The plant should have been dismantled, flooded, and buried within 24 hours of the emergency generators going down. They knew how bad it was/is, this all could have been prevented.
It is simply not possible to dismantle a nuclear reactor that close after shutdown -- the power produced by radioactive decay heat right after shutdown is in the order of 10MW, and the core is incredibly hot for weeks. If they had done everything as well as they possibly could, they would not be any closer to dismantling the plants than they are today. The best course would have been to maintain cooling so that nothing would have been damaged -- they tried this and failed. The failures in their actions are not asking for more help earlier, not in the basic course of action they took. The idea that the reactors should have been buried with 24 hours of the emergency generators going down betrays basic lack of knowledge of the facts of the situation. Should you have tried to bury a core that has been active less than a day before without considerable active cooling, it would have simply melted it's way to the water table.
The total amount of plutonium that has been released into the environment so far is minuscule. It is significant because it serves as an unmistakable indicator that the cladding for the rods has melted, meaning that should any containment fail now, the results would be catastrophic. But we knew that -- TEPCO said that the cladding was melting on 14th of March. Still, unless something unexpected and catastrophic happens now, the nuclear side of this disaster will still kill more people in Germany than Japan.
They've temporarily shut off all their nuclear plants constructed before 1980. They need to get power from somewhere, and nuclear power has the lowest number of deaths per terawatt-hour of any currently-viable competing energy source.
Coal pollutes the atmosphere and kills miners (among other things). Natural gas has an unpleasant tendency to explode during handling, and is considerably more expensive than coal. And so on.
I think that last thing is inaccurate. Because of better efficiency, simpler plant design, and no fly ash disposal natural gas generated electricity is a little cheaper at current prices. This was a surprise to me, because coal can be 15-70% the price per BTU vs natural gas (coal prices and energy density vary by region).
Nuclear may have the lowest number of deaths/power, but technically the Space Shuttle was the safest way to fly from 1977 to 1986.
I'd like to point out that even if there were a Chernobyl every two weeks, nuclear would still kill less than coal.
I'm not necessarily that pro-nuclear, I just cannot fathom why all the outrage in power production seems to be directed towards nuclear while coal, that kills ~2700 people worldwide every day is still being used.
What did I say that made you think I wasn't aware of how destructive coal generate power is? I don't need to point out why people are talking so much more about nuclear power safety than coal safety over the past month or so.
The situation in question is Merkel shutting down the 7 oldest German nuclear plants for 3 months. There will be no new clean sources of power deployed during those 3 months -- and unless there is a national campaign to reduce use starting right now in Germany, it will be mostly covered by coal.
During those 3 months, ~250 more will die to SO2 and NOx because of increased coal power production.
I'm disappointed that I was downvoted to 0 on this one. I didn't think I was overly argumentative and gave an honest response to the parent poster. I hate meta-comments, but they wouldn't be necessary if people wouldn't moderate based on personal agreement/disagreement.
Note that this is not about building new plants -- this is only about what happens in the next 3 months to cover the loss in capacity caused by bringing 7 plants down.
You can't just 'dismantle' a plant that still has residual heat being generated.
Additionally, if you're suggesting burying it in reference to the solution at Chernoby, that also doesn't work so well. At Chernobyl the plant was effectively destroyed, so there was no harm in simply filling it with concrete and placing the sarcophagus over it. At Fukushima the plant is still largely intact. Unless you can submerge the plant in concrete in one fell swoop (not possible), the damage done by the piecemeal burying of the plant would undoubtedly create even more damage and result in more radiation leakage than we currently see.
Of course, the infrastructure in the entire region had been destroyed by the earthquake + tsunami, making the simple task of transporting hundreds of tons of sand and concrete a herculean task...
You cant dismantle a plant that still generates residual heat while a used fuel pool is on fire nearby. Its just too dangerous a place for humans to be. What should they have done? Sent Asimo?
Just note that robots don't work either, because particle radiation has a nasty way of flipping bits stored in memory. In the presence of a strong beta ray source, you can treat sram and dram as good sources of truly random data. :)
There are of course ways to shield from that (as illustrated by spacecraft and common military electronics), but nuclear station damage control robotics is perhaps too niche application to be implemented.
FNAL, BNL, CERN ...and KEK all use radhard electronics (obviously not everywhere), admittedly on the fringes of your illustrating application areas. Combined, that is already quite a large area, so to my mind parts for tough (damage) control robotics isn't such a niche.
But true, small production runs and spares is a real issue (actually, by the time they are really used, they are already obsolete -- but this is why you have upgrade plans :).
As I understand it, canadian CANDU reactors use a robotic system to perform online refueling. They also use heavy water as a moderator, and burn unrefined uranium / [can] spent fuel from other reactors pretty impressive machines I think.
