Re: Small Nuclear Power Reactors

[Jones Beene]

Some time ago Jed Rothwell posted the original message: "All kinds of interesting stuff has been added to this UIC web site lately. It is impressive. Almost too impressive; I fear they might succeed and hold back the development of CF! Main index: http://www.uic.com.au/nip.htm Having seen this earlier posting as a segue - in a continuing multi-year effort to kluge together, with limited resources, a much-improved reactor concept - really a pre-design based on achievable goals - I had updated some past posts with the following. But, alas, just noticed the fact that it was never sent (apparently)... or at least didn't show up in the archives. Maybe a "carnivore" captured it  ;-)  This kind of subject matter is of limited interest to current vortex posters, except for RvS it seems, but the archives will preserve it for a few years, and if it turns out that there is anything valid or pertinent in it, then hopefully it may serve as a seed for future development. It makes more sense than anything currently on the scene (if I do say so myself) and much more detail is available (for the cost of a modest consulting contract). The scheme is to use an intense "independent" neutron source as a "substitute accelerator" for a variant of the Rubbia-type plan. Dr. Carlo Rubbia is a famous guy at CERN, but basically an idiot when it comes to putting together a cost-effective strategy for an advanced reactor that can burn its own waste. However he did popularize the base-concept, and deserves some mention for that - even as deficient as his design is/was. Rubbia designed an integrated accelerator-driven power reactor AND waste clean-up unit, which is a great idea... but...stops far short of optimum, and in this present alternative design, one could save $500 million in capital cost by ditching the accelerator, another $200 million by using an unpressurized reactor scheme, with a natural Uranium "primary" unit, and the waste in a "secondary" adjoining unit - and another approximately $2 billion by making it modular and "mass-produced" (a few hundred to a thousand units per year).   This is no joke - approximately $2 billion of the cost of any planned or recent-past nuclear plant in the USA goes (went) to bankers - as it is the result of interest payments combined with very long construction timing - one-off as the Brits like to say. That is now part of an entrenched political reality. Kind of "Bohemian," one might suggest. But it does not "need" to be that way.   All of this can change with a number of identical, mass-produced, modular rail or ship-mounted units, that are sold as turnkey packages. It takes 10-20 modular units for a normal plant. Obviously one cannot rail-mount either a proton accelerator of a steam plant. Those eggheads at CERN may know their nucleonics down to the last quark, but they have no real-world idea of how and why low capital costs, and modularity are extremely important in the commercial arena. My preferred source for robust neutrons is/was a small aqueous homogeneous reactor (basketball-sized) using heavy water and a small amount of dissolved uranium nitride. Here you have a $50,000 replacement for a $500 million mile-long accelerator. Yes, you will need several for comparative purposes - as we are talking about smaller, modular units rather than a single large complicated plant. "Free" neutrons are - pound for pound, among the most valuable commodities on earth (even if you can only weigh them theoretically). There is no cheaper way to produce them in a fairly intense flux (10^12 per cm^3) than in the homogeneous reactor. It is super-safe even if it does require a few kilograms of highly enriched fuel. There are ways to eliminate the proliferation risk of this. The larger-reactor itself is a breeder, and with ongoing partial-reprocessing, so that the initial loading of both the homogeneous core and the much larger natural U blanket is sufficient for a 50 year life. It is not that there is no refueling - there is in fact continuous refueling and reprocessing. But the difference is that all the fuel which is needed for 50 years is included at the outset. Burnup is 90%. All waste which is not removed in the minimal ongoing reprocessing, is burned in situ. With a cheap source of "makeup" neutrons - to be employed in smallish, mass-produced rail-mounted subcritical reactor of about 50 MW each, fueled by natural uranium - there is a lot of borrowing of other concepts... so there is similarity here to the CANDU or newer ACR700 - which designs are a pressurized plumbing nightmare, and do not get the full benefit of an extremely "cheap" source of neutrons - although the worst kept secret in nuclear engineering is that there is a huge anomaly in how many "free" neutrons one gets from a deuterium moderator.   Here, the central core contains heavy water, a few Kg of dissolved U-nitride and a duct to a very small deuteron accelerator - used for startup only. Both the core and blanket are nominally subcritical.  And after a threshold flux has been initiated, and a magnetic field is imposed, then both go critical, whereas neither will do it alone and without the magnetic field.   There is zero meltdown or runaway risk - as a homogeneous reactor is inherently safe and the heavy water will boil away quickly if the flux becomes too high. The flux is made asymmetrical and shifted outside the central core and into the U-carbide blanket by the clever use of magnetics. The rest of that part is proprietary, as is the direct conversion scheme. Both have been hinted at in the literature, but no-one has apparently put it all together in a hybrid package. A total redesign, with an eye towards smaller, cheaper, safer, and no-steam (direct electrical conversion) could have be done here in the USA anytime in the past two decades, were it not for the special interests of the "club" dominated by the General Electric Company, which is second to only Halliburton-Big-Oil in political clout (and has been for 60 years previously). We have billions of dollars of sunk cost in a military-focused infrastructure... consisting of antiquated dangerous technology, based on using enriched fuel at low burn-up - totally irresponsible - and this is dependent on a highly subsidized military use of enriched-fuel. The club is locked-in by these past errors. All of which was instigated by GE and Westinghouse and their minions at DoE and DoD - and with little willingness to change things at the highest level.   It is a source of amazement that some European country has not stepped-in with a better answer, but the unnecessary baggage and political problems for nuclear energy are even more severe there. France and England have their own special interests, and Germany is the only other country with enough "brain-power" to pull it off - but they have different political hurtles to overcome and a strong and mis-informed green party. China is developing the brain-power and probably can do this in the next generation - 2020 and beyond. For now, it is all sloshing around in the muck of special interest politics. There is a most important and "telling" but also "dated" expose online "The Bohemian Grove and The Nuclear Weapons Industry" originally published in 1987, and much information in the article is not current so far as many of the names have changed.   But the point of the article is even more disturbing now than then, because this high-level "club" influence in greater in Washington now than at any point in the post-war history. Sure, the positions in the larger "club-of clubs" consisting of representative of skull-and-X +bohemian +Texas oilers + whatever.... have changed, some individuals named have died, and the status of many facilities has (nominally) changed, and Halliburton has entered the club in a big way. Otherwise - this is our big national problem with going nuclear - special interests.   Otherwise, many acceptable and ecologically sound answers have been out-there for some time (although none of them make as much sense - in an integrated package - as does this one ;-)   Jones