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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
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.
Takeo Nishigori
Nuclear Science and Engineering | Volume 108 | Number 4 | August 1991 | Pages 347-354
Technical Paper | doi.org/10.13182/NSE91-A23834
Articles are hosted by Taylor and Francis Online.
The effect of a reactivity insertion in a point reactor is formulated as a linear feedback process, and a simple exponential mode representation is proposed as an analytical solution that is valid at small times. The solution contains a fast transient mode as well as slow ones, and it resolves the stiffness problem in a very simple way. With a ramp reactivity insertion as an example, it is shown that this analytical solution is valid for a time interval that is much longer than the time-step size used in the conventional numerical integration, and it is thus useful in reducing computing time.
