Tuesday, 15 March 2011
Fukushima and the future of nuclear power
Back in university I wrote an essay on safety and nuclear power. Basically my analysis was that a water-cooled reactor could never melt-down under conceivable circumstances, that 3-Mile Island only suffered partial meltdown because of a series of avoidable accidents, and that an accident that knocked out both the primary and back-up cooling systems would probably also destroy the reactor and was therefore not worth worrying about.
I also wrote that Chernobyl exploded because it was basically a bomb - the graphite blazed out of control after the initial melt-down, no-one would build another reactor like that in the future. The conclusion was that another major nuclear accident like Chernobyl was almost impossible.
Yes, I know Fukushima hasn't gone into full meltdown yet, and the reactor vessels are, as far as we know, still in tact. However, the circumstances I described as being inconceivable have occurred - an accident bad enough to knock out the cooling systems, but not so bad as to destroy the reactor. Moreover, if explosions can tear reactor containment buildings apart in the way they did at Fukushima, the reactor itself can also be destroyed, and the fuel spread over a large area in just the same way the Chernobyl explosion did. It didn't happen, or at least it hasn't yet, but it could have.
I'm a long-term supporter of nuclear fission power, but I also think that this accident should at the very least give the supporters of nuclear fission food for thought. There are reactor types at the experimental stage, such as inert gas-cooled reactors which should not be vulnerable to the chenical explosions that tore apart Chernobyl and the Fukushima reactor buildings. This won't eliminate the low risks associated with spent nuclear fuel though.
On the other hand, the German government's de-activation of seven of the seventeen nuclear reactors in Germany is a ridiculous over-reaction.
[Picture: A satellite picture of the explosion at the Unit 3 containment building at the Fukushima I plant. Picture made available by DigitalGlobe under a CC-by-ND-NC 2.0 license.]
Posted by Gilman Grundy at 16:29