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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fermi America looks to go public as NRC accepts COLA for AP1000s
Texas Tech University and Fermi America are now one step closer to realizing their massive vision for the Advanced Energy and Intelligence Campus in Amarillo, Texas, as the Nuclear Regulatory Commission has accepted the first two parts of its combined license application (COLA) for four Westinghouse AP1000s.
Paolo F. Venneri, Michael Eades, Yonghee Kim
Nuclear Technology | Volume 197 | Number 1 | January 2017 | Pages 64-74
Technical Paper | doi.org/10.13182/NT16-80
Articles are hosted by Taylor and Francis Online.
This paper explores the possibility of passively controlling the reactivity of a nuclear thermal propulsion (NTP) reactor. The objective of this study is to limit the use of the radial control drums to start-up and shutdown procedures and ensure that the exact same operation is performed for each full-power burn. To achieve the goal, this work considers several design measures, which include a low-density burnable absorber in the tie-tube components of the core, the use of variable hydrogen density in the moderator element coolant passages, and the judicious selection of a modified mission profile to maximize the decay of 135Xe after operation. In addition, the improved stability from the enhanced fuel temperature feedback due to the implementation of low-enriched-uranium fuel is also exploited for the realization of passive reactivity control. In this work, a passive reactivity control system is implemented in the Superb Use of Low Enriched Uranium (SULEU) NTP core and analyzed in terms of its ability to fulfill a NASA Mars Mission Design Reference Architecture 5.0–style mission. It is concluded that the use of the control drums can be limited to start-up and shutdown operations only, eliminating operator input in order to maintain a constant power level in the core.