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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.
D. Meneghetti, H. H. Hummel, W. B. Loewenstein
Nuclear Science and Engineering | Volume 3 | Number 2 | February 1958 | Pages 151-160
Technical Paper | doi.org/10.13182/NSE58-A25457
Articles are hosted by Taylor and Francis Online.
The degradation of neutron energies in a fast reactor is largely due to inelastic scattering. In a dilute fast system (large U238 to U235 atomic ratio) the neutron spectrum is then primarily determined by a fission spectrum distribution modified by inelastic scattering in U238. In this investigation a set of ten-group fast cross sections for U238 have been prepared with the inelastic cross cross sections below about 1.35 Mev based upon levels at 45, 150, and 700 kev. The inelastic transfer contributions from unknown higher levels were chosen to be consistent with the gross measurements of Bethe, Beyster, and Carter, having the three-group energy division consisting of above 1.4 Mev. between 0.4 and 1.4 Mev, and below 0.4 Mev. The ten-group fast cross sections were tested by comparing the calculated equilibrium spectrum, diffusion length, and detector responses in natural uranium with reported experimental values found in the blanket of the Zephyr reactor and in the Snell experiments.
