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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
T. Auerbach
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 317-324
Technical Paper | doi.org/10.13182/NSE67-A17279
Articles are hosted by Taylor and Francis Online.
In the theory described in this paper, the lattice of a critical or subcritical system is represented by an array of finite cylindrical elements, arbitrarily distributed throughout a cylindrical volume of moderator. The flux in each element is determined from multigroup PN theory, whose asymptotic part in the moderator, i.e., that part of the flux which survives in the moderator at distances of a few mean-free-paths from the element, can readily be identified. The PN-corrected multigroup diffusion equation is solved in the moderator, taking full account of lattice geometry. It is then connected to the asymptotic part of the interior PN solution across each individual element-to-moderator interface. Thus the physical requirement that the angular neutron distribution be continuous across all interfaces is satisfied throughout the lattice. A similar approach is employed to make the distribution continuous across the moderator-to-reflector boundary. The theory yields, as do all heterogeneous theories, a neutron spectrum which changes continuously, both radially and azimuthally, across the lattice. The method is consistent in that it determines fuel characteristics in accordance with this changing spectrum without the need for defining cells or extrapolation lengths.