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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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
Nano Nuclear wins Air Force contract for Kronos MMR
New York City–based advanced nuclear technology developer Nano Nuclear Energy has been awarded a Direct-to-Phase II Small Business Innovation Research contract for its Kronos micro modular reactor (MMR) by AFWERX, the innovation and venture arm of the U.S. Air Force. The contract calls for AFWERX, with the 11th Civil Engineering Squadron, to explore the feasibility of deploying the Kronos MMR Energy System at Joint Base Anacostia-Bolling (JBAB) in Washington, D.C.
José N. Reyes, Jr.
Nuclear Technology | Volume 178 | Number 2 | May 2012 | Pages 153-163
Technical Paper | Small Modular Reactors / Thermal Hydraulics | doi.org/10.13182/NT12-A13556
Articles are hosted by Taylor and Francis Online.
The extreme events that led to the prolonged electrical power outage and finally to sever damage of four units of the Fukushima nuclear plant have highlighted the importance of ensuring a technical means for stable, long-term cooling of the nuclear fuel and the containment following a complete station blackout. This paper presents an overview of the advanced passive safety systems designed for the NuScale nuclear power plant and their role in addressing extreme events. The NuScale plant may include up to 12 power modules, and each module incorporates a reactor pressure vessel (core, steam generator, and pressurizer) and a containment vessel that surrounds the reactor vessel. During normal operation, each containment vessel is fully immersed in a water-filled, stainless steel-lined concrete pool that resides underground. The pool, housed in a Seismic Category I building, is large enough to provide 30 days of core and containment cooling without adding water. After 30 days, the core decay heat generation is so small that the natural convection heat transfer to air at the outside surface of the containment, coupled with thermal radiation heat transfer, are completely sufficient to remove the core decay heat for an unlimited period. These passive safety systems can perform their function without requiring an external supply of water or electric power. Computational and experimental assessments of the NuScale passive safety systems are being performed at several institutions, including the one-third scale NuScale integral system test facility at Oregon State University.