Fukushima Meltdown Might Have Come With Earthquake, Not Tsunami 172
formfeed writes "As the data from the Fukushima reactor is being reviewed it looks like the meltdown happened much earlier: '[T]he fuel rods in the No. 1 reactor were completely exposed to the air and rapidly heating five hours after the quake.' Apparently, the earthquake had caused a crack in the containment vessel. Which means, that even without the generators failing, the meltdown might still have happened. With this new data, it seems a similar incident could happen in an earthquake zone even without a tsunami."
Uh... summary? (Score:5, Insightful)
Article:
The operator of the crippled Fukushima Daiichi nuclear plant said it is studying whether the facility's reactors were damaged in the March 11 earthquake even before the massive tsunami that followed cut off power and sent the reactors into crisis.
Kyodo news agency quoted an unnamed source at the utility on Sunday as saying that the No. 1 reactor might have suffered structural damage in the earthquake that caused a release of radiation separate from the tsunami.
Summary:
Apparently, the earthquake had caused a crack in the containment vessel.
I'm not sure how the summary writer came to that conclusion... Shouldn't we wait for an actual report/finding before stating that?
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Welcome to /. leave facts at the door along with all thoughts of compromise as your solutions and knowledge are always right on all topics
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Shouldn't we wait for an actual report/finding before stating that?
This slow release of news is just salamitaktik to reduce public outcry. Tepco have known from the start that the reactors melted down and breached containment.
Of course, as usual with reputation engineering, it's only made things much worse. This was an international incident from the beginning, and resources from around the world should have been used to mitigate the damage.
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Your evidence for this, in particular focussing on your technical term "known"? What sensor readings would they have had that would tell them containment has been breached, considering that simultaneously they also had shutdown operations happening, switchover of circulating systems, ground accelerations from the quake itself and aftershocks ...
But hey, I just have to work with much simpler sensor systems in a not-much
Re:Uh... summary? (Score:4, Informative)
[reactors...] breached containment. [citation needed]
'Engineers from the Tokyo Electric Power company (Tepco) entered the No.1 reactor at the end of last week for the first time and saw the top five feet or so of the core’s 13ft-long fuel rods had been exposed to the air and melted down.
Previously, Tepco believed that the core of the reactor was submerged in enough water to keep it stable and that only 55 per cent of the core had been damaged.
Now the company is worried that the molten pool of radioactive fuel may have burned a hole through the bottom of the containment vessel, causing water to leak.
“We will have to revise our plans,” said Junichi Matsumoto, a spokesman for Tepco. “We cannot deny the possibility that a hole in the pressure vessel caused water to leak”.'
AFAIK, all the "leaking radioactive material" stories are about the spent fuel pond(s) not the reactor cores.
Leaking?
"United States government engineers sent to help with the crisis in Japan are warning that the troubled nuclear plant there is facing a wide array of fresh threats that could persist indefinitely, and that in some cases are expected to increase as a result of the very measures being taken to keep the plant stable, according to a confidential assessment prepared by the Nuclear Regulatory Commission."
"The document also suggests that fragments or particles of nuclear fuel from spent fuel pools above the reactors were blown “up to one mile from the units,” and that pieces of highly radioactive material fell between two units and had to be “bulldozed over,” presumably to protect workers at the site. The ejection of nuclear material, which may have occurred during one of the earlier hydrogen explosions, may indicate more extensive damage to the extremely radioactive pools than previously disclosed."
http://www.nytimes.com/2011/04/06/world/asia/06nuclear.html?_r=2&hp [nytimes.com]
Re:Uh... summary? (Score:4, Insightful)
If the containment vessel isn't leaking, how is all of the highly-radioactive, plutonium-bearing water accumulating outside of the containment vessel?
Lots of very respected sources are reporting that there was damage to the containment vessel in reactors 1 through 3, quoting multiple figures in the government and TEPCO. I'm going to trust their ability to cross-check their reporting more than your "linked report" which is just a second-hand summary of news reported by one source, not some official document.
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If you have *airborne* plutonium, you have *huge* problems. The boiling point of plutonium is nearly 6000 degrees Fahrenheit. And even if you're getting plutonium from water, it inherently means that the zirconium cladding has melted off the rods. Arguing that that this happened in the cooling ponds isn't exactly going to win you any brownie points in the "Nucle
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Zirconium cladding in the spent fuel ponds does not occur as part of a core meltdown. This would mean a spent fuel pond meltdown, which would be a huge disaster in its own right (no containment at all)
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This was a big deal - level 7 nuclear disaster.
That's a fairly useless scale ( read up [wikipedia.org] on the "criteria").
This is worse than TMI (which had barely measurable radioactive release), but nowhere near as bad as Chernobyl (AFAIK, so far).
Chernobyl had no sealed containment vessel, and the fuel was allowed to reach super-high temperatures which burned the graphite moderator directly into the atmosphere, where wind carried it for miles - which is REALLY REALLY BAD.
The containment vessel was breached.
Again, [citation needed].
See my links and quotes in this post. [slashdot.org]
The spent fuel rods became radioactive because their pools became depleted.
The spent fuel rods are always rad
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Chernobyl also had a fraction as much nuclear material on-hand, and had no plutonium-burning reactors. Also, the spent fuel ponds had no containment structure around them at Fukushima, only the core.
Anyway, I think it's way too soon to make any calls as to how bad this is going to be in the long run. The real question is how much cesium is working its way into the soil, houses, water, etc around the plant. All that can be done for now is to try to minimize it.
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All uranium reactors produce, and burn, plutonium. Chernobyl released plutonium. The MOX fuel at one of the Fukushima reactors might have had more plutonium, but so far as I know the amount released has so far been small.
Re:Uh... summary? (Score:5, Funny)
You should be modded -1 Factual or -1 On-topic :)
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Karma is totally overrated... I've got my +1, and I haven't written anything useful in YEARS... :-)
Re:Uh... summary? (Score:5, Insightful)
Here's a better writeup:
Mainichi Daily News: http://mdn.mainichi.jp/mdnnews/news/20110517p2a00m0na008000c.html [mainichi.jp]
taz (German): http://taz.de/1/zukunft/umwelt/artikel/1/tepcos-verteidigung-broeckelt/ [taz.de]
According to these articles, reactor no. 1 experienced some kind of problem (sudden drop of pressure) 10 minutes after the earthquake and well before the tsunami struck. The crew then had some troubles with the cooling system of said reactor but the articles are pretty vague in that regard. This is according to TEPCO's own reports.
Anyway, I've always maintained that the assertion that the earthquake did no damage in Fukushima (and therefore other nuclear plants are "safe") was nothing but a myth pushed by nuclear apologists in their own self-interest. It's nice to see some factual reporting backing up my thesis, by the nuke operator no less.
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To me this does seem like a major design defect. The reactors were designed to withstand large amounts of lateral acceleration, but not as much as the earthquake cause. It is somewhat understandable that such a large tsunami was not anticipated but this is not the first magnitude 9 earthquake since accurate record keeping began.
Other plants have been inspected and 99% of them are fine, although that was expected since they were further from the epicentre and thus were exposed to less lateral movement. If th
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Speaking of war, in all the press coverage of earthquake-proofing the react
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Probably because, in war, no sane military is going to be shooting at the nuclear plants; it would be as bad, if not worse, as setting off an actual nuke.
Worst case, they'd be looking to take out the power switch yard, a much softer target, which would prevent the distribution of the power and therefore force the plant to shut down.
no sane military ... (Score:3)
As we have seen lately, the keyword there is 'sane'. Unfortunately, sanity is not a prerequisite for having an army, running a country, or starting a war. (Sanity may not even be particularly useful in those scenarios.) Some parts of the world seem to my untrained eye as a basically a contest to see who's the craziest b.....d in the neighborhood. Whoever wins becomes boss - for a while.
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Look at nuclear weapons - despite quite a few countries having them at this point, none have been used. Countries with working nuclear reactors also tend to have functioning militaries, to the point that competency would be required in a military attack against them.
Competency and sanity do tend to go together, at least when it comes to the low level of sanity it takes to know [i]not to bomb or shell a nuclear plant[/i].
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Look at nuclear weapons - despite quite a few countries having them at this point, only a few have been used.
FTFY.
The world is afraid some rogue state like North Korea might launch a nuclear attack, but so far only one state has shown it is willing to go the whole way and actually do it. It's not North Korea, China, Iran, Pakistan, ..., but much closer to home (for most Slashdot readers). I'll leave it to others to comment on what that might or might not tell you about the sanity of that state.
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Doh!
Yeah, I should have more said 'none have been used since the effects of radiation became more well known'. Like I said though - you don't actually have to bomb the nuclear plant; just the switching yard for the power. Losing the grid connection will cause it to SCRAM automatically; they aren't designed to dump the power locally.
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Well I don't think there are any nuclear facilities that would survive having an airliner flown into them either so... Yeah, basically if there was a real war we would be screwed, but realistically I don't think it is likely. Countries with a modern high-tech military are basically at a standoff with each other because the consequences of even a conventional war would be utter devastating for both sides. That leaves countries like North Korea, but I don't think even they are mad enough to start a real war w
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In the US in the 1960's nuclear power plant containment domes were designed to survive a Boeing 707 being flown into them. Of course there are other parts of the plant outside of the containment dome that could be affected.
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Considering that the example of utter devastation in WWI didn't prevent WWII, and considering that the global political landscape can shift within the 50-ish year lifespan of any reactor (rise of China, re-alignment of the Middle East, etc.), and considering the proliferation of nuclear reactors into possibly unstable countries (India, Iran, China, etc.) it's hard to claim that war is an unlikely threat to nuclear reactors. IMHO. History is long and unforgiving.
Consider also the revealed history of possi
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In WWI a lot of soldiers were killed but most of each countries civilian populations were untouched. There were a few attempts like the bombing of London by airships and very long range artillery but nothing on the scale of the mass bombings of WWII.
That is the key difference. When WWII came around it was possible to target factories and other infrastructure that were previously impossible to get at.
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But you see, that's not acceptable. You can't just account for known unknowns. You also have to factor in the risk of unknown unknowns. It's simply not good enough to say, "We've
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You have to pick some cut-off point, otherwise there is no limit to the safety features required.
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But that limit should not be "What we've already seen happen, plus a couple feet". When the disaster potential is on such a great scale, you need to assume "we ain't seen nothing yet." And if that assumption is too expensive? Then you don't do it.
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My great-grandaddy was an engineer/doctor/botanist in India in the mid-1800s. One of his claims to fame was a bridge over a river canyon, which had been washed out repeatedly. So he walked 100 miles upstream and 100 miles downstream, and interviewed the chiefs and the elders of each village and tribe along the river, asking how high the water went in their lifetimes, in their ancestors lifetimes, and in their legends. He assembled a 500 year history of the river's floods. Then he had the new bridge buil
Re:Uh... summary? (Score:4, Interesting)
Well, it was also fairly obvious given the following:
- Among the long history of safety procedure fraud at Fukushima, by TEPCO, were instances where repairs were performed using procedures that were not approved by standards, but signed off as otherwise. (therefore - plant infrastructure which may have been *designed* to withstand certain g acceleration forces of an earthquake in 1971, may not be able to withstand those forces 40 years later, after these un-approved, but fraudulently certified repairs.) - The article which mentions these variances does not provide specifics.
- When Unit 1, and 3 exploded, the roofs of the building blew off. This indicates that the hydrogen had been generated in a reactor core at over 2200 degrees C, in the presence of water, and escaped the primary cooling system, venting into the reactor building's structure through the particle scrubbers, and exploded. A hydrogen explosion is not good, of course, but only indicative of a loss-of-cooling, at a minimum. Many experts will say that hydrogen generation is pretty much a sure sign of melting; it's not precise, but when you're in the ballpark, in a nuclear reactor, things can get very unstable very quickly, (like, milliseconds-quickly). None of these units had instrumentation, or controls, or active cooling going on. As hot byproducts are released - they have much lower melting points than the Uranium fuel, and they can migrate around, and collect in different states (or chemically react with eachother, and have a completely different set of properties - and these properties could be caustic, or explosive) . . . and cause hotspots, regions of high flux. (while some byproducts absorb neutrons and slow the reaction down). Pretty much all bets are off, as far as predicting what's going to happen.
Strictly speaking, hydrogen generation does not mean melting HAD to happen. But in this situation, it was highly improbable that melting wasn't happening in conjunction with that.
(and the hydrogen generation did not necessarily happen at the time of the explosions - the explosions happened later).
- When Unit 2 exploded, the explosion blew out the side of the base of the building, through the condenser, in the primary cooling. This means that the hydrogen collected and ignited in the primary cooling system. This also means that there was enough heat in the condenser to provide ignition. This could have been due to excessive steam pressure, (compression-ignition) - with oxygen leaking IN through structural cracks. It strongly suggests that Unit 2 was damaged structurally, (the concrete torus), in the quake. It could be that thermally hot byproducts or corium caused the ignition in the RPV, maybe with an oxygen isotope (I don't know if this is possible or not, probably not), or dissasociated water,(weird isotope chemistry?) or the ignition source made it's way into the torus (which would mean, holey RPV+holey primary cooling = open core). I can't really say what the ignition source could have been, but the presence of oxygen is the crazy bit, and the simplest explanation is structural issues in the concrete (or connecting cooling pipes/valves).
I think it was pretty idiotic and foolish (okay. . . unprofessional?) for TEPCO to state, in the immediate aftermath of the first hydrogen explosion, that they knew that the RPV was intact. They couldn't get instrument readings, or even a visual inspection for many days after that explosion to even get a half-assed confirmation of that statement. It was this kind of fumbling around and PR mismanagement that does the most damage to the industry's credibility. It would have been better for them to state what they definitely knew - what data they had, and the range of possibilities that it could have meant. That first hydrogen explosion was absolutely the time to press the panic button and evacuate residents.
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Remember the first rule of yellow journalism.
If there's no news to be had, generate an eye-catching, inaccurate headline.
Then make shit up.
"Kyodo news agency quoted an unnamed source"
This is essentially a license to freely spew anything. Regardless of the facts.
Now comes the time when they attempt to rewrite what actually happened, and replace it with a "nuclear horror" scenario.
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Apparently you missed "quoted an unnamed source".
I can "quote an unnamed source" who says that the moon landings were faked on a soundstage.
Thanks for playing!
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From TFA:
The utility said on Sunday that a review of data from March 11 suggested that the fuel rods in the No. 1 reactor were completely exposed to the air and rapidly heating five hours after the quake.
and
Kyodo news agency quoted an unnamed source at the utility on Sunday as saying that the No. 1 reactor might have suffered structural damage in the earthquake that caused a release of radiation separate from the tsunami.
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This utility has, so far, always said "might have" when they meant "have". They knew right away that there had been a meltdown, but instead of admitting it, they waited until it had been proven by a visual inspection. And for future reference "structural damage" is jargon for crack when you are referring to a containment vessel.
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nuclear experts
Not that I disagree with Gundersen, but one person does not a group make.
Misleading Title As Usual (Score:3, Informative)
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It need not melt in the 40-50 minutes as you suggest. When the tsunami came only the diesel generators failed. The battery backup was still working. Only when the batteries wound down was the effect of the tsunami felt - i.e. generators were offline. So, there was ample time for the meltdown due to structural damage to occur.
I am not sure about your other points - only pointing out that the timeline need not be as stringent as you were mentioning.
Battery Power (Score:5, Informative)
"Documents released by Tepco Monday showed the isolation condenser— an emergency cooling system installed on Reactor No. 1 before the quake as a final resort in case of a total loss of power—worked only sporadically, if at all. Tepco officials explained that somebody appears to have manually closed the valves on the condenser soon after the March 11 quake—but before the tsunami hit about an hour later—to control the fluctuating pressure inside the reactor. Reopening the valves required battery power, so those valves likely couldn't be opened because the tsunami damaged the backup batteries.
If the valves hadn't been shut, things might have turned out differently. Temperatures in the reactor climbed faster than initially expected, causing more and faster damage. Tepco admitted this week the problems at Reactor 1 were far worse than originally thought. Its new projection shows fuel may have started melting rapidly only five hours after the March 11 quake. By 6:50 a.m. March 12, the fuel was likely in a heap at the bottom of the vessel. "
Battery power was lost apparently.
Unit 4 explosion from Unit 3 hydrogen (Score:3)
"According to Tepco, hyrogen produced in the overheating of the reactor core at unit 3 flowed through a gas-treatment line and entered unit No. 4 because of a breakdown of valves. Hydrogen leaked from ducts in the second, third and fourth floors of the reactor building at unit No. 4 and ignited a massive explosion."
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Depends on what part of the cooling system. The main cooling pumps indeed do take a lot of electric power.
One of the backup systems, the RCIC, uses residual steam pressure to inject cooling water into the reactor. The valves and controls for that system require electric power, but batteries can supply that.
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8 hours on units 2 and 3; which have a different cooling makeup.
1 may have only had 6 hours.
Also, it may have been a sensor issue.
http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110515e10.pdf [tepco.co.jp]
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Re:Misleading Title As Usual (Score:5, Interesting)
If there was a crack at the bottom of the RPV, the pressure would have pushed water out rather quickly.
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480/0.5*0.07 = 67.2 MW thermal
More likely it's in the mid 30s (or even low 30s) for efficiency, so you end up around 96 MW thermal immediately after shutdown.
Re:Misleading Title As Usual (Score:5, Interesting)
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By way, as a noob and an AC, the link isn't in html - maybe some moderator will fix it.
You REALLY must be new here... /. mods have one job: to create misleading and false headlines and ensure that summaries are less accurate when they are posted than when they are submitted. In this case, they have for some reason replaced "pressure vessel" with "containment vessel", presumably to make it clear to absolutely everyone that they know nothing about the technology of nuclear power.
That's an excellent link, though, and the data indicate that the scenario described in the article is pretty unlike
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Reactor 1 is 1360MWt. Approximate decay heat at shutdown is ~6.6% ~ 90MW. After 10 mins, it's ~2.2% = ~ 30MW, after 1hr, it's ~1.5% = ~ 20MW.
The original poster failed to convert MW to kJ. 1MW/s = 2000 kJ/s, failed to adjust for the water temperature/pressure (heat of vaporization is lower at high temp&pressure), and failed to adjust for the rapid decrease in decay heat during the first hour.
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Thanks for the correction on the conversion factor, don't know where I got my conversion factor (I can't find it now).
MW/s is an unusual unit, but given the rapid and approximately logarithmic decrease in decay heat [wikipedia.org] production in the first hour, using a larger time window would be bizarre and produce questionable results. It's also what the original poster used, so for consistency and clarity, I used it too (just with an incorrect conversion factor).
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It first has to evaporate or otherwise evacuate the water inside the reactor...
I'm thinking possible crack in the reactor vessel, and that the fucktard OP doesn't know the difference between reactor and containment vessels.
Quality of sources (Score:3)
While I am not sure about the quality of this article and its unclear how some of these conclusions are reached should this events be corroborated later this is a big deal. If true it kinda throws out some of the hey it stood up to way more than was ever expected, these things really are safe narrative.
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It's funny because what is happening in Japan is exactly why Nuclear Power is SAFE!
An earthquake 7 times more powerful than the biggest it was built for hit, and all that happened to the reactors that didn't shut down cleanly was a small amount of radioactive noble gases, which decay within minutes. Even if the cores DO melt, they're safely contained in ... wait for it... containment chambers!
People don't realize the amount of engineering that goes into nuclear to make it safe.
As I always say: containment chambers indeed!
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Indeed. Radiation levels around the plant prove beyond any doubt that the amount of radiation release was neither small, nor did it decay within minutes, nor was it contained in any containment chambers. It's amazing how very confidently people can be so extremely wrong.
We're still right about the radiation killing approximately nobody*.
The radiation release is still small in scope compared to Chernobyl, for a plant commissioned in 1971, which actually makes it OLDER than chernobyl by 6 years(commissioned in 1977). Reactor #4 wasn't completed until 1983.
Personally, I'd like to see us decommissioning these old reactors in faver of newer, safer reactors.
*It's possible that it might, sometime in the future, trigger a cancer for one of the workers.
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... yet. What you conveniently fail to consider is that nobody's concerned about the acute effects of radation, except possibly for the plant workers on site; people are wary of the long-term consequences, and rightly so. Also cancers are just part of the story, there are also the teratogenic effects to consider, which open a whole new chapter of this grim tale.
If you want to start playing that game, I can always start pulling out the statistics for coal when it's operating 'as normal' as opposed to an emergency.
As I said in an earlier post, the nuclear apologists have adopted lately a new and very convenient frame of reference for nuclear disasters, i.e., Chernobyl = very serious (obviously, it was the stinking commies), and even that part is not clear, anything less = a walk in the park, obviously because you see, it's "not as bad as Chernobyl". Well a third grader knows that "smaller than huge" doesn't equal small, in fact it can perfectly be huge too.
I've had risk management and safety analysis training(though I'm not an expert). We now know that a major accident involving a significant uncontrolled containment leak is, roughly, a 1 every 25 years event. We also can start figuring out the cost of it.
Even figuring on a Chernobyl level event every 25 years, it's still better than coal. Affordable ele
Cheap, Defective Containment Vessel (Score:5, Insightful)
Mitsuhiko+Tanaka [google.com] was an engineer who led Fukushima's building of the reactor vessel. He told Japan's government following Chernobyl's explosion that he had helped TEPCO cover up the fact that the reactor vessel was damaged during its manufacture. Japan's government ignored him and continued to relicense Fukushima for many years past either his warning or Fukushima's designed lifecycle.
This is the problem with nukes: the people in its industry and government cooperate to protect the corporate profits rather than the public even when those two interests are in conflict. Regardless of technical solutions to technical problems (which cost money and are ignored when the corporation can get away with it), the problem that's proven impossible to solve is the failure to properly regulate the rich essential monopolies owning or running the nuke plants.
Which is a problem not just where earthquakes and tsunamis are the particular risk. It's a problem in countries like Russia, Japan and the US.
That is the risk that nuke boosters never admit: the risk of human error in the regulation and oversight, not just the engineers. These nukes are too risky for our corruptible industrialists and government people to be trusted with.
"There's no difference between theory and practice - in theory. In practice, there is a difference." - Yogi Berra (paraphrase)
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You realize that is a problem with any industry when government is close to the people that run anything, right? Nukes, oil, coal, "green" energy. You name it. When government gets in bed with companies, they end up looking the other way every time.
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You realize that is a problem with any industry when government is close to the people that run anything, right? Nukes, oil, coal, "green" energy. You name it. When government gets in bed with companies, they end up looking the other way every time.
What you say is true. The key distinction is that when something goes wrong with those other industries, you don't ruin all the real estate value in an area the size of a small state.
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Not really. Things are already more-or-less back to normal in the gulf. A nuclear exclusion zone would have a much bigger long term effect on property values.
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Yep, we can't trust our government or companies to do anything competently. For our own safety, we should clearly ban:
- Nuclear plants
- Coal plants
- Oil plants
- Cars
- Supermarkets
- Highways
- Bombs
- Guns
- Tanks
- The police
- The fire service
- The public health service (outside the US)
- Banks
- Trains
- Computer components
- Boats
- Aeroplanes
- Busses
I mean it's either that, or come up with some kind of system for keeping these entities accountable, so that we would be able to benefit from these things. But sinc
Re:Cheap, Defective Containment Vessel (Score:5, Insightful)
Yep, we can't trust our government or companies to do anything competently. For our own safety, we should clearly ban:
Nuclear plants are unique amongst these things in that their failure modes are:
1) rapid
2) complex
3) expensive
The speed comes from the energy density of the core, which is many orders of magnitude higher than for any other power source. A typical nuclear plant contains something like the equivalent of 100,000 boxcars of coal in its fuel rods, and while only a tiny fraction of that can be released over a reasonably short interval, only a tiny fraction has to be released over a relatively short interval to ruin the core.
Reactor kinetics are complicated and the cooling and control systems more-so. Complexity is a bigger issue in second and third generation designs--one could even say that the whole point of fourth generation designs is to engineer out as much complexity as possible. However, there is always going to be a fairly high level of complexity for anything beyond the "nuclear battery" type reactors (which to my mind are probably viable sources of energy in the long term.) The high energy density and consequent rapid pace of events during failure mean that the humans involved in the process are going to frequently make bad choices.
The cost is the big problem: a failure in a coal plant results in some nasty chemicals released into the environment, maybe some people burned in a steam explosion or the like. But it is very hard to create a coal plant disaster that writes off the capital investment or exposes the operator to the kind of widespread liability that nuclear disasters do.
So anyone who is not innumerate realizes that the risk-cost/benefit trade-off for nuclear power is very different from most other technologies. The benefits are significant, but a long, long way from "power too cheap to meter", which was the original promise of nuclear power. The costs are having an event like Windscale or Chernobyl or Fukushima every decade or two. For numerate people, the trade-offs involved are not a slam-dunk on either side.
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Ironically, with new plant technologies, none of the events are even possible.
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Any nuke plant can suffer a breach of containment.
Physical impossibilities: (Score:2)
"Bullshit !
There is no safe nuclear power. There will never be.
It's just physically impossible"
Indeed. The Carrington Event [wikipedia.org] back in the 1859 shows that the biggest nuclear power source in the solar system is fraught with danger for our modern world.
In fact it almost certainly will one day destroy the earth.
We should all lobby the government to immediately start research to extinguish the sun.
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an event like Windscale or Chernobyl or Fukushima every decade or two
Ludicrous to compare these with modern plants. These were all extremely old, and very badly run.
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It's ludicrous to expect that any plant won't be badly run.
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What you're not getting is that most plants are not "modern" at all. In fact, depending on what you mean, none of them are are since they haven't build any Generation IV nukes yet.
Also, Chernobyl Reactor 4 had only been operating 3 years before it exploded, so it's not like it was extremely old when it went up. It was state of the art, and brand new. Obviously it was poorly run though.
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Granted there were safety concerns, but the design has benefits too. The type of reactor is capable of using un-enriched uranium, though the commercial designs could not, and fuel is removed and replaced while the reactor is in operation. Yeah, the thermal feedback and the lack of containment (necessary to allow the fuel to be replaced while operating) is a huge draw-back. I guess they felt it was worthwhile at the time. It was designed before the three mile island accident, so they thought adequate safe
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Yeah, the thermal feedback and the lack of containment (necessary to allow the fuel to be replaced while operating) is a huge draw-back.
The confusion between "pressure vessel" and "containment" is one of the most frustrating thing about this whole discussion, although it does have the useful side-effect of marking the ignorant.
Reactors like the CANDU, which run on natural uranium and can be refueled while running don't have a pressure vessel of the kind a conventional PWR or BWR does. Dunno what the RMBK (Chernobyl) design has but the CANDU uses "calandria" tubes that contain the fuel rods. The refueling machine works on one tube at a tim
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The problem
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All you're doing is saying that concentrated dangers are more worthy of avoidance than distributed dangers simply because they're concentrated.
Not at all. I'm saying that coal plants fail in ways that are cheaper than nuclear plant failures. This is trivially true. I don't know of any case in the past fifty years where a coal plant failure has led to a complete loss of capital investment of the kind that routinely happens in relatively trivial nuclear plant disasters. If Fukushima were a coal plant it would be back in operation today, not written-off.
This has nothing to do with danger, which is fairly trivial in both cases, albeit greater for
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they are dangerous and they need to be built properly, I.E. NOT WITH A PROFIT MOTIVE
What a strange thing to say. I fly in aircraft built with a profit motive now and then, and haven't noticed that the motive of the builders particularly affects the dangers involved. Subsidized, state-run airlines like Aeroflot have no particular advantage over commercial airlines.
Why do you think the motive of the builders matters? The people who built Chernobyl were not motivated by profit. Nor were the people who built Windscale.
Bad engineering is a product of human beings, and it isn't like we live
Fault Tolerances . . . (Score:2)
I honestly think some people have a mental disability which prevents them from assessing risk rationally. They will be the end of us all.
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After they fail spectacularly, how many of the above continue to be deadly for longer than mammals have existed?
I hope you don't really think nuclear accidents can do anything like that, since that would mean you're actually talking about something you don't understand. I'm actually hoping you're trolling.
Isotopes with long half-lives aren't very radioactive. Isotopes with short half-lives are very radioactive. Isotopes with long-half-lives are around a long time. Isotopes with short half-lives disappear quickly.
This means that anything left after 220 million years (the time span you mentioned) will be extremely weak
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External radiation isn't nearly as big of deal as internal radiation and heavy metal toxicity.
Plutonium and uranium don't go away very quickly, even on geologic timescales. Once in the biosphere, they keep getting recycled (even with phytoremediation, you still gotta do something with the plant bound heavy metals).
From what I hear doubt has been cast on the "lung hotspot" theory of radiation-induced cancer, which should make lingering radioactives much less dangerous.
As for heavy metal toxicity, then we get to the advantages of nuclear: a reactor is a relatively small thing. Most of it is supporting equipment. Put differently, there isn't enough of the stuff to make an area uninhabitable for a long time.
Why should we as a species accept that kind of downside just to boil water? Oh, and before the slashdot-nuke-lovers start their "coal,coal,coal" chant, fuck coal too. Another shitty way to boil water.
For a million reasons. You have to provide answers to a million questions to get away from coal and nuclear. No one
Re:Cheap, Defective Containment Vessel (Score:5, Interesting)
You also have cultural issues at play. People like to point out how there was virtually no looting after the tsunami, and rightly so, but the downside of that same culture is a lack of whistle-blowing. Japan is still in many ways a Confucian society, and as such there is very little in the way of whistle blowing. And even when there is, people tend not to believe the whistle blower over his "superiors" at work because well, they are his superiors......
That being said, I would be willing to bet Japan goes from the rich country with the worst nuclear safety record to having one of the best. The Japanese throughout history have been a society that is very poor at initiating change, but the best at adapting to it, unfortunately it takes a huge shock for them to really change anything. Case in point, their air safety record. Japan used to have one of the worst air safety records around, but thanks to a string of major accidents in the 60s, and one huge accident(deadliest single airline crash in history) in the 80s, they now have probably the best air traffic safety records on the planet. There have been no passenger deaths in Japan since 1994, and there has only been one fatal incident involving a cargo jet. Considering the amount of air traffic both in Japan and from abroad, that is pretty damn impressive. Doubly so when you consider how small the airports are and how many flights they have to get in and out. The airline industry suffered from a lot of the same problems the nuclear industry does, rubber stamping, no whistle blowing etc. Hopefully this will serve as a wakeup call to the Japanese much in the way the major air accidents did.
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Actually they are not really a Confucian society. That never picked up here.
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Actually it's more likely you just couldn't find a CEO anymore. Shareholders want profits, a CEO won't keep his position for long if always spending them on "safety".
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Even faster CEOs won't take on such personal liability, at least not without compensation levels that make the current ludicrous levels look cheap.
They'll take a job at the local investment bank instead, where the only safety issues are paper cuts and RSI from counting the bags of money.
The good news... (Score:2)
Let's hope that they can help save the planet and themselves with their ingenuity, precision and technological advances.
LNG (Score:2)
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No they aren't. There are people talking about it, but even the most basic look at the logistics make it impossible to do. Japan is already pretty efficient.
Time for some slashdotters to eat crow (Score:5, Insightful)
I wouldn't say that I am anti-nuclear, but I do think it can be dangerous. Especially with the corner cutting that a lot of corporations try to use to save money. I was struck by this news on how many times I saw a pro-nuclear slashdotter post how the power plant had survived the earthquake just fine. Many people were saying how it was an amazing triumph of engineering that it could withstand the quake that was ten times what it was designed for. If only they had put the pumps up on stilts or someplace where the tsunami would not have caused the damage, everything would have been just fine. I guess that was just a bunch of wishfull thinking now huh? Sure, I understand that at the time it had looked like it survived the earthquake without damage. But you end up losing some credibility and start to look like a fool when it turns out you were completely wrong because you didn't yet have all the facts.
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I wouldn't say that I am anti-nuclear, but I do think it can be dangerous. Especially with the corner cutting that a lot of corporations try to use to save money.
Well, when there are coal mining accidents at least it does not affect the public at large, otherwise it's the same corporate behavior whatever the energy source.
Many people were saying how it was an amazing triumph of engineering that it could withstand the quake that was ten times what it was designed for.
That still leaves 3 more reactors on the "triumph" side. And I wonder how no.1 would have fared if the valve hadn't been close, if it was human error. There's not enough information to form an educated opinion yet.
But you end up losing some credibility and start to look like a fool when it turns out you were completely wrong because you didn't yet have all the facts.
Then again, the previous stories were filled with rabid anti-nuke (or trolls, same thing) who said things semantically equivalent to "OM
Um so what? (Score:2)
So what you are saying that *maybe* the plant failed during the largest earthquake in recorded history, that was far beyond the building specifications that the plant was built to resist, rather than after when it got hit by the largest tidal wave in history? This is also the first time in history that this has happened.
I bet the plant wasn't built to resist a direct comet strike either.
That all said, you can bet any new plants will have much more rigorous earthquake building specifications which is a good
What bothers me (the zycronium fuel rod claddings) (Score:2, Interesting)
I've always been a big nuclear supporter of safe nuclear power, and, by safe, I mean ones where the core can reliably melt down to puddle with very minimal impact on the environment around. The thing that bothers me is that I used to believe our current nuclear plants could do this. I am no longer convinced. Indeed, I am openly concerned this is not the case.
In the four cases of partial core meltdowns we have now seen (the Three Mile Island reactor and the three Fukushima reactors), the zicronium fuel rod c
umm, not quite the simple (Score:2)
It was the tsunami that removed there ability to use the pumps. And crack does not equal meltdown.
It's not good, but it is critical to be as factual accurate as possible. To many emotional and political crap mixed in.
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The primary reason this happened was that the coolant pumps (and diesel engines powering them) stopped.
Earthquake pretty much forces the huge, massive and ultra-precise steam turbines of the power plant to stop - these things require micrometer precision while in operation, so leaving them running is not an option - as effect primary power source of all systems is gone. Instead, backup power kicks in, diesel generators power up the coolant pumps and keep the core cool. But diesel engines need lots of air an
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Always responding to the last disaster...
And, FYI, primary coolant *does* become radioactive in normal circumstances. That's why you need a secondary coolant loop.
Re:No. (Score:5, Insightful)
Exactly. Nuclear energy is safe. Every accident that ever happened is just a unique occurrence that could NEVER happen in *insert country of residence*. And when it's going to happen anyway, it's the fault of anti-nuke activists because they wouldn't let us build new and improved reactors. We would have totally built those despite the massive profit margins we have with the old ones. Honest!
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I know Americans aren't very familiar with good regulation, but geez.
Your argument amounts to, 'because it's financially preferable to keep old nukes running, we can't trust government to make sure new, safer ones are built'.
So, are you saying that nothing potentially dangerous should be built unless there will always be a financial incentive for people to build safer versions all the time?
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Ok, so where are all the newer, safer reactors? We have a government. According to your hypothesis they should have replaced all the old, dangerous reactors (many of which are beyond their origional design life). That simply hasn't happened.
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Saints don't let saints post on Facebook
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The mods are right. The impression that it was only earthquake was in my head only. Only information about emergency pumps not being able to pump cooler for enough time before restoring the main power lodged in my brain. Somehow I missed what Wikipedia says about it, that is some of emergency pumps were flooded by tsunami and were not operational.
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Thorium reactors wouldn't have been affected by an earthquake either. Their inherent safety, the abundance of reactor material and the cost effectiveness totally trumps existing nuclear designs as well as solar and wind power for ultimate sustainability.
Except for the fact that commercial Thorium cycle reactors don't exist just yet - it's a great idea.
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As though earthquakes and tsunamis are the only kind of natural or manmade disasters, though. I'm sure there are nuclear reactors that would turn into scuba diving sites in the event of a levee failure or during a historic flood event. I'm sure an F5 tornado would have done just as good of a job taking out the generators and smashed up the spent fuel buildings quite adeptly. Heck, I wouldn't be shocked to learn that there's a reactor in a potential avalanche zone or in an area that could be destroyed by