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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.
H. Dean Brown, William E. Loewe
Nuclear Science and Engineering | Volume 5 | Number 6 | June 1959 | Pages 376-381
Technical Paper | doi.org/10.13182/NSE59-A25613
Articles are hosted by Taylor and Francis Online.
Temperature coefficients in large reactors can be obtained from the transient response of the flux to oscillations of control rods. A method is described with which the coefficients can be measured under full operating conditions and without special instrumentation or access to the pile. Thus, the technique is particularly useful in measuring the dependence of the coefficients upon hydraulic conditions, power level, and fuel exposure. The waveform of the perturbing oscillation of reactivity is trapezoidal so that the regular reactor control system can be used. In large reactors the flux shape changes during the portion of the cycle when the control rods are moving, but only the magnitude of the flux changes significantly while the control rods are stationary. The flux response during this latter portion of the cycle is analyzed for the temperature coefficients. The pile kinetics equations, coupled with equations for the temperatures of fuel, coolant, and moderator, are solved for the flux during the imposed oscillation. The temperature coefficients and their delay times are found by fitting computed fluxes to the observed flux.
