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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Shifting the paradigm of supply chain
Chad Wolf
When I began my nuclear career, I was coached up in the nuclear energy culture of the day to “run silent, run deep,” a mindset rooted in the U.S. Navy’s submarine philosophy. That was the norm—until Fukushima.
The nuclear renaissance that many had envisioned hit a wall. The focus shifted from expansion to survival. Many utility communications efforts pivoted from silence to broadcast, showcasing nuclear energy’s elegance and reliability. Nevertheless, despite being clean baseload 24/7 power that delivered a 90 percent capacity factor or higher, nuclear energy was painted as risky and expensive (alongside energy policies and incentives that favored renewables).
Economics became a driving force threatening to shutter nuclear power. The Delivering the Nuclear Promise initiative launched in 2015 challenged the industry to sustain high performance yet cut costs by up to 30 percent.
Garry C. Gose, Thomas J. Downar, Karl O. Ott
Nuclear Technology | Volume 124 | Number 3 | December 1998 | Pages 284-290
Technical Note | Reactor Safety | doi.org/10.13182/NT98-A2927
Articles are hosted by Taylor and Francis Online.
The main-steam-line-break (MSLB) transient in a pressurized water reactor (PWR) is a core overcooling event that can result in a large positive reactivity insertion. In most analyses the shutdown margin is sufficiently large that the core does not return to critical. However, some researchers have reported an increase in the core power even though the core does not return to critical. A simplified kinetics model based on the prompt-jump-kinetics approximation is reported in new work, and a single delayed neutron group is used to explain the core power increase during subcriticality. Specifically, it is shown that the multiplication of the initial delayed-neutron source as predicted by the rate of change of the reactivity during the transient is the reason for the increase in power even though the core never returns to criticality after scram. The results are demonstrated using data from a RETRAN-03 model of a hot-zero-power MSLB analysis of the Three Mile Island unit 1 PWR.
