Should fusion future be global or domestic? A multi-regional input-output analysis

• This paper compares global vs. domestic fusion supply chain strategies. • Uses MRIO analysis for economic and environmental impact assessment. • A monopolistic supply chain benefits the host country but reduces global growth. • A balanced supply chain policy for global fusion industry growth is essential. As the commercialization of fusion energy development accelerates globally, a policy debate has emerged regarding whether the future supply chain should adopt an internationally collaborative approach, similar to ITER, or prioritize domestic capacity development. This study evaluates the economic and environmental impacts of constructing and operating a 1 GWe (2.98 GW fusion power) tokamak fusion power plant using a multi-regional input-output analysis. It compares the implications of promoting international cooperation versus a self-sufficient national model, comparing China, Japan, the UK, and the US as case examples. The results indicate that prioritizing domestic procurement benefits the host country's economy: 85–95% of the economic effects were observed in the host country when construction and operation were conducted within a single country. In contrast, international cooperation reduced this effect to 45–71% for the host country. However, domestically exclusive procurement diminished global economic development, underscoring the importance of a supranational perspective in fostering the global fusion industry. In all scenarios, the value-added (direct and indirect profits and incomes for supply chain companies and workers) resulting from fusion power generation were up to 90% of the cost of fusion electricity, indicating that fusion energy is economically advantageous for its stakeholders. Adopting a comprehensive, global view of the supply chain is essential to advance fusion as an industry.