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I always thought that the reactors survived a tsunami and a earthquake at the same time was pretty good. Damaged but still intact, I do think it will take awhil

I always thought that the reactors survived a tsunami and a earthquake at the same time was pretty good. Damaged but still intact, I do think it will take awhile for the whole picture to emerge on what took place. It seems most of the news about the nuclear hazards are an echo chamber so there might be some real danger. Most of the safety systems were wiped out and it's still standing? I had imaged the reactor turning into a roman candle launching fuel rods all over the place. The entire picture has yet to emerge and yet people are talking about it like the show is over. But then again most people commenting about the situation are pretty far away from Japan. Myself: I'm sitting in California. I'm sure if the San Onfre Plant started venting a small amount of radiation I would get a little edgy including a shift in perspective An out of control/damaged nuclear plant is still a out of control/damaged nuclear plant. Radiation leakage or no radiation leakage. I would be mad if any radiation came my way due to someone cutting corners or just not caring, no matter the dosage.

jacques_chester 16y ago
> An out of control/damaged nuclear plant is still a out of control/damaged nuclear plant. Indeed. To borrow a meme from elsewhere, TRWTF is that the design requires active cooling for safe operation. Fukushima has proved that any safety system requiring active operation will inevitably fail. The worst failure mode is meltdown, which the containment vessel would catch as the final line of defence (a la Three Mile Island), but it shouldn't have gotten this far in the first place. That said, Fukushima is a 40-year-old design. Hopefully it'll be replaced with something with more passive safety.
- wiredfool 16y ago
  It's a 40 year old plant with a 50 year old design that was done before Plate Tectonics and subduction zones were accepted theories. (ca late 60's for those theories) And, despite fudged safety records, losing all cooling power, and having a 9.0 quake and a 12 m tsunami hit it, it still hasn't killed anyone. That's pretty good. It's bad that it's going to cost billions of dollars to secure, but in the scope of the overall disaster, it's a small percentage. In 20 years, there's a good chance that people will be saying "I can't believe that they kept building gas and coal plants, look at what it's done to the environment."
  - orblivion 16y ago
    I hate to be pedantic, didn't it at least kill a couple workers?
    - wiredfool 16y ago
      A crane fell. Not radiation. (unless there's been a recent change)
- neutronicus 16y ago
  TRWTF is that the design requires active cooling for safe operation. It's less of a WTF than you think. You have to read the fine print of the supposedly "passively cooled" designs. The Westinghouse AP1000, for instance, is "passively cooled" in the instance of a scram, but only for 72 hours. Although this is about 9 times as long as the Japanese cooling systems ran on batteries, it is significantly less time than the reactors have been without power. The fact is that a lot of decay heat is dumped into that system in a pretty short time, and you're going to need mass flows (read: pumps) if you're going to reject it all safely. (I suppose a molten salt reactor might allow you to get more creative with mass transport, since you can conceivably move the fuel somewhere else, but those designs are a long way off, and I'm sure they come with their own unique hazards)
  - jacques_chester 16y ago
    Thanks, I didn't know that about the 3+ systems. However my understanding of Gen 4 systems is that passive cooling is the central design element. I mean, it's inefficient, but when you're talking about nuclear it's not as though source energy is hard to come by.
    - neutronicus 16y ago
      "Passive cooling" are words that people like to hear, so everyone's going to tell you that their favorite Gen IV is "passively cooled", but one has to approach these claims with a certain level of realism. I mean, the reactor's going to be producing about 1% of rated thermal power for a few days after shutdown, so 36 MW. The heat of vaporization of water is about 3 MJ/kg (heat of vaporization is more important than heat capacity, so we'll just use that). That means that the fuel inside a 1 GWe nuclear reactor, a day or two after shutdown, can boil 12 kg of water in a second. This is a fundamental property of nuclear reactors - no reactor design is going to make decay heat disappear. So I would be skeptical of designs that claim to be "passively cooled". What they mean is "passively cooled for a while", which is an important engineering achievement that I don't want to trivialize at all - I just think it puts the current designs a little in perspective, since some people apparently believe that you can scram a gen 4 reactor, go on a luxury 7-night cruise, and then deal with at your liesure, which isn't true - you've got to find a way to get water in there (or whatever), you just have a lot more time to do so because of the passive safety systems.
- FirstHopSystems 16y ago
  Agreed, There is always going to be risk involved with nuclear power. Your trying to contain something that will kill you if it has the chance. During a nuclear emergency they should release laughing babies and kittens. Only one of the two might try to kill you. The only problem is you can't tell which one. Upside: Laughing Babies and Kittens!!! I could only theorize you could use some sort of backup turbine built into the containment vessel. Then again if your not sure what kind of damage is done having something that is self powering might not be a good idea if it's out of control.
lispm 16y ago
you are watching a car which has been pushed over the cliff and while it is falling, you are telling us that the car is still looking fine...
- FirstHopSystems 16y ago
  That's what I was trying to say, Most people are basing judgment of the situation from a echo chamber of media outlets. There might be much more going on hazard-wise than just the core overheating. The overheating is main stage right now from all the tension it has caused.

jacques_chester 16y ago

> An out of control/damaged nuclear plant is still a out of control/damaged nuclear plant. Indeed. To borrow a meme from elsewhere, TRWTF is that the design requires active cooling for safe operation. Fukushima has proved that any safety system requiring active operation will inevitably fail. The worst failure mode is meltdown, which the containment vessel would catch as the final line of defence (a la Three Mile Island), but it shouldn't have gotten this far in the first place. That said, Fukushima is a 40-year-old design. Hopefully it'll be replaced with something with more passive safety.

wiredfool 16y ago
It's a 40 year old plant with a 50 year old design that was done before Plate Tectonics and subduction zones were accepted theories. (ca late 60's for those theories) And, despite fudged safety records, losing all cooling power, and having a 9.0 quake and a 12 m tsunami hit it, it still hasn't killed anyone. That's pretty good. It's bad that it's going to cost billions of dollars to secure, but in the scope of the overall disaster, it's a small percentage. In 20 years, there's a good chance that people will be saying "I can't believe that they kept building gas and coal plants, look at what it's done to the environment."
- orblivion 16y ago
  I hate to be pedantic, didn't it at least kill a couple workers?
  - wiredfool 16y ago
    A crane fell. Not radiation. (unless there's been a recent change)
neutronicus 16y ago
TRWTF is that the design requires active cooling for safe operation. It's less of a WTF than you think. You have to read the fine print of the supposedly "passively cooled" designs. The Westinghouse AP1000, for instance, is "passively cooled" in the instance of a scram, but only for 72 hours. Although this is about 9 times as long as the Japanese cooling systems ran on batteries, it is significantly less time than the reactors have been without power. The fact is that a lot of decay heat is dumped into that system in a pretty short time, and you're going to need mass flows (read: pumps) if you're going to reject it all safely. (I suppose a molten salt reactor might allow you to get more creative with mass transport, since you can conceivably move the fuel somewhere else, but those designs are a long way off, and I'm sure they come with their own unique hazards)
- jacques_chester 16y ago
  Thanks, I didn't know that about the 3+ systems. However my understanding of Gen 4 systems is that passive cooling is the central design element. I mean, it's inefficient, but when you're talking about nuclear it's not as though source energy is hard to come by.
  - neutronicus 16y ago
    "Passive cooling" are words that people like to hear, so everyone's going to tell you that their favorite Gen IV is "passively cooled", but one has to approach these claims with a certain level of realism. I mean, the reactor's going to be producing about 1% of rated thermal power for a few days after shutdown, so 36 MW. The heat of vaporization of water is about 3 MJ/kg (heat of vaporization is more important than heat capacity, so we'll just use that). That means that the fuel inside a 1 GWe nuclear reactor, a day or two after shutdown, can boil 12 kg of water in a second. This is a fundamental property of nuclear reactors - no reactor design is going to make decay heat disappear. So I would be skeptical of designs that claim to be "passively cooled". What they mean is "passively cooled for a while", which is an important engineering achievement that I don't want to trivialize at all - I just think it puts the current designs a little in perspective, since some people apparently believe that you can scram a gen 4 reactor, go on a luxury 7-night cruise, and then deal with at your liesure, which isn't true - you've got to find a way to get water in there (or whatever), you just have a lot more time to do so because of the passive safety systems.
FirstHopSystems 16y ago
Agreed, There is always going to be risk involved with nuclear power. Your trying to contain something that will kill you if it has the chance. During a nuclear emergency they should release laughing babies and kittens. Only one of the two might try to kill you. The only problem is you can't tell which one. Upside: Laughing Babies and Kittens!!! I could only theorize you could use some sort of backup turbine built into the containment vessel. Then again if your not sure what kind of damage is done having something that is self powering might not be a good idea if it's out of control.

lispm 16y ago

you are watching a car which has been pushed over the cliff and while it is falling, you are telling us that the car is still looking fine...

FirstHopSystems 16y ago
That's what I was trying to say, Most people are basing judgment of the situation from a echo chamber of media outlets. There might be much more going on hazard-wise than just the core overheating. The overheating is main stage right now from all the tension it has caused.