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We are now assured that this sort of thing cannot happen here, but we are dealing with a similar political system and similar political systems often produce similar situations, especially when you get a non-expert running a highly technical industry simply because he is politically reliable (just to make sure that everybody understands, I am not simply blaming the Communist system. Three Mile Island showed a similar syndrome under a Capitalist system and produced a similar result for very different economic reasons).
What this all boils down to is that Murphy's Law will operate, that in any calculations we make about risks whether this be the risk of driving a motor car, or taking an aeroplane, or of going to hospital and letting a surgeon operate, or running a nuclear power station, human stupidity must be taken into the calculation as a major factor. What we really want is something that is fail safe, so that even human stupidity cannot cause an accident. Now it so happens that way back in 1956 Dr. Edward Teller, the inventor of the hydrogen bomb, sat down to design a nuclear reactor safe enough for a party of school children to play with and he and his colleagues did design a safe reactor called the "Triga". General Atomic, a subsidiary of General Dynamics, actually built such a reactor and at the dedication ceremony the very famous physicist, Niels Bohr, put the "Triga" through a party trick. He pressed the switch that pulled all the control rods out of the core at high speed which should have caused a catastrophic accident. For a few thousands of a second the output of the reactor soared and then it brought itself under control. The "Triga" proved itself to be inherently safe.
The
All existing commercial reactors rely on engineered safety: use of active devices that detect and then respond to danger. For example, if a reactor core overheats, cooling water is supposed to flood in to prevent a melt down. At Three Mile Island and Chernobyl these systems fell foul of Murphy's Law: If something can go wrong, it will.
it will. The idea must be to replace Murphy's Law with the laws of physics. The law of physics exploited by the "Triga" is that warm neutrons are less effective than cold ones in causing atoms to split. The neutrons in a water cooled reactor are slowed down by collision with hydrogen atoms in the water. Had Mr. Bohr plucked the control rods from an ordinary reactor the fuel would have warmed up but the cooling water would have stayed cold. That means the neutrons would stay cold and fission would continue. But in the "Triga" only half the hydrogen atoms are in the cooling water and the other half are in the control rods so when the fuel rods heat up so do half the hydrogen atoms. The warm neutrons cause less fission and escape faster into the cooling water. By warming up a "Triga" starts the very process that cools the reactor down.
Unfortunately, the biggest "Triga" ever built was a tiny 10 megawatts suitable for research rather than for commercial power generation, and for economic reasons inherent safety never caught on for the bigger reactors: It was too expensive. But now that engineered safety is becoming extremely expensive it is time to go back to designing a commercial reactor with inherent safety built in because the economic penalties for this inherent safety have now disappeared. I understand that there are at least two large American companies working on the "Triga" successor, and the Swedes and Germans are also working on similar projects. Time scale? Well, I guess something like this will take 7 to 8 years to come to fruition and then it
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