Review of the total system related to operation of nuclear-powered ship

It is essential to establish a marine reactor having excellent safety and reliability, which is capable of competing economically with conventional ships, and which can be accepted by international society, in order to be prepared for practical application of future nuclear-powered ships. For this purpose, it is important not only to demonstrate a marine reactor using a model or test device to simulate actual operation, but also to establish the environmental requirements for operation of a nuclear-powered ship, such as safety standards that are operationally and internationally common for ships, and to establish a repair base for nuclear-powered ships. Systems research for the practical application of nuclear-powered ships was conducted for five years, fiscal years 1992 through 1996, by a group in the Japan Atomic Energy Research Institute (JAERI), under the project title 'Review of the total system related to operation of nuclear-powered ships.' The project sought to summarize requirements for the practical application of nuclear-powered ships from the standpoint of the need side, e.g., what nuclear-powered ships will be requested, and what functions will be provided under the expected future social environment; to show a complete system concept for the operation of nuclear-powered ships; and to clarify the situations creating demand for nuclear-powered ships, as well as the system and environmental conditions to be established for operation of practical nuclear-powered ships. Study considerations included the size of the operation system for a nuclear-powered ship, a scenario for introducing a nuclear-powered container ship, and economic evolution from the effects on the whole shipping system, based on container ships, of introducing a nuclear-powered ship. The results of these considerations were made the framework for constructing an entire system and evaluating its economy. The treatment and disposal of radioactive waste from a nuclear-powered ship, and the establishment of laws and standards related to the operation of a nuclear-powered ship, were discussed. The group evaluated shipping costs for nuclear-powered container ships using the MRX (Marine Reactor X, as currently designed by JAERI), sailing the North Pacific route. The cost report focused on whether large, high-speed container ships with the MRX, carrying a varying number of containers (4000, 6000, and 8000 TEU) and sailing at varying ship speeds (25, 30, and 34 knots) could compete economically with diesel ships. Comparing transportation costs for diesel container ships and nuclear-powered ships operated on the Pacific Ocean, we found that the latter had an advantage over the former when ship speed was over 30 knots. (author)