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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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A series of firsts delivers new Plant Vogtle units
Southern Nuclear was first when no one wanted to be.
The nuclear subsidiary of the century-old utility Southern Company, based in Atlanta, Ga., joined a pack of nuclear companies in the early 2000s—during what was then dubbed a “nuclear renaissance”—bullish on plans for new large nuclear facilities and adding thousands of new carbon-free megawatts to the grid.
In 2008, Southern Nuclear applied for a combined construction and operating license (COL), positioning the company to receive the first such license from the U.S. Nuclear Regulatory Commission in 2012. Also in 2008, Southern became the first U.S. company to sign an engineering, procurement, and construction contract for a Generation III+ reactor. Southern chose Westinghouse’s AP1000 pressurized water reactor, which was certified by the NRC in December 2011.
Fast forward a dozen years—which saw dozens of setbacks and hundreds of successes—and Southern Nuclear and its stakeholders celebrated the completion of Vogtle Units 3 and 4: the first new commercial nuclear power construction project completed in the U.S. in more than 30 years.
Keiichi Mochizuki, Atushi Takeda
Nuclear Science and Engineering | Volume 7 | Number 4 | April 1960 | Pages 336-344
Technical Paper | doi.org/10.13182/NSE60-A25727
Articles are hosted by Taylor and Francis Online.
Neutron flux spatial oscillation due to xenon build-up in the reactor core is a well-known characteristic of large power reactors. Especially a reactor with a positive temperature coefficient of reactivity tends to have such a characteristic. In this paper, the analysis has been pursued on a Calder Hall type reactor. Specific features to be taken into consideration were a large neutron flux flattened zone in the core and a graphite sleeve in each coolant channel. First, the threshold values of the temperature coefficient for initiating oscillation of successive orders of modes in radial and azimuthal directions as well as oscillation periods have been calculated. Secondly, the effect of the sleeve on threshold value and oscillation period has been investigated. Thirdly, in order to clarify this phenomenon, a vector analysis has been made which helps us to understand the critical condition for initiating the oscillation as well as the relation between effects of neutron leakage, temperature coefficients of fuel and moderator, and xenon poisoning. Finally, taking advantage of the transfer function defined in each mode, the spatial control method could be analyzed without using a spatial simulator.
