Tritium production and processing systems for ST-E1

Abstract An integrated tritium fuel-cycle architecture has been developed for ST-E1, a low-aspect-ratio, high-power fusion power plant. The approach couples a helium-cooled liquid-lithium breeder blanket with a dedicated circulation loop providing tritium extraction, heat removal, and inventory control within a unified system boundary. Downstream of the blanket, the tritium processing system comprises of extraction, purification, isotope separation, and storage subsystems sized to accommodate the plant’s dynamic tritium production and consumption rates. Inventory modelling is used to assess candidate extraction schemes, evaluate tritium residence and holdup, and quantify sensitivities associated with protium control and intermediate inventories. The integrated assessment indicates that the combined blanket-processing architecture can satisfy startup and steady-state tritium requirements within credible operating margins, with a low overall inventory and acceptable doubling time. The results identify tritium extraction sensitivity and fuelling efficiency as the dominant drivers of inventory performance, rather than marginal improvements in breeding ratio. Overall, the analysis demonstrates the feasibility of a self-consistent fuel cycle for ST-E1 and highlights the critical dependencies between blanket inventory management, processing throughput, and overall plant performance.