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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Type One Energy, TVA ink LOI in development of fusion power in Tennessee
The Tennessee Valley Authority has issued a letter of intent to fusion energy start-up Type One Energy regarding the utility’s interest in the potential deployment of Type One Energy’s fusion power plant technology at TVA’s former Bull Run fossil plant site once it is commercially ready.
Reuben Rainisch, Victor R. Fricke
Nuclear Technology | Volume 87 | Number 2 | October 1989 | Pages 478-485
Technical Paper | TMI-2: Health Physics and Environmental Release / Nuclear Safety | doi.org/10.13182/NT89-A27740
Articles are hosted by Taylor and Francis Online.
During the accident at Three Mile Island Unit 2, a significant mass of core debris relocated to the bottom head of the reactor vessel. Subsequently, defueling activities in the core area redistributed the fuel and caused further core debris to relocate to the lower head region. An analytical approach is presented for determining the relative increase in lower plenum debris bed mass from observed changes in ex-core neutron detector readings. The neutron source magnitude of the fuel in the lower reactor vessel plenum and the degree of subcritical multiplication of neutrons in the lower head are investigated. Based on the mathematical relation formulated, it is estimated that during lower core area defueling (September 1986 to November 1987), between 12 and 23.5 additional tonnes of core materials relocated to the lower head.