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	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>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