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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.
J. J. Rush, G. J. Safford, T. I. Taylor, W. W. Havens, Jr.
Nuclear Science and Engineering | Volume 14 | Number 4 | December 1962 | Pages 339-345
Technical Paper | doi.org/10.13182/NSE62-A26240
Articles are hosted by Taylor and Francis Online.
Recent neutron cross-section measurements have shown that certain ammonium salts and methyl substituted compounds may be useful as moderators for cold neutron sources. In the present experiments slow-neutron total cross sections for polycrystalline NH4PF6, (NH4)2S2O8, and (NH4)2CrO4 have been measured at 80°K and 296°K as a function of neutron wavelength. In addition cross sections have been measured at 23°C for NH4SO3F and CH3C≡CCH3. Cross sections vs. temperature for NH4PF6 and (NH4)2S2O8 were also obtained at λn = 8 A (0.0015 ev) from 80°K to room temperature. The long-wavelength slopes in b/A of the scattering cross sections per hydrogen atom at 23°C are: NH4PF6, 12.7; (NH4)2S2O8, 9.6; NH4SO3F, 10.0; (NH4)2CrO4, 5.5; CH3C≡CCH3, 12.4. The slope for NH4PF6 approaches that for free NH3 gas indicating a rotational barrier of ∼0.2 kcal/mole for the ammonium ion. The high slope for CH3C≡CCH3 indicates a low barrier to rotation of the methyl groups in this compound. The lower slopes for (NH4)2S2O8 and NH4SO3F show that the ammonium ions in these compounds have higher barriers of the order of O.7 to 1 kcal/mole. Slopes measured at 80°K are: NH4PF6, 2.5 b/A-H; (NH4)2S2O8, 1.0 b/A-H; (NH4)2CrO4, 0.0 b/A-H. In addition the cross section vs. temperature curve for NH4PF6 indicates no abrupt change in rotational barrier down to 80°K. These low-temperature results show the presence of significant rotational freedom in NH4PF6 even at 80°K. The presence of rotational states at low temperature for exchange of energy with neutrons, together with the comparatively low absorption cross sections, make ammonium salts such as NH4PF6 (N15 enriched) and methyl substituted compounds like CH3C≡CCH3 of interest as moderators for cold neutron sources.
