Results of an international study on a high-volume plasma-based neutron source for fusion blanket development

A number of scenarios for fusion facilities were evaluated using a cost/benefit/risk analysis approach. Blanket tests in the International Thermonuclear Experimental reactor (ITER) alone with a fluence of 1 MW·yr/m² can address most of the needs for concept verification, but it cannot adequateIy address the blanket component reliability growth/demonstration testing requirements. An effective path to fusion DEMO is suggested. It involves two parallel facilities: (a) ITER to provide data on plasma performance, plasma support technology, and system integration and (b) a high-volume plasma-based neutron source (HVPNS) dedicated to testing, developing, and qualifying fusion nuclear components and material combinations for DEMO. For HVPNS to be attractive and cost effective, its capital cost must be significantly lower than ITER, and it should have low fusion power (nearly 150 MW). Exploratory studies indicate the presence of a design window with a highly driven plasma. A testing and development strategy that includes HVPNS would decisively reduce the high risk of initial DEMO operation with a poor blanket system availability and would make it possible - if operated parallel to the ITER basic performance phase - to meet the goal of DEMO operation by the year 2025. Such a scenario with HVPNS parallel to ITER provides substantial savings in the overall R&D cost to ward DEMO compared with an ITER-alone strategy. The near-term cost burden is negligible in the context of an international fusion program with HVPNS and ITER sited in two different countries.