Developing maintainability for tokamak fusion power systems. Phase I report. Volume I. Study results

The overall purpose of the study is to identify design features of tokamak fusion power reactors which contribute to the achievement of high levels of maintainability. In this first phase, the principal emphasis is on scheduled maintenance whose frequency is determined by the life of the reactor first wall/blanket. Remote operations are baselined. Five conceptual reactor designs have been analyzed. Each concept is characterized by the size of the replaceable first wall/blanket module--large, intermediate, small--and whether access to the module was from the outside of the reactor, the inside of the reactor or a combination of both. The study results are expressed in terms of availability (scheduled maintenance downtime), the costs of maintenance (capital and recurring) and the percent effect of maintenance on the cost of electricity. During this first phase, the study benefitted significantly by the critical review of the feasibility of maintenance functions and the time-to-perform estimates by numerous persons involved in nuclear maintenance and remote operations