An assessment framework for engineering feasibility and constraint diagnosis in fusion energy pathways

This study provides a comparative analysis of six fusion pathways using a four-dimensional conceptual framework: Technology Maturity (TM), Bottleneck Mitigation (BK), Diffusion (DF), and Future Potential (FP). Our analysis focuses on diagnosing current fusion pathways rather than forecasting commercialization or assigning a single composite ranking. The findings highlight that the success of fusion pathways depends not only on technological readiness but also on engineering deliverability. By grouping bottlenecks into four clusters (supply-chain & deliverability, fuel-cycle & resource preconditioning, tech-engineering coupling, governance & expectation-setting), we propose a dynamic, sequenced approach to intervention. The study reveals that while all pathways show high FP, near-term progress is constrained by bottlenecks, particularly in fuel-cycle closure, material durability, and maintainability. We also observe a misalignment between DF and FP, suggesting that managing these competing goals requires strategic governance and policy interventions. Additionally, AI and high-performance computing (HPC) platforms play a crucial role in accelerating technology development and mitigating bottlenecks.