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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.
M. J. Nowak
Nuclear Science and Engineering | Volume 4 | Number 1 | July 1958 | Pages 25-43
Technical Paper | doi.org/10.13182/NSE58-A25517
Articles are hosted by Taylor and Francis Online.
A general formulation of the critical reactor equations is made to include space and velocity variation; the noncritical reactor is treated by using the effective multiplication factor. Two methods are developed for solving the general equation by splitting it into a pair of simultaneous equations: the space-energy split and the fission source split. By using unit sources one equation can be inverted to obtain a pair of integral equations for iterative solution of the general equation. The meaning of neutron importance and the physical picture associated with the concept are given. By using its physical meaning the importance balance equation, which is adjoint to the neutron flux equation, is derived by several methods. Neutron importance is used to formulate the change in reactor power produced by a change in reactor parameters. The effective multiplication factor and reactivity are introduced; the perturbation equation for reactor power change is developed in terms of reactivity. The necessary assumptions to derive the diffusion approximation are given, and the general diffusion equation with continuous energy dependence is obtained. From this the multigroup diffusion equations can be obtained, including the multigroup diffusion perturbation equations. The same methods used for the general critical reactor equation are applied to the diffusion equation to obtain its solution by splitting it into a pair of coupled integral equations. The integral equation for the effective multiplication factor is developed in terms of the fission source variable, and a stationary variational formula obtained for estimating the effective multiplication factor.
