Possible use of Thorium in Gen II-III and Gen IV Reactors [5. GIF-INPRO/IAEA Interface Meeting]

Summary: • Potential of thorium as additional resource to uranium → Controversial vision of merits in abundance, radiotoxic inventory and TRU production. • Industrial infrastructure, research, design and licensing data do not exist to rapidly use Th-fuels in existing reactors. Significant effort of R&D needed for reprocessing Th fuels; • Excess Pu burning on Th matrix as possible first application of Th; • Candidate fuel cycles with thorium: – Once-through in LWRs or HWRs (saving of Unat < 20%); – Closed UTh cycle in LWRs, HWRs or HTRs (saving of Unat ~30-40%); – Symbiotic fleet with Thermal & Fast Neutron Reactors (potentially sustainable). • Significant R&D needs to prove feasibility + Licensing basis → Th-fuel, Reprocessing, Fabrication, Optimization of Th-fuelled core designs. • Commercial viability still to be demonstrated → Uranium price, cost of recycle ²³³U and Pu, cost of fuel cycle back-end… • Proliferation issues of UTh fuel cycles with <20% fissile content are comparable with those of the UPu fuel cycle → IAEA, INFCE Summary Volume 1980