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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.
Susumu Naito, Makoto Takemura, Shungo Sakurai, Mikio Izumi, Yasushi Goto, Yoshiji Karino
Nuclear Science and Engineering | Volume 166 | Number 2 | October 2010 | Pages 107-117
Technical Paper | doi.org/10.13182/NSE09-99
Articles are hosted by Taylor and Francis Online.
To simplify in-core instrumentation in a next-generation boiling water reactor (BWR), we study an ex-core nuclear instrumentation system. As a first step of this study, we focused on ex-core local power monitoring, which is especially difficult because neutrons inside a core cannot fly out of a reactor pressure vessel (RPV) due to shielding of fuel, water, etc., except when they are generated in the outer edges of the core. To resolve this, we created a local power monitoring method with neutron streaming pipes (NSPs). An NSP is a gas-filled pipe of size comparable to an instrumentation tube of an existing BWR. NSPs are axially inserted into the core. In-core neutrons are transported to the RPV through NSPs. The neutrons transmitted through the RPV are monitored with ex-core neutron sensors. We analytically evaluated the applicability of this NSP method for an advanced BWR (ABWR) with a three-dimensional BWR core simulator and the MCNP5 code. The ex-core neutron flux through the NSP was highly proportional to local power (1.0% of the residual standard deviation). The flux amount and the linearity gave feasible specifications for the ex-core neutron sensor in typical operation modes (pulse, Campbell, and current modes). Therefore, the NSP method is applicable to an ABWR.