Virtually all of the nuclear reactors in the U.S. are of the same archaic design as those at Fukushima (Indeed, MSNBC notes that there are 23 U.S. reactors which are more or less identical to those at Fukushima.)
Called “light-water reactors”, this design was not chosen for safety reasons. Rather, it was chosen because it worked in Navy submarines.
Specifically, as the Atlantic reported in March:
In the early years of atomic power, as recounted by Alvin Weinberg, head of Oak Ridge National Laboratory in his book The First Nuclear Era, there was intense competition to come up with the cheapest, safest, best nuclear reactor design.
Every variable in building an immensely complex industrial plant was up for grabs: the nature of the radioactive fuel and other substances that form the reactor’s core, the safety systems, the containment buildings, the construction substances, and everything else that might go into building an immensely complex industrial plant. The light water reactor became the technological victor, but no one is quite sure whether that was a good idea.
Few of these alternatives were seriously investigated after light water reactors were selected for Navy submarines by Admiral Hyman Rickover. Once light water reactors gained government backing and the many advantages that conferred, other designs could not break into the market, even though commercial nuclear power wouldn’t explode for years after Rickover’s decision. “There were lots and lots of ideas floating around, and they essentially lost when light water came to dominate,” University of Strasbourg professor Robin Cowan told the Boston Globe in an excellent article on “technological lock-in” in the nuclear industry.
As it turned out, there were real political and corporate imperatives to commercialize nuclear power with whatever designs were already to hand. It was geopolitically useful for the United States to show they could offer civilian nuclear facilities to its allies and the companies who built the plants (mainly GE and Westinghouse) did not want to lose the competitive advantage they’d gained as the contractors on the Manhattan Project.
Those companies stood to make much more money on nuclear plants than traditional fossil fuel-based plants, and they had less competitors. The invention and use of the atomic bomb weighed heavily on the minds of nuclear scientists. Widespread nuclear power was about the only thing that could redeem their role in the creation of the first weapon with which it was possible to destroy life on earth. In other words, the most powerful interest groups surrounding the nuclear question all wanted to settle on a power plant design and start building.
President Lyndon Johnson and his administration sent the message that we were going to use nuclear power, and it would be largely through the reactor designs that already existed, regardless of whether they had the best safety characteristics that could be imagined. [Nixon also fired the main government scientist developing safer types of reactors, because he was focused on safety instead of sticking with Nixon’s favored reactors.] We learned in later years that boiling water reactors like Fukushima are subject to certain types of failure under very unusual circumstances, but we probably would have discovered such problems if we’d explored the technical designs for longer before trying to start building large numbers of nuclear plants.
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