One of the things that's probably really not helping is that the way Japanese companies handle disaster response is different from elsewhere. They aren't talking about what went wrong, other than that something HAS gone wrong, because they do not want to misspeak and report incorrect information. We will not find out what happened to the backup power systems for quite some time, more likely than not.
Everything we've heard so far, though, points towards there simply not being enough juice to help run the coolant system. There could have been some kind of catastrophic failure of the diesel backups. We simply don't know.
Fortunately, so long as they can keep the systems cool, everything will be cool in about 8 more days as far as the reactors go. Just like Three Mile Island, this is a problem related to decay heat. (As opposed to Chernobyl's pile having gone critical.) When you shut a reactor down like this, the chain reaction stops immediately, but there are still neutrons bouncing around due to the natural effects of radioactive decay, and the whole mess is still generating heat. First stage waste products of fission don't like to hang around in the normal universe for long and fairly quickly off themselves.
It takes about ten days for the decay to settle down to levels where you don't have to pump coolant around and through the vessel to keep it from melting the contents.
- Grumpy Uncle Gearhead
Everything we've heard so far, though, points towards there simply not being enough juice to help run the coolant system. There could have been some kind of catastrophic failure of the diesel backups. We simply don't know.
Fortunately, so long as they can keep the systems cool, everything will be cool in about 8 more days as far as the reactors go. Just like Three Mile Island, this is a problem related to decay heat. (As opposed to Chernobyl's pile having gone critical.) When you shut a reactor down like this, the chain reaction stops immediately, but there are still neutrons bouncing around due to the natural effects of radioactive decay, and the whole mess is still generating heat. First stage waste products of fission don't like to hang around in the normal universe for long and fairly quickly off themselves.
It takes about ten days for the decay to settle down to levels where you don't have to pump coolant around and through the vessel to keep it from melting the contents.
- Grumpy Uncle Gearhead