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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
John F. Carew, Gabriel Zamonsky
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 199-207
Technical Paper | doi.org/10.13182/NSE97-83
Articles are hosted by Taylor and Francis Online.
Mechanical quadratures that allow systematic improvement and solution convergence are derived for application of the discrete ordinates method to the Boltzmann transport equation. The quadrature directions are arranged on n latitudinal levels, are uniformly distributed over the unit sphere, and have positive weights. Both a uniform and equal-weight quadrature set UEn and a uniform and Gauss-weight quadrature set UGn are derived. These quadratures have the advantage over the standard level-symmetric LQn quadrature sets in that the weights are positive for all orders, and the solution may be systematically converged by increasing the order of the quadrature set. As the order of the quadrature is increased the points approach a uniform continuous distribution on the unit sphere and the quadrature is invariant with respect to spatial rotations. The numerical integrals converge for continuous functions as the order of the quadrature is increased.Numerical calculations were performed to evaluate the application of the UEn quadrature set. Comparisons of the exact moments and those calculated using the UEn quadrature set demonstrate that the moment integrals are performed accurately except for distributions that are very sharply peaked along the direction of the polar axis. A series of DORT transport calculations of the >1-MeV neutron flux for a typical reactor core/pressure vessel geometry were also carried out. These calculations employed the UEn (n = 6, 10, 12, 18, and 24) quadratures and indicate that the UEn solutions have converged to within ~0.5%. The UE24 solutions were also found to be more accurate than the calculations performed with the S16 level-symmetric quadratures.