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NN Asks: Is the U.S. ready for nuclear construction to accelerate?
Craig Stover
Yes, but . . .
The United States is better positioned today for nuclear construction than it has been in decades. Some of that comes from the experience gained at Vogtle and V.C. Summer. I was part of the team that helped start the V.C. Summer project in 2008, and at that time we were trying to build a nuclear construction workforce from scratch. We learned a lot through that effort, and many of those lessons learned have since been studied, documented, and shared.
The nuclear industry is also benefiting from the wave of investment that started growing around 2020. Over the last five or six years, there has been a serious effort across the country to get ready for new nuclear builds. The U.S. government and the private sector are investing billions of dollars in new nuclear. Much of that work is happening before widespread commercial deployment contracts are signed. This is real, and we need to prepare.
Lanfranco Monti, Ki-Bog Lee, Massimiliano Fratoni, Marco Sumini, Ehud Greenspan
Nuclear Science and Engineering | Volume 161 | Number 1 | January 2009 | Pages 1-21
Technical Paper | doi.org/10.13182/NSE162-01
Articles are hosted by Taylor and Francis Online.
The feasibility of indefinite recycling in the Encapsulated Nuclear Heat Source (ENHS) core without changing the pitch-to-diameter (P/D) ratio, while maintaining a nearly zero burnup reactivity swing, is investigated. The P/D ratio required to achieve a nearly burnup-independent keff over the life of the ENHS core was found sensitive to the initial composition of the transuranium (TRU) loaded and to the number of recycles this fuel underwent. The longer the cooling time is of the TRU from light water reactor (LWR) spent fuel, the larger the optimal P/D ratio becomes. Whereas the optimal P/D ratio of the reference ENHS core that is fueled with TRU from LWR spent fuel discharged at 50 GWd/t heavy metal (HM) and cooled for 10 yr is 1.36, it is 1.54 for the equilibrium core that features a substantially smaller concentration of 241Pu as well as of 242Pu, a larger concentration of 239Pu, and a substantially larger concentration of minor actinides. It was found that by increasing the cooling period of the above LWR TRU to ~32 yr, the optimal first core P/D ratio is that of the equilibrium core. The burnup reactivity swing of the subsequent cores fueled with successive recycling of the ENHS discharged HM is satisfactory. There is no need to adjust the core P/D ratio from recycle to recycle. The power level that can be removed by natural circulation from the P/D = 1.54 core is ~36% higher than that of the reference ENHS core. The physical phenomena affecting the observed trends are discussed, and the neutronic characteristics of the equilibrium cores identified are summarized.
