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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The journey of the U.S. fuel cycle
Craig Piercycpiercy@ans.org
While most big journeys begin with a clear objective, they rarely start with an exact knowledge of the route. When commissioning the Lewis and Clark expedition in 1803, President Thomas Jefferson didn’t provide specific “turn right at the big mountain” directions to the Corps of Discovery. He gave goal-oriented instructions: explore the Missouri River, find its source, search for a transcontinental water route to the Pacific, and build scientific and cultural knowledge along the way.
Jefferson left it up to Lewis and Clark to turn his broad, geopolitically motivated guidance into gritty reality.
Similarly, U.S. nuclear policy has begun a journey toward closing the U.S. nuclear fuel cycle. There is a clear signal of support for recycling from the Trump administration, along with growing bipartisan excitement in Congress. Yet the precise path remains unclear.
Zhiwen Xu, Yasuyuki Otsuka, Pavel Hejzlar, Mujid S. Kazimi, Michael J. Driscoll
Nuclear Technology | Volume 160 | Number 1 | October 2007 | Pages 63-79
Technical Paper | Annular Fuel | doi.org/10.13182/NT07-A3884
Articles are hosted by Taylor and Francis Online.
Compared to the traditional solid fuel pin, annular fuel with internal as well as external coolant flow increases the cooling surface by ~50%, which allows a higher core power density. However, operating at high power density introduces challenges in the core physics design of burnable poison to suit the desired fuel cycle length. In this paper, both the fuel cycle length and the number of reload fresh fuel assemblies are assumed to remain the same as current industry practice (18-month cycle and three-batch fuel management), which in turn requires >5 wt% fuel enrichment for the 150% power core. Alternative fuel cycles are discussed. Pressurized water reactor cores with annular fuel are designed using the state-of-the-art Studsvik Scandpower core modeling package including CASMO-4, TABLES-3, and SIMULATE-3. Two power levels are considered for the core design based on annular fuel: 100 and 150% of the rated power. The reactivity feedback effects of the annular fuel are shown to be comparable to those of solid fuel. The 150% power core with annular fuel shows considerable resemblance to traditional high-energy cores.