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reactor designs as part of the attempted revival of the fi

        It is more or less inevitable, I suspect, that even those who have discerned the wrongfulness of fission power become, in the course of looking into it, fascinated by clever ideas that have emerged in that warped line of invention.  I have found no difficulty in conceding that some very clever ideas have been generated by those understandably but mistakenly working on fission power reactors.  Their lacks are not in cleverness but elsewhere.
        One of my favourites has been the molten-salt reactor.  The vessel is rather like an upside-down pear.  The coolant, which is also the fuel, is a molten salt of a fissile nuclide.  As it flows upward thru the vessel, it forms briefly a critical mass when it arrives at a critical cross-sectional area.  The heat produced in that zone is carried by the flowing fuel/coolant upwards and out of the vessel to a steam generator, and the still-molten salt is pumped around to the bottom of the inverted pear again  ...

        Here's a recent array of fission power reactor concepts.  You can safely assume that each entails hidden problems, and I doubt the IEEE will do much to discover them.  More worrying is the fear that the Union of Concerned Scientists will not have the expertise to appraise these 7 concepts:
http://spectrum.ieee.org/energy/nuclear/nuclear-reactor-renaissance

        It is sometimes difficult to foresee defects of a particular reactor design.  I stumbled upon an example when browsing in the library of the NZ Institute for Nuclear Science (in the lateish 1970s).  One of their nuclear enthusiasts had written a report on an official overseas tour, and this was on the open shelves.  It reported that the British prototype for a 'steam-generating heavy water moderated reactor' (SGHWR  -  at Winfrith Heath) had shown a positive void coefficient of fission power: if a void develops in the core, the fission power increases (as contrasted with one of the inherent virtues of LWRs, in which the coolant is also the moderator).  This is a menacing characteristic, because such a reactor could well melt itself by a positive-feedback runaway even if there has been no large loss of coolant.   This reactor type had looked relatively attractive to the pro-nuclear clique in NZ, but this report by one of their own appeared to put them off it.

        The present sales efforts of the nuclear trade is largely reliant on the PR image 'new, much safer reactor concepts'.  On past performance, these will not be properly appraised by suitably sceptical experts.  Never forget that the containment of the GE BWR was 'designed' in their sales dept  ...

RM