Global nuclear pool

Abundant and scarce nuclear resources

Thorium in millions of tons – shuffled into MSRs – is a more abundant and sustainable energy source than petroleum, uranium, hydro, wind and biofuels ever were. Plutonium exists in thousands of tons of reactor waste and decommisioned weapons material. There’s a million tons of depleted uranium238 ; a fertile isotope that could be converted to fissile plutonium239 for energy production. Proton accelerators, ADS electroplating, could be investigated for this purpose.

Uranium235 – 0.7% of natural uranium – is the scarce resource for today’s reactor fleet. 80 000 tons of natural uranium are wasted to produce measly 400 GWe yearly, an efficiency of some 0.5 -1 %. Given confirmed resources and planned water reactor fleet expansion from 450 to say 1000, natural uranium might be exhausted in some 20-40 years of business as ususal; a considerably less time span than the expected reactor life time of 60 years. Uranium supply is set up to follow the same steeping decline as oil and gas. Where’s the economic soundness of business as usual – in particular at rapidly expanding water reactor costs ?

Management of global pool

Thorium plays no role today. The future thorium reactor fleet must burn thorium to energy as well as breed uranium233. In the long run ~100 years breeding must be sufficient, ie at a sufficently low doubling time, to supply start charges organically to an independant thorium fuel cycle globally. However in the short run, start charges for the ThMSRs are available from decommisioned weapons plutonium, enriched uranium235 and reactor waste.

Rod breeders

To increase the efficiency from shameful 0.5 -1%, breeding in today’s uranium/plutonium fuel cycle is forecast in advanced reactors cooled by sodium or lead, LMFBRs.  Not only do these advanced fast breeders and the associated reprocessing come at an enormus cost; they are considered risky and proliferant. This means that, even in the highly improbable scenario that all new reactors are fast uranium/plutonium cycle breeders, they will not sustain their own fuel cycle, let alone guaranteeing global fuel supply under a regime of rapidly expanding nuclear energy production when natural uranium output is fast declining. Rod breeders are not sustainable. Wasting fissile resources in either uranium or thorium rods should be phased out asap.

To secure a global and perennial thorium fuel cycle, liquid chloride reactors should be used to breed the uranium233 pile. A perennial electronuclear scenario is no less all-important than managing the unvaluable ocean fish stock and the human genome.