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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.
H. S. Khalil, R. N. Hill
Nuclear Science and Engineering | Volume 109 | Number 3 | November 1991 | Pages 221-266
Technical Paper | doi.org/10.13182/NSE91-A23851
Articles are hosted by Taylor and Francis Online.
Systematic analyses of alternative methods for reducing the sodium void worth for plutonium-fueled liquid-metal reactors (LMRs) have been performed. The focus is on core designs of recent interest in the U.S. LMR program, i.e., designs in the 450- to 1200-MW(thermal) size range that make use of metal alloy fuel. The design alternatives encompass changes in composition and geometry. An internally consistent and comprehensive evaluation is made of the void worth reduction achievable by various methods and of the associated core physics performance trade-offs. The performance penalties (e.g., the reduced breeding efficiency and the increases in burnup reactivity loss and fissile mass requirement) caused by design changes that significantly reduce the void worth are quantified, and the relative merits of each design option are assessed. The results indicate that the penalties in burnup reactivity loss and fissile requirement can be minimized by use of a “tightly coupled” radially heterogeneous configuration of minimum volume consistent with fuel rating limits and by adjusting the core height-to-diameter ratio to a value sufficiently small to yield an acceptable void worth. The reactor breeding ratio penalty, however, is minimized by the use of loosely coupled heterogeneous cores or annular cores with a large central blanket zone. Penalties in core radius and volume can be minimized by core composition changes, specifically by replacing a fraction of the fuel (or steel) with sodium or a moderating material.