Mawkish1983 wrote:Emergency neutron absorbers (boron is common) should have been automatically deployed, shich would have stopped the reactor heating up by stopping the chain reaction. It seems this hasn't happened, because the core is heating up; the chain reaction may be happening still. It shouldn't be, but it looks like it is.
Boron was injected. In fact, they injected boron almost right away, writing off the reactors as a total loss. There is no sustained reaction going on in the cores. What they are dealing with is the decay heat. Within a day or so of shutting down the reactor, the decay heat is reduced to about 1% of what it was when operating. Of course, that 1% is still millions of watts of thermal energy and needs to be dealt with.
Also, I heard the fire in reactor 4 was from leaked oil, not burning fuel rods as some in the media have claimed.
It is unfortunate that a small amount of fission products were released. However, there still has not been a large release and nothing really nasty so far. Every day that goes by without a complete meltdown is a good thing. More decay heat is dissipated with every passing hour. Either in a few days or a few weeks the reactors will cool enough to be below the boiling point of water. Then they won't have any more pressure or steam building up and things will be pretty much under control.
Had this been a hydro-electric dam or a natural gas plant that failed in the earthquake or subsequent tsunami, a lot more people would have been injured or killed. Generating gigawatts of power has inherent dangers. Nuclear power takes something like 100k times less the amount of fuel of other power sources. That means less deaths and injuries all the way from the mines to the power plants. Orders of magnitude more people have died mining coal than uranium. Wind turbines kill scores of birds every year, and there have been accidents resulting in deaths (people falling off) from wind turbines. Numerous people have died just from touching high voltage power lines. Any way you look at it, there are risks associated with building and maintaining a large high capacity grid. People are unfortunately going to be killed, no matter what technology we employ. The best we can do is attempt to build more safeguards into our systems and learn from past mistakes.
I'm keeping my fingers crossed that this tragedy will spur the development of the thorium fuel cycle. I'd love to see us drop our existing nuclear technology for thorium. Unfortunately, I think with the fear and panic in the general population, and politicians responding to that will squash a lot of future nuclear power development. This is most disappointing to me. I want to see our civilization reach out into space and we're going to need this type of technology to survive if we ever hope to colonize that last greatest frontier. Somehow I doubt that wind turbines and solar panels will be enough to power a space-faring civilization.