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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.
Michel Mélice
Nuclear Science and Engineering | Volume 37 | Number 3 | September 1969 | Pages 451-477
Technical Paper | doi.org/10.13182/NSE69-A19119
Articles are hosted by Taylor and Francis Online.
This paper presents a new attempt towards the development of a systematic method for solving the fuel cycling management optimization problem in modern PWR cores. When the infinite multiplication factor k is used as a single variable to describe the fuel distribution over the core at any stage of its life, the analysis of any reloading pattern can be performed on the basis of its corresponding k-map in the X-Y plane, or more simply, on the basis of its equivalent “k-profile” in cylindrical geometry. Conversely, it is shown how the reloading pattern can be synthesized from the k-profile, which becomes, therefore, the main tool of the method. The search for the best k-profile rests on the analysis of the necessary relations existing, for any particular reloading mode (batch, multiregion, salt-and-pepper, etc.) between the k-profiles and cycle times, and on the use of a cycle “internal optimality condition” aiming to maximize the reactivity of the reloading k-profile, and consequently, the cycle life time, with a constraint on the power-peak factor. As a result, the general many-variable cycling problem can be contracted into a single control-variable problem which, in turn, can be separated into the following two simpler tasks: a cycle internal optimization problem consisting of finding the reloading mode and the single control variable which minimize the stationary cycle cost and a cycle external optimization problem aiming to minimize the cost penalty associated with any deviation of the cycling sequence from the optimal stationary cycle. Using the particular class of optimal k-profiles complying with the maximum power (minimum peak factor) condition, the method is applied to the analysis of the stationary and transient cycles of the SENA reactor, with the three-region mixed reload mode. The methods for calculating the optimal profile classes corresponding to an arbitrary peak factor are also indicated.