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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.
William M. Grim, Jr., Bruce B. Barrow, John C. Simons, Jr.
Nuclear Science and Engineering | Volume 1 | Number 1 | March 1956 | Pages 80-91
Technical Paper | doi.org/10.13182/NSE56-A17660
Articles are hosted by Taylor and Francis Online.
Measurement of reactor period at low power levels (from 10-10 to 10-5 of full power) during start-up is desirable to permit the full power level to be reached rapidly yet safely. At low flux levels, it is natural to attempt to obtain period information by differentiating the output of a logarithmic counting-rate meter. Because of the random arrival of pulses at the input of the system, however, the period indicated at the output will fluctuate about the correct value, the magnitude of the fluctuation depending upon the average counting rate and upon the system parameters. If the diode in the logarithmic circuit is replaced for incremental analysis by an appropriate linear resistor, the magnitude of the output fluctuations can be calculated by applying shot noise theory. These calculations are here carried out for the infinite-period case (constant counting rate), using the counting rate as an independent variable. Experiments were carried out, and the results agreed closely with theory. Although the present study is based on fluctuations occurring when flux is held constant, other work shows the results to be applicable also to flux transients.
