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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
J. González, P. Zanocco, M. Giménez, M. Schivo, O. Mazzantini, M. Caputo, G. Bedrossian, P. Serrano, A. Vertullo
Nuclear Technology | Volume 171 | Number 1 | July 2010 | Pages 14-26
Technical Paper | Reactor Safety | doi.org/10.13182/NT10-A10769
Articles are hosted by Taylor and Francis Online.
This paper presents a model of the Atucha Unit II pressurized heavy water reactor nuclear power plant (currently in the final construction stage) developed in RELAP5/MOD3.3. The nodalization was implemented in order to comply with the probabilistic safety analysis required in the licensing, commissioning, and operating process.The reactor is cooled and moderated by heavy water. Though the primary circuit is equivalent to a two-loop pressurized water reactor, the reactor core consists of vertical channels surrounded by a relatively large volume of heavy water acting as a moderator. This moderator is cooled by an independent system and kept at the same pressure but lower temperature than the primary circuit.The relevant components and systems of the plant are presented and nodalized. The main characteristics of the plant are discussed to achieve a correct representation of the expected physical behavior. Additionally, an integral platform of data management is implemented that processes the geometric and physical data for nodalization and finally generates the code input. Then, a complete tracking of data is possible from the corresponding referenced report to the input deck. This tool facilitates the quality assurance process by independent reviewers. Moreover, the verification of sources and documentation employed can be easily implemented.Initially, the steady state is analyzed by comparing variables obtained with the model with their respective design values and previous calculations performed with other models. Finally, a case of loss of heat sink caused by an electrical supply failure is analyzed. Relevant aspects of the plant dynamic are analyzed and presented for this case. The standard procedure established in the plant to tackle this initiating event is also discussed considering the triggered signals and the configurations of the main systems.