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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.
A. H. Spano
Nuclear Science and Engineering | Volume 19 | Number 2 | June 1964 | Pages 172-186
Technical Paper | doi.org/10.13182/NSE64-A28906
Articles are hosted by Taylor and Francis Online.
A calculational model for the Doppler reactivity feedback in a thermal, low-enrichment oxide core with non-uniform temperature distribution is derived on the basis of the UO2 resonance integral varying as the square root of the absolute temperature. An analytical solution of the prompt-approximation, space-independent neutron kinetic equation, with the Doppler feedback written as a function of the fission energy, is obtained and application made to the self-limiting power-excursion tests conducted in the SPERT I oxide core. Comparison of the experimental and calculated Doppler effects, peak powers, burst energies and burst shapes is made for various published values of the UO2 resonance integral temperature coefficient, which acts as a scaling factor in the calculations. The values used cover a spread of about 20% of the mean value, and excellent agreement with experiment is obtained for the smallest values of the coefficient. Systematic agreement is obtained between the calculated and experimental Doppler effects over the entire experimental range of adiabatic fuel-temperature rises attained in the short-period SPERT tests. This agreement implies the validity of a square-root temperature dependence for the Doppler effect in a thermal oxide core, in contrast with a logarithmic or a T 1/2 dependence, for which similar calculations give results which differ significantly from the experimental data.