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Kentucky legislature sends nuclear bills to governor
Kentucky’s Republican-majority legislature passed a bill this past week that could bring nuclear energy to the “coal-is-king” state as lawmakers broadly seek solutions to reduce carbon emissions. The bill went to Democratic Gov. Andrew Beshear on Monday for final approval.
Benjamin Rouben, Eleodor Nichita
Nuclear Technology | Volume 207 | Number 10 | October 2021 | Pages 1633-1638
Technical Note | doi.org/10.1080/00295450.2020.1827884
Articles are hosted by Taylor and Francis Online.
Throughout the years, various reports and training manuals on CANada Deuterium Uranium (CANDU) reactors have mentioned that the CANDU lattice is overmoderated. Overmoderation is not always defined in such documents but often appears associated with the positive void reactivity of the CANDU lattice. Some documents refer, logically, to overmoderation as meaning that the lattice pitch is larger than the pitch that maximizes the infinite-lattice multiplication constant but do not demonstrate this is the case for CANDU. We demonstrate that in fact, the CANDU lattice is undermoderated; that is, the current 28.575-cm lattice pitch is smaller than the pitch for which the infinite-lattice multiplication constant reaches its maximum. We hypothesize that the misconception of CANDU overmoderation may have originated from attributing the CANDU positive void reactivity to too much moderator by incorrectly equating the effect of losing heavy water coolant with the effect of losing heavy water moderator.