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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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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.
Sten-Örjan Lindahl
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 475-478
Technical Note | doi.org/10.13182/NSE74-A23378
Articles are hosted by Taylor and Francis Online.
Using the multigroup diffusion equation, a reciprocity relation is established for an arbitrarily shaped body. This relation expresses the flux caused by a source inside the body in terms of the flux resulting from an incident current on that body. In the multigroup case for one-dimensional bodies with flat sources and in the one-group case for rectangular two-dimensional bodies with an arbitrary source, practical formulas are derived from this relation. These give the leakage from a body in terms of its reflection and transmission properties. An advantage of the use of this reciprocity relation is the improved computational efficiency in response matrix calculations.
