One of the characteristic of moder reactors like EPR (Areva) is that they can self cool without external energy. one thing missing were sand filters, that are installed in french powerplant by the demand of a stubborn engineer that lobby for that desperate mitigation system. people were moaning about that being useless since no cas was probable, bu thsi engineer asked to accept that worst can hemmeps, and that reducing the catastrophe is a good idea, and it is cheap. there would have been much less radioactive leaks if used (iodium, cesium)
Fukushima could be easily avoided, with few good decisions, but one lesson is that under cataclysmic stress (they lose all they family, were afraid , stressed) you make mistakes and lose many opprtunity,... no way to change the fact that under awful stress people are not perfectly rational. another things is that ther shoudl exist robust and flexible system. the time to be able to bring sea water, as a backup solution is not acceptable... it is dirty, but should be possible. another is to accept that catastrophe happens in group (the famous blackswan/dragon king), because of correlated causes. there have bee design errors, that were identified and could have been corrected. there was bad risk assumption in the 70s (the geophysicians were convinced earthquake could not be higher that 7 because of ferquent quake in sendai zone, but recently they discovered that 25% of the displacement was not dissipated at sendai and 9 quake ver probable... they did not believe in tsunami in that zone, but recently archeologist found 300years old huge tsunami ins the zone... (source french version of Sci American)... recent data were ignored, because of cost. as usual an accumulation of many faults, errors, bad luck, ignorance, delusion.. also like in chernobyl the privatization/performance-race seems to have allowed/caused the bad behavior... (nb: in chernobyl the change of boss to put a modern performance driven manager instead of careful old executive, caused the pressure that cause the crash. in fukushima the private status of TEPCO explain the unwillingness to address problems because of costs). but in fukushima many things have been well done, avoiding death... 2012/4/2 Axil Axil <[email protected]> > After a reactor shuts down, 15% of the rated capacity of the reactor is > released as delayed heat due to the decay of short lived radioactive > byproducts. This delayed heat must be dissipated into the environment to > keep the structure of the reactor from damage. > > >
