Consideration for the safety of a fusion power plant

Konishi, Satoshi

Based on the fundamental approach for safety of ITER, possible extension to assure safety of fusion power plant was considered. Although the entire analysis and licensing preparation are specific for ITER, its methodology that take full advantage of inherent feature of fusion is expected to be applied to fundamental logic of fusion power plant. Both energy and radioactive source terms that could be potential hazards are typically of order of days of operation rather than a year in the case of fission. Major difference from the test reactor ITER identified was power blanket, coolant loop and generator train that will hold high temperature and considerable amount of tritium. It is anticipated that tritium inventory and most of the tritium safety plant would essentially be same as ITER, tritium recovery and removal from blanket loop will dominate the fusion power plant tritium systems. Such a tritium system will actively remove tritium at the daily throughput comparable with the order of plant inventory. This feature suggest no dedicated off-normal systems are needed to assure safety of fusion plant from the aspect of environmental tritium release.