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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
IAEA again raises global nuclear power projections
Noting recent momentum behind nuclear power, the International Atomic Energy Agency has revised up its projections for the expansion of nuclear power, estimating that global nuclear operational capacity will more than double by 2050—reaching 2.6 times the 2024 level—with small modular reactors expected to play a pivotal role in this high-case scenario.
IAEA director general Rafael Mariano Grossi announced the new projections, contained in the annual report Energy, Electricity, and Nuclear Power Estimates for the Period up to 2050 at the 69th IAEA General Conference in Vienna.
In the report’s high-case scenario, nuclear electrical generating capacity is projected to increase to from 377 GW at the end of 2024 to 992 GW by 2050. In a low-case scenario, capacity rises 50 percent, compared with 2024, to 561 GW. SMRs are projected to account for 24 percent of the new capacity added in the high case and for 5 percent in the low case.
Yukio Ishiguro
Nuclear Science and Engineering | Volume 51 | Number 4 | August 1973 | Pages 512-514
Technical Note | doi.org/10.13182/NSE73-A23281
Articles are hosted by Taylor and Francis Online.
The intermediate resonance approximation of resonance absorption is applied to a heterogeneous fast reactor assembly to see how each resonance of 238U deviates from the narrow resonance approximation. The resonance integral is calculated for the 50 resonances of 238 U in ENDF/B-II below 1.9 keV. The averaged deviation of these resonances from the narrow resonance extreme was found to be ∼4%. It is concluded that the effective group cross sections in heterogeneous fast systems can be estimated reasonably well by the narrow resonance approximation, even though this approximation tends to underestimate the resonance integrals noticeably for a handful of resonances with extremely large neutron widths.
