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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.
R. I. Smith
Nuclear Science and Engineering | Volume 21 | Number 4 | April 1965 | Pages 481-489
Technical Paper | doi.org/10.13182/NSE65-A18792
Articles are hosted by Taylor and Francis Online.
The change in k∞ of a heterogeneous lattice caused by a uniform change in the temperature of the fuel has been measured, using the Physical Constants Testing Reactor (PCTR). The test lattice was moderated with graphite and fueled with concentric-tube elements of slightly enriched uranium metal. The temperature of the fuel was varied from 297 to 1241°K. The change in k∞ with temperature was nonlinear and could be represented by the relation where T is in degrees Kelvin. The experimentally measured values of the constants were α = (−0.308 ± 0.004), β = (−0.120 ± 0.004), γ = (−0.085 ± 0.004). The unit functions, U, represent the changes in k∞ caused by the isothermal volume expansion of the fuel element when the uranium metal undergoes transformations in its crystal structure from alpha to beta and from beta to gamma phases. The term C is a normalization factor related to the lattice under study. The reactivity techniques employed here are shown to be four times more sensitive than activation methods for determining the functional relationship between the effective resonance integral of a fuel element and the temperature of the element. The constant, α, has been experimentally separated into two components: αv = (−0.240 ± 0.04). which is associated with the average interior temperature of the fuel, and αs = (−0.068 ± 0.04), which is associated with the temperature of the surface of the fuel. This separation allows treatment of nonuniform temperature distribution in the fuel.
