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Atlanta, GA|Atlanta Marriott Marquis
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From operator to entrepreneur: David Garcia applies outage management lessons
David Garcia
If ComEd’s Zion plant in northern Illinois hadn’t closed in 1998, David Garcia might still be there, where he got his start in nuclear power as an operator at age 24.
But in his ninth year working there, Zion closed, and Garcia moved on to a series of new roles—including at Wisconsin’s Point Beach plant, the corporate offices of Minnesota’s Xcel Energy, and on the supplier side at PaR Nuclear—into an on-the-job education that he augmented with degrees in business and divinity that he sought later in life.
Garcia started his own company—Waymaker Resource Group—in 2014. Recently, Waymaker has been supporting Holtec’s restart project at the Palisades plant with staffing and analysis. Palisades sits almost exactly due east of the fully decommissioned Zion site on the other side of Lake Michigan and is poised to operate again after what amounts to an extended outage of more than three years. Holtec also plans to build more reactors at the same site.
For Garcia, the takeaway is clear: “This industry is not going away. Nuclear power and the adjacent industries that support nuclear power—and clean energy, period—are going to be needed for decades upon decades.”
In July, Garcia talked with Nuclear News staff writer Susan Gallier about his career and what he has learned about running successful outages and other projects.
Keisuke Kobayashi, Hiroshi Nishihara
Nuclear Science and Engineering | Volume 28 | Number 1 | April 1967 | Pages 93-104
Technical Paper | doi.org/10.13182/NSE67-A18671
Articles are hosted by Taylor and Francis Online.
The group-diffusion equation in one-dimensional geometry is solved by using Green's function. In the first section, using Green's tensor, the group-diffusion equation is transformed into a system of linear equations which contain only the fluxes at the interfaces between the regions. Solving this equation, we obtain the fluxes at the interfaces and then the flux inside the regions with the aid of Green's tensor. This treatment is the same kind of approach as that of the response matrix method or the theory of invariant imbedding. In the second section, the group-diffusion equation is solved by the source iteration method. Using Green's function, the exact three-point difference equation is obtained and the explicit forms for the slab, cylindrical, and spherical geometry are given. It is shown that the usual three-point difference equation is obtained if the source term is approximated to be flat piecewise and if Green's function is expanded into Taylor's series neglecting all but the first two terms. Sample calculations for a thermal and a fast reactor show that the improved difference equation obtained by approximating the source term by a polynomial of second degree is more accurate than the usual three-point difference equation.
