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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.
Üner Çolak, Volkan Seker
Nuclear Science and Engineering | Volume 149 | Number 2 | February 2005 | Pages 131-137
Technical Paper | doi.org/10.13182/NSE04-17
Articles are hosted by Taylor and Francis Online.
In this study, the criticality analysis for a pebble bed reactor, HTR-10, is performed with Monte Carlo simulations. The MCNP4B code package is utilized in the analysis with ENDF/B-VI continuous energy cross sections. The full core with the initial loading case is considered in simulations. The variation of the effective multiplication factor as a function of core loading height is also analyzed. Three different geometrical models are employed to see the effect of geometrical detail on the criticality calculations. Results are compared with diffusion calculations as well as the experimental data. Results show that the use of the homogenized fuel zone model does not yield acceptable results and underestimates the core criticality. However, the results obtained by using models with uniform and randomly distributed coated fuel particles in the fuel zone are in quite good agreement and there is not any systematic difference. Furthermore, criticality values do not change significantly with different random arrangements of coated fuel particles in fuel spheres. However, the random and irregular arrangements of pebbles may result in statistically different criticality values at least due to varying streaming effect.