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Donalds, Barnard call for streamlining NRC’s regulatory process
“To be frank, any emissions-related climate goals are moonshots without nuclear energy, and next-generation nuclear technology is something that the United States can and SHOULD lead on.” So writes U.S. Rep. Byron Donalds (R., Fla.) and Christopher Barnard, vice president of external affairs for the American Conservation Coalition, in an essay published by RealClear Energy.
Good news: Donalds, one of the strongest advocates for nuclear energy in the U.S. House, and Barnard, publisher and coauthor of Green Market Revolution, begin their essay by noting some recent positive developments for nuclear power. They characterize the initial criticality of Vogtle-3, the first new nuclear reactor built in the United States in about 30 years, as “a monumental achievement for the American nuclear industry.” They praise the Biden administration’s allocation of funds to keep established nuclear plants operational.
Edward W. Larsen
Nuclear Science and Engineering | Volume 197 | Number 2 | February 2023 | Pages 145-163
Technical Paper | doi.org/10.1080/00295639.2022.2058847
Articles are hosted by Taylor and Francis Online.
In this paper, the standard multigroup neutron diffusion equations are derived as an asymptotic approximation to the multigroup neutron transport equations. The asymptotic analysis employs a scaling that (1) is suggested by the multigroup neutron diffusion equations themselves and (2) generalizes the long-known asymptotic scaling for monoenergetic transport problems. Two other asymptotic scalings of the multigroup transport equations are also considered, both of which lead to a new “group-collapsed” (monoenergetic) “equilibrium” diffusion approximation. The standard multigroup and equilibrium diffusion approximations are shown to preserve certain nonasymptotic properties of the multigroup transport equations. Generalizations of the analyses in this paper, and possible practical applications, are discussed.