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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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U.S. nuclear supply chain: Ready for liftoff
Craig Piercycpiercy@ans.org
This month, September 8–11, the American Nuclear Society is teaming up with the Nuclear Energy Institute to host our first-ever Nuclear Energy Conference and Expo—NECX for short—in Atlanta. This new meeting combines ANS’s Utility Working Conference and NEI’s Nuclear Energy Assembly to form what NEI CEO Maria Korsnick and I hope will be the premier nuclear industry gathering in America.
We did this because after more than four decades of relative stagnation, the U.S. nuclear supply chain is finally entering a new era of dynamic growth. This resurgence is being driven by several powerful and increasingly durable forces: the explosive demand for electricity from artificial intelligence and data centers, an unprecedented wave of public and private acceptance of—and investment in—advanced nuclear technologies, and a strong market signal for reliable, on-demand power. Add the recent Trump administration executive orders on nuclear into the mix, and you have all the makings of an accelerant-rich business environment primed for rapid expansion.
Dmitry V. Paramonov, Mohamed S. El-Genk
Nuclear Technology | Volume 117 | Number 1 | January 1997 | Pages 1-14
Technical Paper | Fission Reactor | doi.org/10.13182/NT97-A35332
Articles are hosted by Taylor and Francis Online.
The Soviet-made TOPAZ-II space nuclear power system unit designated Ya-21u underwent a total of 15 tests both in the Union of Soviet Socialist Republic (USSR) (1989–1990) and in the United States (August 1993 to March 1995) for a cumulative test/operation time of 7681 h at conditions far exceeding design limits. These tests included steady-state operation at different power levels, fast start-ups and power optimizations, and shock and vibration tests. Test results are presented and analyzed. Results indicate a gradual change in the performance parameters such as the optimum cesium pressure and optimum load voltage. The electric power and conversion efficiency of the unit at an input thermal power of 105 kW decreased from 3.7 kW(electric) and 4% in the test in the USSR to 2.13 kW(electric) and 2.3 % in the last test in the United States. A discussion and qualitative assessment of potential causes of the performance changes of the Ya-21u unit are given.
