The article is mostly correct, but a few corrections from a nuclear engineer:
1. What he refers to as "moderator rods" are actually control rods. The term "moderator" refers to a material that is unlikely to absorb neutrons, but likely to scatter them. This helps lower the average neutron speed inside the reactor, which actually increases the fission rate. Since water serves this purpose just fine, most reactors do not have specific "moderator rods", although BWRs actually run pipes of liquid water through the fuel assemblies for additional moderation.
2. BWRs are not run all-rods-out, like he claims. BWRs are generally run with significant control rod insertion, so that the water stays liquid for a greater portion of the height of the core.
3. He doesn't quite explain that the source of the hydrogen is a replacement reaction where zirconium and water react to create zirconium oxide and hydrogen gas.
4. Xenon-135 is a fission product, not produced by neutron activation, and neutron activation of coolant is nothing to sneer at (the half-life of tritium is 12.3 years).
Also, correct me if I'm wrong, but Cs-137 has a half life of 30 years or something. It certainly does not disappear quickly. Most of the Chernobyl contamination in Sweden was from Cesium, and that made berries and reindeer (which eat lichens) unsafe to eat for many years, if not decades.
Where does the tritium come from? As I recall tritium is one proton and two neutrons. So, you are saying that one hydrogen, that is, one proton, from the water captures a neutron and becomes deuturium and then later the deuturium captures another neutron and becomes tritium? Is that correct? Net, to those two reactions have a signficant reaction rate in the context?
My high school class in Switzerland was chosen for the yearly measurement of radioactivity in the population. The graphs they showed us as intro were interesting. Basically they start in the mid-60's and were going down. The level then flatlined at zero for many years. Then Chernobyl came and was a small blip something like 5x less than the 60's level.
Turns out a complete meltdown of a civilian reactor a few thousand miles away matters less than open air explosion of multi-megaton bombs on the other side of the world, which was the cause for the 60's levels.
Not that I wish nuclear meltdown on anyone, but the above seems to me to suggest that on a worldwide scale it wouldn't have much of an impact.
Thank you for reminding us of how much of a non-event the Chernobyl accident was for you in Switzerland, a few thousand miles away. While you're at it, don't forget tell those wimps in Belarus to shut up and stop whining about this non-event.
In theory we should be more worried about the ash radiation from our coal plants (which releases a lot more, in an unregulated manner, and makes me wonder sometimes if it's a trigger for the increase in cancer in industrialized nations).
it is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the Three Mile Island incident
The writer is not an expert on earth quakes. Making such a bold claim that nothing can go wrong is plainly false. Just because they are an expert in one area, does not mean they are an expert in all areas.
There are already a number of people being treated for radiation poisoning. They have already admitted that there have been radiation releases above safe levels.
I feel sorry for the engineers working so hard to fix this, as they face the largest dangers. They are sacrificing a lot to save other people. As history tells us, in other nuclear disasters these are the first people to die from the affects. Some have already died.
A previous earthquake a few years ago caused an explosion in one of the reactors in Japan. I guess the costs and risks were weighed up - and the risks ignored. Previously the company CEO resigned because of falsified safety reports.
The costs of nuclear reactors - even if you don't factor in the costs of these disasters are higher now than other forms of cleaner energy generation. Let's use the smarter, more innovative, and safer energy solutions available today. Let's leave these 50's and 60's era shitty technology behind.
Let's use the smarter, more innovative, and safer energy solutions available today. Let's leave these 50's and 60's era shitty technology behind.
Oh, and what do you suggest? In the US, for example, we've just about dammed every river that can be dammed, and solar and wind are too expensive for wide scale deployments.
The only real alternative we have to the 20% of our energy which comes from nuclear would be to add to the 45% which comes from coal (or to the 23% from natural gas.) That would be a disaster, coal plants are far more damaging than nuclear plants are.
We should be doing the opposite. Replacing our alarmingly high coal energy usage with nuclear plants, instead. Too bad there's so much propaganda (and big-coal lobbying) against this. Nuclear is the only practical source of zero-emission energy for wide scale use.
Personally, I'd much rather live with a couple nuclear incidents than with the horrors of today's fossile fuel industries.
The Boston Globe this morning talked about people with acute radiation sickness, too. I don't know how much faith to put in that statement, but if it's true certainly the amount of radiation release is far, far greater than anything that this post envisions. In that case, he clearly can't be correct.
Wow, such a denial of reality. 'in control'? If anything I saw in the last hours, the thing is not in control. Diesel generators failed, a building exploded, core meltdowns going on, restoring of electricity failed, seawater used for cooling (how were they pumping it and are the pumps powerful enough to provide cooling over a longer period of time like days). Valves are not working, measurement of pressure is not possible, there are fears of another explosion.
The PhD from MIT failed to mention in his article, when he talks about the 3rd containment being concrete poured around the steel casing, that the reactor which caused an explosion was built prior to this 3rd containment layer being mandatory in BWR design. So, it would seem that his confidence in the 3rd containment layer preventing any melted radioactive materials from getting out should be taken with a huge grain of salt.
You will notice that Fukushima Daiichi No. 1 (which caused the hydrogen explosion to the building walls) is a BWR/3, MK-1 model reactor. From this page, http://en.wikipedia.org/wiki/BWR#Evolution_of_the_BWR, you will see the following:
The first [General Electric] series of production BWRs evolved through 6 iterative design phases, each termed BWR/1 through BWR/6. (BWR/4s, BWR/5s, and BWR/6s are the most common types in service today.) The vast majority of BWRs in service throughout the world belong to one of these design phases.
1st generation BWR : BWR/1 with Mark-1 containment.
2nd generation BWRs : BWR/2, BWR/3 and some BWR/4 with Mark-I containment. Other BWR/4, and BWR/5 with Mark-II containment.
3rd generation BWRs : BWR/6 with Mark-III containment.
So, it would seem to me, that this confirms, it was not until at least BWR/4 or above that Mark-II containment was used. I'm pretty sure this confirms there is no 3rd containment layer.
You may have noticed that they use defense-in-depth. Even though they were just hit by one of the biggest earthquakes ever and had several unthinkable things happen, there are still people inside the control room fixing it. If it were that "OUT OF CONTROL" that panic was required, they would have fled too.
Sure, the reactor may be expensive to clean up and it may be damaged enough that they'll retire it (it's a 40-year-old BWR design, after all), but years from now, we'll probably still be debating over exactly how much radiation was released, what sort, and whether it did anything. Just so you know, educated people will completely ignore alarming reports about radiation leakage that don't contain words like "Sievert." My professors would be remiss if I didn't.
But that's the problem with radiation. It's too invisible. Most causes of death can be seen and avoided. But radiation is invisible (except in a few weird circumstances) and it can linger in some cases, so people fear it as some kind of unavoidable, invisible poison.
Never mind the fact that it's all around us. Cosmic rays. Bananas. Background radiation is everywhere. It has been for your entire life and it's not going away.
I wonder if owning a Geiger counter would calm people down or just drive them away from Brazil nuts and potatoes? [1]
The reactor 3 at the first Fukushima plant is not just using Uranium. It uses MOX fuel. So what the author ('expert???') wrote is already useless, he does not even know what the reactors are using as fuel.
MOX fuel loaded into Tokyo Electric's old Fukushima reactor
Sunday 22nd August, 05:36 AM JST
FUKUSHIMA — Tokyo Electric Power Co loaded plutonium-uranium mixed oxide fuel Saturday into a reactor at its nuclear power plant in Fukushima Prefecture in preparation for the largest Japanese utility’s first plutonium-thermal power generation.
The No. 3 reactor at the Fukushima No. 1 plant would be the third in Japan to be used for the so-called pluthermal generation, but the only one among the three to have been subjected to antiaging treatment with 34 years since its launch. Pluthermal output has already begun at the No. 3 reactor of Kyushu Electric Power Co’s Genkai plant in Saga Prefecture and the No. 3 reactor of Shikoku Electric Power Co’s Ikata plant in Ehime Prefecture.
Great article. This seems to be a great story in the media because "normal people" are not as pessimistic as engineers, and see an explosion at a nuclear reactor to be something that is extremely bad and that could be ending the world soon. After all, atomic bombs are nuclear, and those are bad, right? But in reality, while not great, failures are accounted for in the design of the reactor, and can be managed.
It's sort of like driving your car into a concrete wall on the freeway. There are buckets of sand there that dissipate the energy; they get destroyed, but you and the freeway survive. This is the purpose of those sand buckets, to blow up to prevent other things from blowing up. The outer containment building is similar; it blows up, but the environment and the reactor core are still both fine. It would be better if it didn't blow up, but it is manageable because the engineers designed for that contingency.
Good for selling newspapers, but won't be ending the world just yet.
As a fellow Tokyo resident, newly-minted quake survivor, and even fellow UFC aficionado, I found this guy's reprinted letter of explanation quite comforting. We've been kind of worrying about the nuke meltdown scenarios, and wondering if maybe we should find some pretext for a quick trip abroad in the next couple days.
And so I read this post, and nodded, and though 'Hmm, ok, good... OK, sounds reasonable. Oh, I see, great!'
And then I got to the end, and some little circuit in my brain switched on, and I realized I felt just a little bit too comforted.
As if this post, from a first-time blogger, might actually be the work product of some agent of the US pro-nuke consortium that's trying to get clearance (not to mention indemnification from liability) to build many billions of dollars worth of new plants in the US. Or, perhaps more plausibly, merely the comforting words of a family friend trying to reassure people who weren't really in a position to do much about things in any case. And whose dad works in the nuke industry, with whatever subconscious bias that might convey.
But hey, fuck it: taking that article at face value will make it easier to sleep tonight, so until morning at least I think I'll try to do that. So thanks for posting it!
There is a reason I feel much relieved after reading this. Pretty much everything I've read so far implied that once there is a meltdown, all bets are off. We'll have radioactive material boiling in open air, and all the "good" things that come with it. Which sounded very suspicious to me... I mean, isn't containment designed to prevent exactly that? Once the fuel melts, it just makes a hole on the bottom of the containment and pools on the floor? So for me, the money shot was here:
> For that purpose, a large and thick concrete basin is cast under the pressure vessel (the second containment), which is filled with graphite, all inside the third containment. This is the so-called “core catcher”. If the core melts and the pressure vessel bursts (and eventually melts), it will catch the molten fuel and everything else. It is built in such a way that the nuclear fuel will be spread out, so it can cool down.
edit: Plus reading about INES, there was a British plant that had 5 (five) level 4 incidents in 25 years, and a partial core meltdown at a French plant. And many more.
>So, ignore the independent media and get all of your information from pro-nuclear lobbies?
The msm usually doesn't have any idea what they're talking about when they report on computer related issues, why do you expect them to be any better when it comes to nuclear power?
BraveNewClimate is definitely an advocacy site, but I think it's unfair to call the guy a lobbyist. Your own link says he's a climate scientist, and doesn't make any claims that he has financial ties to the nuclear industry.
The more I read about climate change and nuclear energy, the more pro-nuke I am. If I start writing up what I've learned on my blog, would you call me a lobbyist too?
I'm shocked, how can such a lobbyist piece be high-rated at Hacker News. I though the community would be more critical towards news in general.
There are several factual errors (so much I don't know where to start), just check the press releases from TEPCO, the public statements of the Japanese Government and other public available information (e.g. http://www2.jnes.go.jp/atom-db/en/trouble/individ/power/j/j2... )
The author does not know what he is talking about, his phD. won't help him there. (Everybody clear in their mind should wonder why smb. would start a piece with "phD. Scientist" I'm working in academia and I never mentioned my degree in any post here or elsewhere, because I want that my arguments convince and not my degree) It's the first blog-post of smb.
who's linking just to nuclear energy lobbyist pages (telling you to prefer them over "standard media") and everybody starts up-voting the piece and down-voting negative and critical comments?
I suppose that my fears for this particular situation are mostly allayed. But I think that's only the tip of the iceberg.
In the face of the world's need for energy, nuclear power is the only viable option that is available today. I wonder how much this incident is going to weigh against using that option?
The power plants in operation today use technology that's quite obsolete. The design of the older plants is an historical accident. Because of the war-driven necessity of developing nuclear technology for weapons, the understanding of the technology that informed the currently-operational reactors was largely bomb-centric. But we know better today, there exists designs for reactors that are orders of magnitude safer, both in terms of operational dangers as well as its waste byproducts.
I'm afraid that sound-byte driven media and activists who aren't willing to evaluate newer ideas will cause such prejudice that newer, better technology will never see the light of day, and thus we'll see worse environmental problems (or economic problems) because our current energy problems can't be fixed otherwise.
> ...nuclear power is the only viable option that is available today...
Nuclear power in itself is unlikely to solve our energy problems. It is only a part of the solution. We will not be able to supply the world with enough energy using nuclear power alone given the length of time it takes to design, approve, build, and certify a nuclear power station.
Strange... I didn't see this story on the new page and submitted after you and it posted a new version instead of auto-voting for yours. I didn't think HN would do that. Going to go delete that version now…
This is the most coherent description of the issues and events that I've read (and I've read a few). I learned a lot about BWR nuclear plants.
Some people here in Tokyo are starting to get very nervous and mostly that comes because nuclear power is so damn confusing. Understanding it can help you keep your wits. They are showing documentaries on Japanese TV about the cause of the tsunami right now but I think they should be showing "Nuclear Power 101" instead.
Edit: Another thing that is causing a lot of confusion is that there are two power plants that were affected (daiichi and daini) and each plant has multiple reactors. They were both operated by TEPCO as well so the press releases are coming from the same place. Keeping track of all of them is a bit confusing. This article is mostly about the most serious problem which is reactor one at daiichi.
Staying cool on the other side of the globe is far easier than living right next to it. So kudos!
It is hard to understand the technology behind it. Harder than just burst into cunfusion and condemning things. Every time I tried to get to know more about how nuclear reactors work, the more I found out, the more it calmed me down.
He says that even in the case of a total meltdown (which hopefully will not happen in Fukushima) we will be save because everything will be contained in the third containment.
What I don't get is how cooling is supposed to happen in this case. I think they still would have to pump sea water into the containment which would then get contaminated not only by neutron activation but also with Uranium, Cesium, Iodine etc.
What happens to the seawater then: Will it be released into the environment? Is it in liquid form or will it be released as steam?
I've been telling people this all day, but it's great to have a PhD confirm it.
BTW, with Chernobyl the control rods were not able to be inserted all the way, which is one of the main reasons it was so bad - the chain reaction never stopped, and the heat just kept building up.
It would be better if his PhD or his research were in a domain anywhere close to what he is talking about. Also, it would be better if the information he has where not only what is said in the news... People knowing what they talk about are really, really scared about the nuclear situation in Japan right now.
The description he makes of how a plant works is nice, but being "a PhD" in an unrelated field doesn't mean much to me... if he had been a nuclear physicist with nice publications or nuclear engineer working at the xxx plant AND if he had access to additional information on what it's really happening/ed i would have cared more for his conclusions...
Looking at the comments [1] (guy from Japanese Atomic Energy Agency) it even seems that he is describing a different configuration of nuclear plant (newer,safer).
Ive asked my Nuclear Fusion expert mate on this article and others, waiting to hear back and Ill post his response. He is currently working at the Department of Nuclear, Plasma and Radiological engineering at a US University, so I figure he'll know a thing or two.
Here's TLDR version: (1) the steam released has radioactivity lasting on the order of seconds, (2) if/when meltdown occurs, cesium/iodine radionuclides can exist in the steam but are apparently blown out to sea away from Japan, and (3) with the exception of controlled steam releases, a steel containment surrounding the core & related components will absolutely contain 100% of worst-case scenarios, meltdowns, etc.
At least that's how I understood it. Not an expert so I have no idea how much of it is true or not.
I am thinking about California's nuclear power plants. I figure that we will learn reasonable and effective ways to make them safer, perhaps ensure the diesel back generators are safe from a Tsunami. And this will cost money that we should spend. It is not like the California budget is swimming with money.
People talked about how strong this earthquake was, and it was strong, but the epicenter missed the power plants by quite a distance. Then we will get a surprise when a much smaller quake his one much worse.
This is a nice article, however:
Breaking News:
"U.S. Seventh Fleet moves ships, planes away from quake-hit Japanese nuclear plant after discovering low-level radioactive contamination"
Interesting also that in the INES pdf on that site, the requirement for INES4 is at least one death from radiation. Perhaps the declaration of INES level four was in error, or the requirement is not strict.
Another interesting link just found: http://en.wikipedia.org/wiki/List_of_civilian_nuclear_accide...
The light from the Sun that strikes this planet, (the largest fusion based nuclear reactor in the Solar System) produces more energy in one day than all the nuclear, oil, or coal based power plants on the planet.
One has to wonder why governments insist on building poisonous, fragile, radioactive generators on earth, when we can safely harness solar, wind, and wave energies without such horrifying risk.
Will it be the lack of common sense that is cited as the primary downfall of civilization when we are long gone, due to our less than intelligent decisions about energy? Who among us wishes to have children play along the Gulf coast of the United States this summer? Oil illness anyone? Or along the coast of Northern Japan for the next 25,000 years or so...
Does anyone seriously believe that a "shoot for the moon" style campaign like the one we held to create nuclear power plants, would not result in workable alternative energy programs?
One point is certain. Earthquakes WILL continue to happen.
One other point is certain. Nuclear energy is inherently dangerous. You can only minimize the chance of catastrophic failure. Not eliminate it. And once the genie is out of the containment vessel, the penalty last 25,000+ years.
No amount of carefully considered analysis changes the science of this issue. It's time to give alternative energy solutions the same level of serious treatment we have lent to coal and nuclear systems or prepare for a future where meltdowns and frantic efforts to prevent them are more common place.
A future where more than a few locations become permanent exclusion zones for thousands of years. A future for your children where the increased incidence of cancer and mutation is part of every day living.
Or not if we come to our senses and throw every effort into fully developing alternate energy systems. We have a fusion reactor handy just 93 million miles away with billions of years of energy to come. Lets use it.
The reason people build power stations is that density of energy matters, not just quantity.
Sure, we can replace our current energy sources with solar + wind + wave.
What fraction of coastline needs to be covered with wave-driven generators, and what fraction of Earth's land area needs to be covered with solar or wind farms to get to our current energy generation levels? Last I saw the numbers for the US they weren't pretty.
Just to run the numbers for the US, average insolation for the Earth is 250W/m^2 according to <http://en.wikipedia.org/wiki/Insolation>. That's for the whole spectrum, not just whatever solar cells can actually use.
The land area of the US according to <http://en.wikipedia.org/wiki/United_States>; is a shade under 1e13m^2. That gives us a total of about 2.5e15W for solar power for the continental US, assuming your solar cells are amazing and have 100% efficiency across the full electromagnetic spectrum (as in, you've done an "Apollo Program" for solar cells and had amazing results).
Energy consumption in the US 5 years ago was about 29e15PWh/year, so about 3.3e12W.
So we'd need to entirely cover about .13% of the land area of the US in solar cells to get the amount of power we were using 5 years ago. We're using more now, of course.
That's about the area of Connecticut.
Now what's the useful life of solar cells? How high can we sensible expect to get it? How do we plan to handle the fact that the generation is ... very variable? How close to 100% efficiency do we think we can actually get solar cells? How noxious is the production process for these solar cells you'll have to be cranking out continuously to replace the failing ones, and where do you plan to locate it?
> Does anyone seriously believe that a "shoot for the moon"
> style campaign like the one we held to create nuclear
> power plants, would not result in workable alternative
> energy programs?
Yes. I don't think such a campaign would get us to the point where we could use any combination of wind, solar, wave for baseline power.
> Nuclear energy is inherently dangerous.
So are solar cell production facilities. So is swimming, for that matter; the question is one of probabilities.
> the penalty last 25,000+ years.
How long does the "penalty" for a serious chemical spill last?
> No amount of carefully considered analysis changes the
> science of this issue.
> The light from the Sun that strikes this planet, (the largest fusion based nuclear reactor in the Solar System) produces more energy in one day than all the nuclear, oil, or coal based power plants on the planet.
[+] [-] neutronicus|15 years ago|reply
1. What he refers to as "moderator rods" are actually control rods. The term "moderator" refers to a material that is unlikely to absorb neutrons, but likely to scatter them. This helps lower the average neutron speed inside the reactor, which actually increases the fission rate. Since water serves this purpose just fine, most reactors do not have specific "moderator rods", although BWRs actually run pipes of liquid water through the fuel assemblies for additional moderation.
2. BWRs are not run all-rods-out, like he claims. BWRs are generally run with significant control rod insertion, so that the water stays liquid for a greater portion of the height of the core.
3. He doesn't quite explain that the source of the hydrogen is a replacement reaction where zirconium and water react to create zirconium oxide and hydrogen gas.
4. Xenon-135 is a fission product, not produced by neutron activation, and neutron activation of coolant is nothing to sneer at (the half-life of tritium is 12.3 years).
[+] [-] lutorm|15 years ago|reply
[+] [-] Wientje|15 years ago|reply
[+] [-] pdenya|15 years ago|reply
[+] [-] NY_USA_Hacker|15 years ago|reply
[+] [-] benohear|15 years ago|reply
Turns out a complete meltdown of a civilian reactor a few thousand miles away matters less than open air explosion of multi-megaton bombs on the other side of the world, which was the cause for the 60's levels.
Not that I wish nuclear meltdown on anyone, but the above seems to me to suggest that on a worldwide scale it wouldn't have much of an impact.
[+] [-] vdbnnss|15 years ago|reply
[+] [-] ck2|15 years ago|reply
http://en.wikipedia.org/wiki/Fossil_fuel_power_station#Radio...
it is estimated that during 1982, US coal burning released 155 times as much uncontrolled radioactivity into the atmosphere as the Three Mile Island incident
[+] [-] ugh|15 years ago|reply
[+] [-] wtn|15 years ago|reply
[+] [-] illumen|15 years ago|reply
There are already a number of people being treated for radiation poisoning. They have already admitted that there have been radiation releases above safe levels.
I feel sorry for the engineers working so hard to fix this, as they face the largest dangers. They are sacrificing a lot to save other people. As history tells us, in other nuclear disasters these are the first people to die from the affects. Some have already died.
A previous earthquake a few years ago caused an explosion in one of the reactors in Japan. I guess the costs and risks were weighed up - and the risks ignored. Previously the company CEO resigned because of falsified safety reports.
The costs of nuclear reactors - even if you don't factor in the costs of these disasters are higher now than other forms of cleaner energy generation. Let's use the smarter, more innovative, and safer energy solutions available today. Let's leave these 50's and 60's era shitty technology behind.
[+] [-] SeoxyS|15 years ago|reply
Oh, and what do you suggest? In the US, for example, we've just about dammed every river that can be dammed, and solar and wind are too expensive for wide scale deployments.
The only real alternative we have to the 20% of our energy which comes from nuclear would be to add to the 45% which comes from coal (or to the 23% from natural gas.) That would be a disaster, coal plants are far more damaging than nuclear plants are.
We should be doing the opposite. Replacing our alarmingly high coal energy usage with nuclear plants, instead. Too bad there's so much propaganda (and big-coal lobbying) against this. Nuclear is the only practical source of zero-emission energy for wide scale use.
Personally, I'd much rather live with a couple nuclear incidents than with the horrors of today's fossile fuel industries.
[+] [-] lutorm|15 years ago|reply
[+] [-] nitrogen|15 years ago|reply
I agree. Let's replace all ~40-year-old reactors (like the ones breaking down in Japan) with modern, fail-safe nuclear designs.
[+] [-] lispm|15 years ago|reply
Two reactors are still OUT OF CONTROL.
One of them is even using Plutonium in its fuel. German news about that: http://www.spiegel.de/wissenschaft/technik/0,1518,750668,00....
Whether the containment will work as designed is unknown.
Fukushima II, the other plant has cooling problems, too.
Now there has been an alarm of higher radiation at the Onagawa plant.
German source: http://www.spiegel.de/panorama/0,1518,750637,00.html
[+] [-] illumin8|15 years ago|reply
Updating with more information: Please see this list of BWR reactors throughout the world: http://en.wikipedia.org/wiki/List_of_boiling_water_reactors
You will notice that Fukushima Daiichi No. 1 (which caused the hydrogen explosion to the building walls) is a BWR/3, MK-1 model reactor. From this page, http://en.wikipedia.org/wiki/BWR#Evolution_of_the_BWR, you will see the following:
The first [General Electric] series of production BWRs evolved through 6 iterative design phases, each termed BWR/1 through BWR/6. (BWR/4s, BWR/5s, and BWR/6s are the most common types in service today.) The vast majority of BWRs in service throughout the world belong to one of these design phases.
1st generation BWR : BWR/1 with Mark-1 containment.
2nd generation BWRs : BWR/2, BWR/3 and some BWR/4 with Mark-I containment. Other BWR/4, and BWR/5 with Mark-II containment.
3rd generation BWRs : BWR/6 with Mark-III containment.
So, it would seem to me, that this confirms, it was not until at least BWR/4 or above that Mark-II containment was used. I'm pretty sure this confirms there is no 3rd containment layer.
[+] [-] Natsu|15 years ago|reply
You may have noticed that they use defense-in-depth. Even though they were just hit by one of the biggest earthquakes ever and had several unthinkable things happen, there are still people inside the control room fixing it. If it were that "OUT OF CONTROL" that panic was required, they would have fled too.
Sure, the reactor may be expensive to clean up and it may be damaged enough that they'll retire it (it's a 40-year-old BWR design, after all), but years from now, we'll probably still be debating over exactly how much radiation was released, what sort, and whether it did anything. Just so you know, educated people will completely ignore alarming reports about radiation leakage that don't contain words like "Sievert." My professors would be remiss if I didn't.
But that's the problem with radiation. It's too invisible. Most causes of death can be seen and avoided. But radiation is invisible (except in a few weird circumstances) and it can linger in some cases, so people fear it as some kind of unavoidable, invisible poison.
Never mind the fact that it's all around us. Cosmic rays. Bananas. Background radiation is everywhere. It has been for your entire life and it's not going away.
I wonder if owning a Geiger counter would calm people down or just drive them away from Brazil nuts and potatoes? [1]
[1] https://secure.wikimedia.org/wikipedia/en/w/index.php?title=...
[+] [-] lispm|15 years ago|reply
Japan Today:
http://www.japantoday.com/category/technology/view/mox-fuel-...
From August last year:
MOX fuel loaded into Tokyo Electric's old Fukushima reactor Sunday 22nd August, 05:36 AM JST
FUKUSHIMA — Tokyo Electric Power Co loaded plutonium-uranium mixed oxide fuel Saturday into a reactor at its nuclear power plant in Fukushima Prefecture in preparation for the largest Japanese utility’s first plutonium-thermal power generation.
The No. 3 reactor at the Fukushima No. 1 plant would be the third in Japan to be used for the so-called pluthermal generation, but the only one among the three to have been subjected to antiaging treatment with 34 years since its launch. Pluthermal output has already begun at the No. 3 reactor of Kyushu Electric Power Co’s Genkai plant in Saga Prefecture and the No. 3 reactor of Shikoku Electric Power Co’s Ikata plant in Ehime Prefecture.
[+] [-] borism|15 years ago|reply
[+] [-] jrockway|15 years ago|reply
It's sort of like driving your car into a concrete wall on the freeway. There are buckets of sand there that dissipate the energy; they get destroyed, but you and the freeway survive. This is the purpose of those sand buckets, to blow up to prevent other things from blowing up. The outer containment building is similar; it blows up, but the environment and the reactor core are still both fine. It would be better if it didn't blow up, but it is manageable because the engineers designed for that contingency.
Good for selling newspapers, but won't be ending the world just yet.
[+] [-] jshen|15 years ago|reply
How confident are you in that statement?
[+] [-] veidr|15 years ago|reply
And so I read this post, and nodded, and though 'Hmm, ok, good... OK, sounds reasonable. Oh, I see, great!'
And then I got to the end, and some little circuit in my brain switched on, and I realized I felt just a little bit too comforted.
As if this post, from a first-time blogger, might actually be the work product of some agent of the US pro-nuke consortium that's trying to get clearance (not to mention indemnification from liability) to build many billions of dollars worth of new plants in the US. Or, perhaps more plausibly, merely the comforting words of a family friend trying to reassure people who weren't really in a position to do much about things in any case. And whose dad works in the nuke industry, with whatever subconscious bias that might convey.
But hey, fuck it: taking that article at face value will make it easier to sleep tonight, so until morning at least I think I'll try to do that. So thanks for posting it!
[+] [-] radu_floricica|15 years ago|reply
> For that purpose, a large and thick concrete basin is cast under the pressure vessel (the second containment), which is filled with graphite, all inside the third containment. This is the so-called “core catcher”. If the core melts and the pressure vessel bursts (and eventually melts), it will catch the molten fuel and everything else. It is built in such a way that the nuclear fuel will be spread out, so it can cool down.
edit: Plus reading about INES, there was a British plant that had 5 (five) level 4 incidents in 25 years, and a partial core meltdown at a French plant. And many more.
[+] [-] miles|15 years ago|reply
"If you want to stay informed, please forget the usual media outlets and consult the following websites"
and goes on to list 3 nuclear lobbying websites.
So, ignore the independent media and get all of your information from pro-nuclear lobbies?
More: https://morgsatlarge.wordpress.com/2011/03/13/why-i-am-not-w...
[+] [-] samlevine|15 years ago|reply
The msm usually doesn't have any idea what they're talking about when they report on computer related issues, why do you expect them to be any better when it comes to nuclear power?
[+] [-] DennisP|15 years ago|reply
The more I read about climate change and nuclear energy, the more pro-nuke I am. If I start writing up what I've learned on my blog, would you call me a lobbyist too?
[+] [-] kgarten|15 years ago|reply
There are several factual errors (so much I don't know where to start), just check the press releases from TEPCO, the public statements of the Japanese Government and other public available information (e.g. http://www2.jnes.go.jp/atom-db/en/trouble/individ/power/j/j2... )
The author does not know what he is talking about, his phD. won't help him there. (Everybody clear in their mind should wonder why smb. would start a piece with "phD. Scientist" I'm working in academia and I never mentioned my degree in any post here or elsewhere, because I want that my arguments convince and not my degree) It's the first blog-post of smb. who's linking just to nuclear energy lobbyist pages (telling you to prefer them over "standard media") and everybody starts up-voting the piece and down-voting negative and critical comments?
I thought hacker news was better.
[+] [-] innes|15 years ago|reply
[+] [-] CWuestefeld|15 years ago|reply
In the face of the world's need for energy, nuclear power is the only viable option that is available today. I wonder how much this incident is going to weigh against using that option?
The power plants in operation today use technology that's quite obsolete. The design of the older plants is an historical accident. Because of the war-driven necessity of developing nuclear technology for weapons, the understanding of the technology that informed the currently-operational reactors was largely bomb-centric. But we know better today, there exists designs for reactors that are orders of magnitude safer, both in terms of operational dangers as well as its waste byproducts.
I'm afraid that sound-byte driven media and activists who aren't willing to evaluate newer ideas will cause such prejudice that newer, better technology will never see the light of day, and thus we'll see worse environmental problems (or economic problems) because our current energy problems can't be fixed otherwise.
[+] [-] ANH|15 years ago|reply
Nuclear power in itself is unlikely to solve our energy problems. It is only a part of the solution. We will not be able to supply the world with enough energy using nuclear power alone given the length of time it takes to design, approve, build, and certify a nuclear power station.
The Sun is by far our greatest source of energy.
Have a look at http://en.wikipedia.org/wiki/World_energy_resources_and_cons...
[+] [-] nitrogen|15 years ago|reply
[+] [-] po|15 years ago|reply
This is the most coherent description of the issues and events that I've read (and I've read a few). I learned a lot about BWR nuclear plants.
Some people here in Tokyo are starting to get very nervous and mostly that comes because nuclear power is so damn confusing. Understanding it can help you keep your wits. They are showing documentaries on Japanese TV about the cause of the tsunami right now but I think they should be showing "Nuclear Power 101" instead.
Edit: Another thing that is causing a lot of confusion is that there are two power plants that were affected (daiichi and daini) and each plant has multiple reactors. They were both operated by TEPCO as well so the press releases are coming from the same place. Keeping track of all of them is a bit confusing. This article is mostly about the most serious problem which is reactor one at daiichi.
[+] [-] woodpanel|15 years ago|reply
It is hard to understand the technology behind it. Harder than just burst into cunfusion and condemning things. Every time I tried to get to know more about how nuclear reactors work, the more I found out, the more it calmed me down.
[+] [-] weinzierl|15 years ago|reply
What I don't get is how cooling is supposed to happen in this case. I think they still would have to pump sea water into the containment which would then get contaminated not only by neutron activation but also with Uranium, Cesium, Iodine etc.
What happens to the seawater then: Will it be released into the environment? Is it in liquid form or will it be released as steam?
[+] [-] ars|15 years ago|reply
Water pretty much can't get radioactive. (For more than a few minutes.)
The longest radioactive oxygen you can make in a reactor has a half life of 26 seconds.
For hydrogen, deuterium is not radioactive, and tritium can't be made in a light water reactor.
So water effectively can't get radioactive.
[+] [-] ars|15 years ago|reply
I've been telling people this all day, but it's great to have a PhD confirm it.
BTW, with Chernobyl the control rods were not able to be inserted all the way, which is one of the main reasons it was so bad - the chain reaction never stopped, and the heat just kept building up.
[+] [-] secretasiandan|15 years ago|reply
http://lean.mit.edu/about/lai-structure/faculty-researchers-...
Where does he get his expertise in nuclear reactors? According to the article, his father.
"He is a PhD Scientist, whose father has extensive experience in Germany’s nuclear industry"
[+] [-] p4bl0|15 years ago|reply
[+] [-] drtse4|15 years ago|reply
[1] https://morgsatlarge.wordpress.com/2011/03/13/why-i-am-not-w...
Check out the other comments from Daniel on that post for additional info on procedures being put in action by the jp government.
[+] [-] locusm|15 years ago|reply
[+] [-] hammock|15 years ago|reply
At least that's how I understood it. Not an expert so I have no idea how much of it is true or not.
[+] [-] artsrc|15 years ago|reply
People talked about how strong this earthquake was, and it was strong, but the epicenter missed the power plants by quite a distance. Then we will get a surprise when a much smaller quake his one much worse.
[+] [-] unknown|15 years ago|reply
[deleted]
[+] [-] adlep|15 years ago|reply
I suggest you start worrying. More info here: http://www.nytimes.com/2011/03/14/world/asia/14plume.html
[+] [-] radu_floricica|15 years ago|reply
[+] [-] eliasmacpherson|15 years ago|reply
[+] [-] catfish|15 years ago|reply
One has to wonder why governments insist on building poisonous, fragile, radioactive generators on earth, when we can safely harness solar, wind, and wave energies without such horrifying risk.
Will it be the lack of common sense that is cited as the primary downfall of civilization when we are long gone, due to our less than intelligent decisions about energy? Who among us wishes to have children play along the Gulf coast of the United States this summer? Oil illness anyone? Or along the coast of Northern Japan for the next 25,000 years or so...
Does anyone seriously believe that a "shoot for the moon" style campaign like the one we held to create nuclear power plants, would not result in workable alternative energy programs?
One point is certain. Earthquakes WILL continue to happen.
One other point is certain. Nuclear energy is inherently dangerous. You can only minimize the chance of catastrophic failure. Not eliminate it. And once the genie is out of the containment vessel, the penalty last 25,000+ years.
No amount of carefully considered analysis changes the science of this issue. It's time to give alternative energy solutions the same level of serious treatment we have lent to coal and nuclear systems or prepare for a future where meltdowns and frantic efforts to prevent them are more common place.
A future where more than a few locations become permanent exclusion zones for thousands of years. A future for your children where the increased incidence of cancer and mutation is part of every day living.
Or not if we come to our senses and throw every effort into fully developing alternate energy systems. We have a fusion reactor handy just 93 million miles away with billions of years of energy to come. Lets use it.
[+] [-] bzbarsky|15 years ago|reply
Sure, we can replace our current energy sources with solar + wind + wave.
What fraction of coastline needs to be covered with wave-driven generators, and what fraction of Earth's land area needs to be covered with solar or wind farms to get to our current energy generation levels? Last I saw the numbers for the US they weren't pretty.
Just to run the numbers for the US, average insolation for the Earth is 250W/m^2 according to <http://en.wikipedia.org/wiki/Insolation>. That's for the whole spectrum, not just whatever solar cells can actually use.
The land area of the US according to <http://en.wikipedia.org/wiki/United_States>; is a shade under 1e13m^2. That gives us a total of about 2.5e15W for solar power for the continental US, assuming your solar cells are amazing and have 100% efficiency across the full electromagnetic spectrum (as in, you've done an "Apollo Program" for solar cells and had amazing results).
Energy consumption in the US 5 years ago was about 29e15PWh/year, so about 3.3e12W.
So we'd need to entirely cover about .13% of the land area of the US in solar cells to get the amount of power we were using 5 years ago. We're using more now, of course.
That's about the area of Connecticut.
Now what's the useful life of solar cells? How high can we sensible expect to get it? How do we plan to handle the fact that the generation is ... very variable? How close to 100% efficiency do we think we can actually get solar cells? How noxious is the production process for these solar cells you'll have to be cranking out continuously to replace the failing ones, and where do you plan to locate it?
> Does anyone seriously believe that a "shoot for the moon" > style campaign like the one we held to create nuclear > power plants, would not result in workable alternative > energy programs?
Yes. I don't think such a campaign would get us to the point where we could use any combination of wind, solar, wave for baseline power.
> Nuclear energy is inherently dangerous.
So are solar cell production facilities. So is swimming, for that matter; the question is one of probabilities.
> the penalty last 25,000+ years.
How long does the "penalty" for a serious chemical spill last?
> No amount of carefully considered analysis changes the > science of this issue.
This much we agree on. ;)
[+] [-] technomancy|15 years ago|reply
I live in Seattle, you insensitive clod.
[+] [-] artursapek|15 years ago|reply