Germany shuts down seven reactors‎ because of Fokushima

Edit: If you want to read up on the radiation levels: http://www.stratfor.com/analysis/20110315-red-alert-radiatio...

The un-posed question is "what happens if a group of terrorists fly an A380 directly into one of these plants"? Someone on reddit was mentioning that a nuclear plant in Texas was built to "withstand a direct hit from an F-16 traveling at supersonic speeds", but I guess an A380 is so much heavier and larger than a F-16. Because right now terrorists don't even need to get access to the US aerial space, they can hit a nuclear plant in Mexic (let's say this one http://en.wikipedia.org/wiki/Laguna_Verde_Nuclear_Power_Stat...) and still be able to cause important damage to the US population.

Here's the reddit comment I was talking about: http://www.reddit.com/r/pics/comments/g3tfr/and_you_are_tell...

I honestly wouldn't have bet on the Nuclear Plant only a week ago.

I'll add that besides the headlines, Thailand is considering to cancel its 5 plants project. Fortunately, this simply means lobbying will be a bit more expensive.

Waiting this one out doesn't tell us more about the frequency of occurrence (it already occurred), but it does tell us about the magnitude of damage, which is one of the biggest unknowns and arguably why the US caps nuclear plant liability at ~12 billion via http://en.wikipedia.org/wiki/Price%E2%80%93Anderson_Nuclear_... .

The overt reason was that it was such an unknown that no one could insure it; a cynic might say that the cap was known to be incredibly low from the outset, and it was really just a hidden subsidy towards the creation of fuel for more and more nuclear weapons (this was the late 50s).

But people dying from illness from lack of clean water because their water treatment plant is offline and their hospital is out of emergency power doesn't get TV ratings, pageviews, and political attention like apocalyptic visions of radioactive fallout.

I know this is almost a tautology, but when the stakes are as high as a nuclear powerplant, it's important to consider. Nuclear powerplants are the poster-child of massively redundant fail-safes. If we (as a species) are not able to design a system to withstand natural disasters when we know the stakes are as high as possible, then maybe we shouldn't play that game. While a massive tsunami is rare, it's not necessarily rare on the time scale that we expect nuclear plants to be operational. Given our track record, perhaps we can expect a serious problem once every 50 years. That's really infrequent - but it still might be too frequent considering the consequences.

I haven't come to any conclusions, and I don't think bhousel has, either. But the past few days have given us more data to churn on.

But I didn't realize that keeping a reactor vessel (and fuel storage pools) cool after the reactor has been scrammed is such a challenge. I also didn't know that hydrogen explosions are a normal byproduct of cooling down a reactor core. Yes, I know that there are third generation reactor technologies available today that don't have all of these issues, and fourth generation technologies in development. I really do believe that we should be investing in these technologies to make nuclear power safer.

Unfortunately now we're stuck with a lot of aging reactors that are operating past their design life, and a public that is unwilling to bear the cost of the upgrades.

Japan is probably about the best prepared place that this incident could happen, and even they are having trouble keeping their scrammed reactors cool. And another earthquake could happen tomorrow, making the situation even more unmanageable.

I have far less confidence in almost any other country being able to handle a crisis like this. Nuclear power is clearly here to stay - Germany may eventually turn it's back on the technology, but there are dozens of third world countries running reactors now (or trying to).

Our focus really should be on making nuclear power as safe as possible, not on preventing it entirely. Perhaps the biggest problem with this current crisis is that it is the first nuclear incident where we can't just explain it away as 'human error'. Everything did work exactly as it was designed to, with the best trained people handling the crisis, and we still can't have complete confidence in the technology to cool itself off without releasing radiation into the environment.

http://en.wikipedia.org/wiki/List_of_earthquakes_in_Japan

8,3, 8.5 and 8.4 are three major earthquakes I see before mid-20th century. If you're building a power plant, it should survive a large safety factor above the largest earthquake you have ever seen, especially since the cost of failure is pretty darn high. I don't think it's unreasonable to expect to survive an 8.9 in a major earthquake zone, especially since the largest earthquake the world saw after the 1900s was around 9.5.

I think the fact that the diesels in Daiichi failed because of seawater flooding is yet another gigantic contingency failure. The Japanese know that earthquakes are followed by Tsunamis. What happened?

I used to be pro-nuclear but I'm reconsidering my decisions too. I don't think that humans can be trusted with doing things right, such as decommissioning old plants in time or building in extra safety factors even though it costs way more money to do so. Furthermore, I shudder to think what a deliberate attack attempt at a nuclear plant (or several ones simultaneously) could do. If there are people who drive planes into buildings with no regard to their own life, there will be those who attack nuclear plants also.

Edit: reasons for downvotes would be appreciated to further the discussion.

I did find myself wondering if the impressively engineered AGR site at Torness would survive a 20m tsunami - almost certainly not as I suspect this wasn't part of the requirements.

Disclaimer: I still think fission power might be better in the long run than coal power (catastrophic global warming is worse than any nuclear disaster), but I'd rather do without either and strive for 100% renewable energies. It can be done, just needs the willingness to do it.

the result might be not positive enough regarding the possible long-term damage it still can have to the environment and the japanese people (35M in tokyo area alone).

The technology works incredibly well. And in Japan, the people are well trained and prepared, and I have every confidence that they'll be able to cool the reactors down without releasing much radiation into the environment, as long as nothing else goes wrong.

Now take that exact same reactor and build it in Iran, Bangladesh, Congo, Libya. Do you have the same confidence in it? Japan was a best-case scenario.

Yet I bet you go on eating food, in the belief it will keep you alive.

The problem at Chernobyl is not as you describe. The issue there was that through a process of bad core management, while trying to shut down the reactor and at the same time run an experiment, meant the core ended up in a very unstable state. Mostly the instability was managed automatically but at some point it went wrong; there is much debate over this, though conventionally it is accepted that someone, it is not known who, SCRAMmed the reactor - the poor design of the control rods meant that rather than immediately stop the reaction it actually made things worse as they were inserted, causing the core to overheat causing extreme pressure, cracking the control rods and essentially making the situation unrecoverable. Then a steam explosion broke the pressure seal and the chamber emptied of coolant.

After that the exact mechanics of what happened is somewhat unknown (instrument failure) but the lack of coolant lead to a critical "nuclear excursion"; i.e. essentially the neutron emission becomes so large that the fuel becomes supercritical. The excursion heated the fuel so that it expanded and "exploded" out of the pressure vessel; once that had happened the fuel was dispersed and the nuclear reaction ended.

At that point the graphite was exposed to the air and caught fire; it was this (and the resulting smoke plume) that spread most of the radiation.

You misunderstood. No one reasoned that loss of water coolant would somehow cool the reactor (that's self-evidently absurd); they reasoned, and still reason, that loss of coolant would shut off the fission reaction. This rules out, not meltdowns, but uncontrolled power excursions like the one that created the steam explosion that blew up Chernobyl.

The light water is the coolant AND the moderator. You need a moderator that slows down the emitted neutrons to keep the nuclear chain reaction going.

But evidently, the water is not the only moderator they use. They don't use graphite, though.

In 2010, 16 percent of all electric power in Germany came from renewable sources (6.4 percent wind, 4.2 percent bio mass, 3.2 percent water, 1 percent photovoltaics, 0.8 percent waste). Coal is at 43 percent, nuclear energy is at 23 percent, oil and natural gas are at 15 percent. (Source: http://www.bmwi.de/BMWi/Navigation/Energie/Statistik-und-Pro...)

The current government thinks that ramping up renewable energy to replace nuclear energy until 2030 is realistic.