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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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NECX debut: Shaping the next era of energy
The sold-out inaugural Nuclear Energy Conference & Expo (NECX) got off to a roaring start in Atlanta, Ga., Tuesday morning with an opening plenary that was a live highlight reel discussing the latest industry achievements.
Starting with a lively promo video that left the audience amped up for Entergy’s CEO and NEI chair Drew Marsh, who welcomed everyone to the event, hosted jointly by the American Nuclear Society and the Nuclear Energy Institute. He spoke to a full house of more than 1,300 attendees, promising a blend of science, technology, policy, and advocacy centered around the future of nuclear energy.
Kristin N. Stolte, Jeffrey A. Favorite, George E. McKenzie, Theresa E. Cutler, Jesson D. Hutchinson, Nicholas W. Thompson, Rene G. Sanchez
Nuclear Technology | Volume 208 | Number 4 | April 2022 | Pages 625-643
Technical Paper | doi.org/10.1080/00295450.2021.1945357
Articles are hosted by Taylor and Francis Online.
Kilowatt Reactor Using Stirling TechnologY (KRUSTY) was a prototype for the U.S. National Aeronautics and Space Administration’s Kilopower Program. KRUSTY has a highly enriched uranium–molybdenum alloy (with 7.65 wt% molybdenum) annular core reflected by beryllium oxide with an outer stainless steel shield. Five configurations from the experimental campaign were chosen to be evaluated as benchmark cases. Uncertainties were evaluated in five categories: (1) criticality measurement, (2) mass and density, (3) dimensions, (4) material compositions, and (5) positioning. The largest contribution to the overall uncertainty in each case was from the radial alignment of the movable platen. A simplified model was created to increase computational efficiency, and an average bias of –16 pcm was calculated due to the simplifications. Sample calculations were completed for each case using MCNP6.2, COG, and MC21, all with ENDF/B-VIII.0 nuclear data. For MCNP6.2, the average difference (absolute value) between the calculated and experimental keff for the five configurations was 14 pcm for both the detailed and the simplified models. The keff results from all three codes are within 1σ of the benchmark values. KRUSTY’s value as a benchmark is due to its sensitivity to beryllium and molybdenum. For beryllium, KRUSTY adds an 18th benchmark with a total cross-section sensitivity greater than 0.05%/%/(unit lethargy). For molybdenum, KRUSTY adds a 9th benchmark with a total cross-section sensitivity greater than 0.004%/%/(unit lethargy).