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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.
Giovanni Maronati, Bojan Petrovic
Nuclear Technology | Volume 207 | Number 1 | January 2021 | Pages 1-18
Technical Paper | doi.org/10.1080/00295450.2020.1738829
Articles are hosted by Taylor and Francis Online.
Credibility requires predictability. Nuclear power plant (NPP) construction projects tend to be large and expensive, sometimes with high cost overruns far beyond those that might have been expected or predicted due to usual and recognized uncertainties and variations (e.g., in labor and materials costs combined with multiyear duration and complex construction logistics). This unaccounted for uncertainty brings the credibility of new NPP build projects into question and may prevent future projects from going forward. It is believed that the high initial capital cost of nuclear power is less of a hindering factor than the uncertainty about that cost. For nuclear power to regain credibility and enable future NPP construction projects, this unexpected uncertainty, or unknown unknown, needs to be assessed. Regular (expected) uncertainties (known unknowns) were addressed previously in a paper where the Iman-Conover method was used to account for correlated uncertainties. This paper addresses the impact of unexpected events (unknown unknowns), such as the Three Mile Island Unit 2 (TMI-2) accident. For this purpose, NPP construction in the United States is divided into two periods: pre-1979 (NPPs completed before the 1979 TMI-2 accident), and post-1979 (NPPs under construction when the accident happened and completed later). The latter group experienced significant schedule and budget overruns due to the change in regulation imposed after NPP construction was already under way. Analyzed a posteriori, this event and the escalated cost for the second group of NPPs was used to study the impact of a representative unexpected event.
An approach was developed to assess the range of potential risks, including those due to such unexpected events, and thus enable assigning appropriate contingencies. A traditional large four-loop pressurized water reactor [PWR12-Better Experience (BE)] was considered. With the inputs derived from the pre-1979 data, the expected total capital investment cost (TCIC) mean value for the PWR12-BE is found to be $3.3 billion, with a contingency of $1.3 billion, which corresponds to 39.4% of the TCIC mean. If the unknown unknowns are taken into account based on the post-1979 data, the TCIC mean value increases to $9.4 billion, with a cost contingency that is 108% of the TCIC mean derived for the pre-1979 NPPs.
Based on the experience-based assumed probability of unexpected events with large financial impact, it is then possible to derive an adequate contingency. The presented analysis offers a possible approach to treat unknown unknowns and to assess their impact on cost, providing the required contingency, as well as uncertainty in the construction time. In a broader context, this may provide quantitative tools to support making long-term energy policy decisions of new considered nuclear power projects.
