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Orlando, FL|Renaissance Orlando at SeaWorld
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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.
Yoshitomo Uwamino, Takashi Nakamura, Kazuo Shin
Nuclear Science and Engineering | Volume 80 | Number 3 | March 1982 | Pages 360-369
Technical Paper | doi.org/10.13182/NSE82-A19820
Articles are hosted by Taylor and Francis Online.
Attenuation of neutrons and photons transmitted through graphite, iron, water, and ordinary concrete assemblies were studied by spectral measurements using an NE-213 organic scintillation detector with an (n-γ) discrimination technique. Source neutrons and photons were produced by 52-MeV proton bombardment of a 21.4-mm-thick graphite target placed in front of the assembly. The distributions of the light output from the scintillator following activation by neutrons and photons were unfolded by the revised FERDO code. These experimental results were used as benchmark data on neutron and photon penetration by neutrons of energy above 15 MeV. Multigroup Monte Carlo and one-dimensional ANISN transport calculations were performed with the DLC-58/HELLO group cross sections to compare with the measurement and to evaluate the cross sections. The results of the ANISN calculation of neutrons in slab geometry and the three-dimensional Monte Carlo calculation agreed with the experimental values except for high energy neutrons transmitted through water and graphite. The agreement of both calculations was well within the accuracy of 7% in the measured attenuation coefficients for graphite, iron, and water, and <10% for concrete. For photons, the ANISN calculation gave >20% over-estimation of the attenuation coefficients in the case of deep penetration through the medium for which the photon mean-free-path is shorter than that of neutrons, such as in iron and concrete. The secondary photons produced by the neutron-nucleus reactions are dominant compared with the primary photons, but otherwise the ANISN calculations gave good results.