer. And yes, IAAL.
Why has nobody thought of this before? Would this reall work?
Big article on this in Scientific American many years ago, in opposition to the Nevada waste site. Again the greatest danger is in transportation, but once entombed there is really no way for the material to harm anyone. You put a core dirlling ship in the ocean and dril a hole 2-3 kilometers into the ocean floor. You then drop barrels of waste into the hole separated by a few meters of the sediment. Even if the conatiners were to breach the material would at most disperse a few meters into the surrounding sediment over thousands of years. There is no worry of ground water contamination or even human contaimination once entombed, and eventually the material ends up melted into the mantle.
But, there is the threat of an accident during transportation, which is a worry for any nuclear waste disposal method.
Are you a reporter? Nicely sensationalized piece here. You even got moderated up to 5; good job (but woefully overrated)!
The SL-1 accident occurred almost completely due to operator error and lack of knowledge/respect of the system being "operated" (and I use that term loosely).
When you climb up on top of a reactor, override operating mechanisms (however crude they were) and pull a rod out by hand, bad things tend to happen. What happened in that case was the rapid increase in reactivity caused a localized steam explosion that ejected the rod completely (giving the operator a ride to the roof in the process). Needless to say, it was a very stupid move made in an age where operating procedures were loose and effective safety mechanisms were rare.
Yeah, it was a bad accident. The only nuclear accident in U.S. history directly causing deaths. But it's silly to even begin to suggest that history can repeat itself, because there is virtually no similarity between the modern reactor being discussed and the SL-1 reactor.
--CP
FUD ALERT! Check your facts please...Google is my friend. MOD THE PARENT DOWN!
.01 seconds, causing the plate-type fule to melt. The molten fuel interacted with the water in the vessel, producing an explosive formation of steam that caused the water above the core to rise with such force that when it hit the lid of the pressure vessel, the vessel itself rose 3m in the air before dropping back down (Derived from DOE and US Army records)"
http://www.radiationworks.com/sl1reactor.htm
"A small, 3MW experimental BWR called SL-1 (Stationary Low-Power Plant No. 1) in Idaho was destroyed on January 3, 1961, when a control rod was removed manually."
snip
"A careful examination of the remains of the core and the vessel concluded that the control rod was manually withdrawn by about 50cm (40cm would have been enough to make the reactor critical), largely increasing the reactivity. The resulting power surge caused the reactor power to reach 20,000MW in about
1) 3MW not 200kW - Makes a difference
2) It did "melt down" - effectivly anyway
3) It did contain water (presurized or not I dunno)
4) It was caused by human error
5) It was probably a lot larger fuel block
Silly FUD's, google will always win!
Apple free since 1990!
> Ram the pipes coming out of the ground with a pickup. Let blow some steam out. Drop grenade.
Listen to grenade go *BOOM*. Realize that one needs to read up on nuclear reactors.
You really don't know the first thing about how these things work, do you? What would you possibly hope to accomplish by dropping a grenade into the secondary coolant loop, other than stopping power output, which would be accomplished by the truck hitting the pipes?
Virg
Of course the article isn't very clear, but I don't really see either not-A or not-B claimed as such.
It seems to me that the reflector is a ring moving down the rod, and at any time you have completely clean fuel at the head end of the ring and progressively more poisoned fuel toward the tail.
If the reflector moves too fast, the fuel within will be proportionally less poisoned, and though the output may be greater, it still won't be more than when the reflector started out on 100% clean fuel.
The reflector gets to the end sooner ("the reactor's lifetime is simply shortened") and the fuel ends up less poisoned than it would ideally have been.
With a gift of essentially free energy for a couple of decades, I'm sure some of 2+ million (700000 gallons at $3+ per gallon) they spend on gas (for generators) annually could be spend bringing in security personelle.
A million plus dollars buys a security force more than able to gaurd the perimeter around a complex not larger than a school building. Security is then essentially free for these people, and in fact they are still saving a lot of money per year in energy costs. Plus they are paying for a service in their community to people that will be living in their community. And those security people will spend money somewhere.
This solution may not be fesible when there are cheaper fuel alternatives, but out there it seems to make a lot of sense.
Why, o why must the sky fall when I've learned to fly?
Chernobyl was caused by _engineers_ testing removal of cores, they took all the cores out and couldn't get them back in.
What will cause more fear is idiots like you under selling the risks.
Pot. Kettle. Black.
First, by cores, you mean control rods. But you're still somewhat off track.
Second, Chernobyl was an unstable, bad design, without a containment building. It's design, RMBK 1000, was such that if things went bad, the nuclear reaction would continue, instead of shutting down.
In addition to the uranium, a nuclear reactor needs two things- a moderator (which actually promotes the fission chain reaction) and a thermal transfer mechanism, to take heat away and make electricity with it. This is beyond the control rods, which are used to shut down the plant.
In every plant in the US, water acts as both the moderator, and the heat transfer mechanism. Lose the water, and the chain reaction is unsustainable. You can't take away heat anymore, but the fission chain reaction slows down dramatically. This is what happened at Three Mile Island (TMI)- they lost the water. They melted parts of their core, but that was the extent of the meltdown. The reactor vessel did it's job and physically contained the uranium. The containment building did it's job, along with all the auxillary systems, and no appreciable radiation was released to the public. TMI proved that we can handle a disaster without endangering the public.
Back to chernobyl. The RMBK 1000 reactor used water as a heat transfer mechanism, and graphite as a moderator. So when they lost water cooling, the reaction actually increased in power, and this raised power output lead to a rapid spike in temperature and pressure, blowing the lid off the reactor core and destroying the building.
Moreover, if they attempt to sustain low power levels (20% of capacity), the system is unstable. Because the core was huge, it was possible to have pockets of reactivity that couldn't be well controlled. When the power level is low, the cooling water/heat transport flow is reduced, to keep proper operating temperatures. But because they had pockets of reactivity that could be greater than average, there could be local areas where the flow was inadequate, boiling off the water prematurely, and getting us back the increasing reactivity with water loss that I mentioned earlier. Hence, they where supposed to operate below 20% power.
As for the people, despite earlier problems at different plants, they were not aware of the aforementioned technical problems. The Soviet bueacracy prevented any useful exchanges on such subjects. This is not to excuse them from not knowing more about their plant, just to paint a picture.
The cause of this was ironically a safety experiment. When a nuke plant is shut down, it still produces a significant amount of heat that must be removed. Normally the power required to run the pumps to remove this heat comes off the grid from other power plants, but if the plant is disconnected from the grid, a diesel generator is used instead. It took them three minutes to start the diesels (as opposed to a ten second standard in the US), so the engineers thought that they could bridge this three minute gap by extracting power from the turbine while it was in the process of coasting to a stop.
In order to test this theory, they deactivated every single safety system the plant had, and brought the power levels down to 6%. I've already talked about why this was bad.
At the end of their 'safety test', they inserted the control rods successfully, and in a hurry, because they could tell they were losing control of the plant. Because of the horrible design, though, these control rods where insufficient to kill the chain reaction, and instead only displaced water, which brought the power levels up to 100 times normal. Kaboom. The 'successful' insertion of the control rods was the final event in an idiotic string of actions.
They had no understanding of the safety i
Alcohol, Tobacco and Firearms should be the name of a store, not a government agency.
Keep in mind that:
General thoughts, in no specific order...
/. would have to be implemented using little peices of paper, fine point pens, and hundreds of thousands of really, really tired carrier pigeons.
A) the "dirty bomb" (a current favorite among hte fear mongering media) made out of radioactive materials is generally NOTHING like the multiple-megaton weapons that make the big fancy mushroom clouda. These are bombs that expode conventionally, and through said explosion, scatter radioactive materials around an area, creating a hot zone that will possibly kill, probably sicken, some people right near the area, but mainly just go to scare the millions of people into knee-jerk reactions though non-understanding.
B) Making a cheap and nasty little dirty bomb can be easily done by stealing the Cesium 137 out of a few hospitals (canisters of it are used in x-ray machines - i think its an xray machine). The added benefit of this is that the material is a very fine powder that can get spread widely by the wind.
One of these canisters got loose in Brazil once. Resulted in killing four and made a few people sick. THe cleanup was a tad nasty. People heard about it, and thousands of them showed up at hospitals to get checked out for possible contamination. This was after local officials told them "Look, you were in the immediate area, youre going to be fine." People still stood on line at hospitals, choking hospital resources and generally fucking up their ability to take care of those that were really hurt.
[If you get a chance, find that Dirty Bomb special NOVA did a while back. This is the ref for that cesium info above]
Stealing a fat hunk of reactor core would involve about a million times work, and unless they wannt rub the thing against a cheese grater for a while, they're left with one solid hunk of radioactive material, which is fairly easy to handle, contain, and bury somewhere.
[again, go read that NOVA site.]
C) Your average goober (read: 98% of the population) is completely unaware of that fact that we're constantly being bombarded with "background radiation" every second of every day. They're also unaware that our skin does a pretty good job of fending that low-level shit off.
D) Imagine if mass media existed at today's level in Edison's time. Getting people to accept the fact that electricity was not going to jump out of an unused outlet (or a wire) and kill you [in everyday non-dubmass use] would be next to impossible, and
E) People Die. Its something we all do, and ya can't avoid it, so stop fucking scaring yourselves into non-action. You can only hope its not going to be horrible. Generally, not being a stupidass - and keeping yourself aware of (AWARE, not SCARED) the other stupidasses around you - will go a long way in accomplishing this.
s'wut i sed.
As far as the heavy metal runoff from uranium mining, it is no worse than that at any other heavy metal mine. Or a gold mine for that matter.
You can only drink 30 or 40 glasses of beer a day, no matter how rich you are.
-- Colonel Adolphus Busch
Do read about Hiroshima some time. Se how precisely the timing had to be constructed. Check the purity and mass and density specifications. Then try to construct a scenario in which a nuclear plant could even vaguly resemgle that.
Chernobyl is pretty much the worst that could happen, and there are plenty of safety precautions that could have prevented it.
Sig:Why copyright isn't a fundamental human right
Because of its design and small size, the Toshiba reactor can't overheat or melt down, he said, unlike what happened in the 1986 accident at Chernobyl that killed 30 people and spewed radiation across northern Europe.
While the new type of reactor might be perfectly safe, why do they spread "disinformation" then? Of course, the "blow up" of Chernobyl only costed about 30 lives. The cleaning up recruits of the USSR army had about 1000 falacities later. Seems they don't count.
Anyway, besides the credibility of the press release the question of how to take care about burned out units remains.
angel'o'sphere
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
One of the big concerns everyone seems to have with these things is "How are we going to guard them?"
This is so simple it hurts when it hits you in the fase.
Assuming these reactors really dont have a footprint much bigger than a warehouse, put them in places that are ALREADY heavily guarded.
Military bases, Prisons, and maybe some of the bigger Airports.
The actual core is buried in the ground (bury it DEEP, who fucking cares) and surrounded by dirt and concrete, so unless the Mole-Men get a bug up their ass, its doubtful an underground attack would go unnoticed. [all you'd need is a cheap seismograph and voila! You can pick up unusual digging.]
The surface building is in an area thats heavily guarded anyway, so all we really would need to do is make sure the current guards are doign their fucking job, which they're supposed to be doing in the first place.
Also, maybe the the death row inmates and the multiple-lifers can work on the crews in the buildings. Make that a trade off for big screen TVs or less shitty cells or something. These would be the same guys that got their shit together and now work the scared straight programs and do other truly useful functions in the prisons already.
As far as dealing with the waste products, I'd personally rather have to truck a treetrunk sized core to some bigass site in the middle of the desert every 20 years than belch a few more hundred thousand tons of shit into the air over that same time period. For fucks sake, we can protect 635 legislators and their staffs form terrorists, I'd think the logistics of a truck going one way slowly wouldn't be too hard.
This might be tough in Alaska, where folks are spread out all over the place, but should be fairly easy in the lower 48, and who says you cant put in a bank of four of these little cores in more densely populated areas? One AA battery is good, four is better, and only slightly harder to add in.
another thought: To make it even more idiot proof, take as many of the computers out amd make all the controlls big analog levers and handles, computers can do the monitoring. Remove the chance of the system itself being flummoxed by a busted motherboard, adn everyones happier (and busier!)
s'wut i sed.
This Toshiba design looks a bit like the South African pebble bed modular reactor and the General Atomics GT-MHR, so the idea is not really new.
Inuit officials have declared that another word for 'snow' will be introduced into their vocabulary, this time referring to 'irradiated, green, and glowing.'
UNIX: Find it, fsck it, forget it.
>>Go read about Hiroshima and Nagasaki. That's
>>what a bad nuclear accident will look like.
As others have pointed out, a nuclear power disaster would be *nothing* like Hiroshima. But even if it were... you know, i went to Hiroshima a couple of years ago. It's a thriving, growing metropolis. So is Nagasaki, for that matter.
Large scale reconstruction of Hiroshima had started by 1950. That's 5 years after the blast - which yeah, is bad, but it's certainly not 50,000 years. And, good grief, that's an actual nuclear bomb. Even the worst case nuclear accident is several *orders* of magnitude less severe. Yeah, radiation is dangerous, but the irrational fear far outstrips the reality.
I'll have to ask my uncle. He helped Bechtel build an oil refinery in northern Alberta...
This is not my sandwich.
In water the blue glow is caused by radioactive particles exceeding the speed of light. No, not the 3e8 m/ss speed of light in the universe. The slower speed of light in water.
The glow that one sometimes sees around radium or other elements is actually particles interacting with chemical impurities around it. You get much the same effect with a black light.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
The United States has not yet been able to find the permanent resting place for all of these spent nuclear materials. Currently all are on hold in temporary storage ponds etc at the various and sundry reactor sites around the world.
When someone solves the waste problem we'll be on to something. Until then I think we should wait.
-Scott scott@surrealistic.org
I'm a chemical engineering senior at the UofWisconsin Madison. Two years ago I took a nuclear reactor lab class here at the UW where we learned about and operated the college's reactor (1 megawatt thermal -- lots of good info at this site). It was one of our lab exercises to rapidly remove the control blades (flat plates in this reactor -- not rods) all the way to create a pulse. A *pulse*. That is, even with the blades removed, the reactor would not melt down. (can see it at this site) Since the rxr was water-moderated, there is no conceivable mode of operation which would allow the core to melt. In fact, it's so safe that it was built right in the middle of campus. And this was designed back in the day...
The town is only about 700 odd people. One possibility is that if this gets near fielding, there will be a call by the anti-nuke groups for people to move there and basicly take over the town in order to stop it. There will also, of course, be lawsuit after lawsuit to delay it.
It's a must win for the antinuclear movement.
They'll view with alarm the small size, and especially the very low installation cost which makes it hard for long delays to bankrupt by increasing the cost of working capital.
That no plant has been ordered in the US for decades is a huge political point for them, and they'd see this as the camel getting a nose into the tent. I expect a bitter fight by them.
Hava a look here.
Not to flame the prior poster, I just can't resist the chance to clarify some common misconceptions about nuclear reactors. # 1 - A critical reactor is bad; A critical reactor is a stable reactor. K effective is the ratio of neutrons in the current generation vs neutrons in the last generation. A critical reactor is when K effective is equal to one. That is the number of neutrons is not changing. ( that is the reactor power is stable) A sub critical reactor is when K effective is less than one ( The reactor power is going down.) A supercritical reactor is when K effective is greater than one( the reactor power is going up) A nuclear reactor goes through all three of the above states during normal operation. I've taken a reactor critical hundreds of times and most of my time spent operating a nuclear reactor is to maintain criticallity at a stable power. Obviously going up in power too fast is a bad thing thing. Fallacy 2 - A nuclear reactor blow up like a nuclear weapon. Nuclear reactors don't work in such a way as to support a nuclear explosion. There are several good posts about Chernobyl. This was just about a worst case accident, but is was a steam explosion.
"Sure they say it's impossible to spill (radioactive material) for it to get out. But nothing in this world is impossible," he said.
Except, of course, for the public to rationally consider anything at all with "nuclear" in its name. That is really impossible.
What is it with people and "nuclear"? This reactor is suggested by the Japanese of all people. They were nuked. Twice. If anyone should automatically shut down his brain and cringe at the sound "nuclear", it should be them. Yet they seem to be thinking rationally about it. In the meanwhile, it is the Americans who nuked them who black out when hearing the word. What is this, some sort of guilt trip?
Wait, I got it. These Japanese are also scared of nuclear power. But they hell-bent on revenge! They'll install these miniature nuclear plants all over the USA, and at a predetermined time will cause them all to explode, killing everyone in the continent! Notice they don't suggest it be used in Japan? Launch a pre-emptive strike now!
Okay, help me out here. The article says that cooling with water leads to corrosion, so they're using liquid sodium instead. Then they use the sodium to boil water.
I can understand why they don't want water corroding away at the area around the uranium, thereby releasing U into the surroundings. What I don't understand is why they're not worried about the water corroding a hole in the heat exchanger and coming into contact with the sodium, causing an explosion.
You'd think they'd rather have uranium-contaminated water slowly leaking out of the reactor, rather than a large explosion scattering uranium dust all over the surrounding countryside. Can somebody clarify why the latter isn't a problem?
"It sure was strange to see something on Usenet about me that didn't involve Klingon gang rape." -- Wil Wheaton
The French DO reprocess Nuclear Wastes at the COGEMA facility at La Hague, near Cherbourg. The facility reprocesses French, Japanese, German, Belgian, Swiss and Dutch Nuclear waste. Much of the reprocessed fuel is put back into reactors as MOX fuel. You can lear more at:
http://www.cogemalahague.com