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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
G. Prillinger, A. Fischer, Eva Fischer, H. Krause
Fusion Science and Technology | Volume 2 | Number 2 | April 1982 | Pages 301-312
Technical Paper | Shielding | doi.org/10.13182/FST82-A20762
Articles are hosted by Taylor and Francis Online.
Results of discrete ordinates radiation transport calculations are presented for the proposed tokamak ignition and bum control experiment ZEPHYR. As a first step, baryte concrete with 0.15 wt% B4C was identified as an optimum concrete for the shielding fitting tightly around the torus and some attached devices. This shielding material with a maximum thickness of 70 em allows personnel to enter the experiment hall just a few hours after termination of a worst-case bum discharge sequence. Inside the vacuum vessel, delayed dose rates amount to several tens of rem/h after only 50 s of plasma bum for waiting times that are typical for maintenance and repair, thus, remote handling equipment is required. Bootstrapped radiation transport calculations for neutral beam injectors show them to be strongly activated after the worst-case discharge sequence with typical dose rates of some rem/h. Thus shielding is required around the injector boxes and most repair tasks have to be performed remotely. Delayed dose rates outside the torus shielding in front of typical straight diagnostic ducts with diameters of 15 to 25 em are shown to be significant but “hands-on” maintenance of the diagnostic equipment will be possible with some restrictions on working time.