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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Orlando, FL|Renaissance Orlando at SeaWorld
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
E. E. Lewis, G. Palmiotti
Nuclear Science and Engineering | Volume 130 | Number 2 | October 1998 | Pages 181-193
Technical Paper | doi.org/10.13182/NSE98-A1999
Articles are hosted by Taylor and Francis Online.
Red-black algorithms for solving response matrix equations in one- and two-dimensional diffusion theory are examined. The definition of the partial currents in terms of the scalar flux and net currents is altered to introduce an acceleration parameter that modifies the values of the response matrix elements while leaving the flux and net current solutions unchanged. The acceleration parameter is selected for response matrices derived analytically for slab geometry and from the variational nodal method for both slab and x-y geometries to minimize the spectral radius of the red-black iteration matrix for homogeneous media. The optimal value is shown to be independent of the mesh spacing in the fine mesh limit and to be a function only of c, the scattering-to-total cross section ratio. The method is then generalized to treat multiregion problems by formulating an approximate expression for the optimum acceleration parameter and demonstrated for a series of benchmark diffusion problems.