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September 8–11, 2025
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.
W. Ciechanowicz, K. O. Solberg
Nuclear Science and Engineering | Volume 36 | Number 3 | June 1969 | Pages 361-371
Technical Paper | doi.org/10.13182/NSE69-A18734
Articles are hosted by Taylor and Francis Online.
The scope of the paper was to theoretically check the compromise in the control-strategy design to decrease the required number of computations. Two types of HBWR control system models have been investigated: one involves the control-strategy calculation for the overall dynamic system; in the other case, the overall system has been split into two systems characterized by smaller number of state variables. The interactions between the split systems have been included by use of crosscoupling controller elements. The comparison between considered control models has shown similar dynamic behavior of the investigated state variables. The main advantage of splitting the system is decreasing the order of state vectors taken into account in the control-strategy calculations. The constraint problem has been considered by making use of Lagrange multiplier formalism and when the physical amplitude limitations are imposed on the controller signals. The comparison of both types of constraints has shown that the latter is quite satisfactory simplification in the constraint problem of the controller signals. The advantage of applying the physical limitation of the controller signal amplitude is that this type of constraint does not require the computer memory capacity for storage of the optimum trajectory space.