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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.
Taek Kyum Kim, Chang Hyo Kim
Nuclear Science and Engineering | Volume 123 | Number 3 | July 1996 | Pages 381-391
Technical Paper | doi.org/10.13182/NSE96-A24201
Articles are hosted by Taylor and Francis Online.
A method for determining the mathematical adjoint solution of a higher order nodal expansion method (NEM) based on the simultaneous solution of multigroup equations for each node in the rectangular geometry is presented. In the higher order NEM, the forward NEM equations in a given node include not only the nodal balance and interface-current equations but also weighted residual method (WRM) equations for higher order expansion coefficients. In deriving the mathematical adjoint equations corresponding to these forward NEM equations, the transverse leakage terms in the WRM equations need to be replaced by partial currents. Because transverse leakage terms of a node are linked to partial currents of many neighboring nodes, replacement of transverse leakage terms by partial currents results in complicated WRM equations. Because mathematical adjoint equations are obtained by transposing the nodal forward equations, direct use of these complicated WRM equations makes the numerical computation of the adjoint solution inefficient. This problem is avoided by treating the transverse leakage terms contained in the WRM equations as additional unknowns and by including the equations defining the transverse leakage terms in terms of partial currents into the nodal forward equations. The mathematical adjoint equations are then derived by transposing the resulting nodal forward equations. This adjoint solution method is verified by comparing nodal adjoint fluxes with the fine-mesh VENTURE solution for the International Atomic Energy Agency (IAEA) pressurized water reactor (PWR) benchmark problem and by comparing the local reactivity changes computed with first-order perturbation theory for the IAEA PWR and the Yonggwang unit 2 PWR with the exact reactivity values determined from the eigenvalue difference between perturbed and unperturbed cores.