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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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.
Takashi Kiguchi
Nuclear Science and Engineering | Volume 53 | Number 1 | January 1974 | Pages 112-120
Technical Paper | doi.org/10.13182/NSE74-A23335
Articles are hosted by Taylor and Francis Online.
The modified one-mode method for fast-reactor neutron diffusion calculations was formulated by collapsing two- or three-energy-mode synthesis equations to an effective one-mode equation. The calculational procedure consists of solving an eigenvalue problem to determine the effective neutron multiplication factor and the first-mode expansion coefficient, and solving inhomogeneous problems to determine the higher mode expansion coefficients. Therefore, the computer running time nearly equals that of the conventional one-group eigenvalue problem. The accuracy of this method was investigated by comparing the results obtained by a modified one-mode method with reference 26-group calculations, employing a one-dimensional radial model of a commercial fast breeder reactor. The discrepancies between the modified one-mode method based on three-mode synthesis and the 26-group method are <0.1% in the effective multiplication factor, 5% in the control-rod reactivity and <2% in the power distribution. These results assure the applicability of this method to fast-reactor design studies.
