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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.
R. van Geemert, F. Tani
Nuclear Science and Engineering | Volume 149 | Number 1 | January 2005 | Pages 74-87
Technical Paper | doi.org/10.13182/NSE05-A2478
Articles are hosted by Taylor and Francis Online.
A methodology is presented that allows a higher-order accurate treatment of system perturbations that are assumed to have a substantial magnitude and therefore also a substantial effect on flux distributions in nuclear systems. Examples are localized material choice variations, burnable poison density variations at lattice level, complete fuel assembly permutations at core level, or specific uncertainties defined in the system composition. For these cases, it is necessary to raise the accuracy of the estimated responses above what can be achieved using first-order perturbation methods only, of course preferably without having to simply pursue computationally expensive exact recalculations for each case if the effects of many variations or uncertainties are to be assessed. Focusing on the neutronics of multiplying systems (without thermal-hydraulic feedback mechanisms incorporated), the setup of a polynomial form for quantification of the flux shape change due to imposed system perturbations is pursued. In a mathematical sense, this method allows one to set up a polynomial expansion of the change in the lowest-mode solution of the neutronics eigensystem due to an imposed perturbation in the operators determining the lowest-mode solution and eigenvalue. This form features the property that the flux shape change, caused by variations in certain parameters localized in space and energy, can be expanded polynomially up to higher-order accuracy, with the imposed system composition variations themselves as functional arguments. Numerical results, showing the validity of the method, are reported, and possible application areas are discussed.