LyrArc Article Gist
The Nuclear Safety Commission of Japan, one of two safety regulators in Japan, met in October 2010. At that meeting a presentation by Takanori Tanaka, head of the government supported Nuclear Power Engineering Center, advocated new technologies that would reduce risk in the event of earthquakes and tsunamis. The presentation focussed on new plants and did not go into retrofitting old plants with new backup solutions for cooling in the event of electrical failure. A recent article by Hitachi researchers brought up the idea of isolation condensers which could provide temporary power supplies in the event of electrical failure. One such device was on No. 1 reactor at Fukushima (built in 1971), and worked after the quake but later failed. The views of nuclear engineers at Hitachi discussed here show that cost remains a constraint in the design of nuclear reactor cooling systems, and redundancy with several layers of diverse backup systems for cooling are not being pushed by companies building the reactors. See the group articles for G.E.'s Mark 1 system which show cost and easier to build were factors behind the smaller containment systems favored for that design. Fukushima plant uses the Mark 1 reactors. Without independent safety regulation that does not rely on the companies for analysis and solutions, regulation risks becoming too dependent on companies for coming up with the strong safety precautions that are absolutely essential. These safety precautions can succumb to cost pressures....