Thorium has to be mined and the U233 created is the most perfect bomb fuel. It has the very low critical mass if Pu239 but the low spontaneous fission rate of U235 lower actually. So you can make a gun type device with less than 10kg of materials and fit it in a real backpack. Thorium will never happen in the USA the proliferation risk is simply too great.
Second point fast fission reactors can use 100% of natural uranium U238 & U235 as fissile and fertile. The USA has 600,000+ tons of depleted uranium from our enrichment plants in storage that is enough fuel for a thousand years or more of 100% the total energy consumption of the USA in fast reactors spectrum with integrated reprocessing. The first reactor to produce power was not a pwr it was the IFR number one in Idaho at the National lab there. It proved that with integrated out I processing you one can burn all of natural uranium down to fission ash, two that the breed ratio is positive allowing you to spawn daughter reactors, and three the only waste coming out is fission products with half lives of under 300 years. All the actinides are fissile in a fast spectrum reactor and are recycled into the fresh fuel. Id,Tc and Cs have long lived fission products those are also recycled into fresh fuel and in the fast spectrum undergo transmutation in to short lived fission products. The waste form from pyro processing is solid ceramic glass with zero potential for geological mobility under hydrates conditions. The other form is a none water soluble rock.salt again with zero geological mobility in bore hole disposal or rock vaults.
This natirum reactor is a fast spectrum reactor with integrated processing to follow. The innovation is removing the sodium to steam generator. By using a molten salt intermediate as a heat transfer fluid they eliminate the possibility of a molten sodium water reaction. The chosen Molten salt is inert in molten sodium. Using a molten salt also allows them to very cheaply store heat on a gigawatt scale. This means they can run the reactor flat out at 100% power 24/7 which is how a reactor is designed and it’s peak efficacy point. When grid demand is low you bank the molten salt in cheap tanks, when peak demand is on you pull the salt out of the tanks and run your peaker turbines it’s genius. You could also use the 600C+ degree salt for process heat such as the iodine sulfur cycle to generate hydrogen from water on a scale measured in the millions of kg per year
. Hydrogen is needed in massive amounts for oil refiners to meet sulfur regs and to crack heavy oils and visbreaker residues into petrol, gas oil, and lpg. The heat on the bottoming cycle at 100C can drive seawater desal for a fraction of the cost of RO membranes. Isreal has got RO down to 58 cents or less a cubic meter. Nuke bulk heat would be even cheaper. For point of comparison water in DFW is $4.50 per 1000 yank units er gallons. There is 264 USG in a M^3 so $1.18 per cubic metre which means Israel desal water is already half the cost of water in North Texas. DFW also charges $5 per 1000 for wastewater treatment up to your first 8,000 gal or the avg use for the months of Dec, Jan, Feb the prior year whichever is less. Point is once you have massive amounts of heat stored and available you can do lots of industrial things with it cheaply.
Nice write-up. Thanks.