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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.
MARK NELKIN
Nuclear Science and Engineering | Volume 2 | Number 2 | April 1957 | Pages 199-212
Technical Paper | doi.org/10.13182/NSE57-A25387
Articles are hosted by Taylor and Francis Online.
The energy distribution of neutrons thermalized in an infinite homogeneous medium containing a crystalline moderator and absorbing material is investigated with the aid of a simplified model of the crystal. A Debye phonon spectrum is assumed, and a formal expansion in powers of the ratio of neutron mass to moderator atom mass is used. The inelastic scattering is approximated by the term of first order in the mass ratio, and interference effects are neglected. The resulting energy-change kernel is not correct in detail at high energies, but it correctly gives the average logarithmic energy loss, and therefore can be used in the age theory approximation at energies well above thermal. Solutions of the integral equation for the energy spectrum have been obtained on the IBM-650 for (1/υ) absorption. These are compared to solutions of the differential equation for a heavy gaseous moderator. It is found that the thermal spectra are very insensitive to the choice of scattering model, even when large departures from thermal equilibrium occur.
