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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.
Ziya Akcasu
Nuclear Science and Engineering | Volume 3 | Number 4 | April 1958 | Pages 456-467
Technical Paper | doi.org/10.13182/NSE58-A25482
Articles are hosted by Taylor and Francis Online.
Kinetic equations without the thermal feedback are integrated for an arbitrary reactivity variation, assuming that the magnitude of the changes in the excess reactivity is less than one dollar. First and second approximations are obtained. The results are applied to the step, ramp, and periodical reactivity changes. It is found that the logarithm of the flux, in the first approximation, is given by the function which is the solution of the linearized kinetic equations for the flux. Hence, the usual transfer function approach can be used to form the first approximate solution of the nonlinear kinetic equations. The wave form of the flux is obtained for a sinusoidal input, and the second harmonic is calculated. The exponential rise in the average value, as well as in the amplitude, of the oscillations of the flux is given for an alternative reactivity input. The gain of the reactor is defined. It is shown that the relative gain of the reactor decreases slightly with the increasing amplitude of the sinusoidal input. The results are compared to a numerical solution obtained by AVIDAC.
