ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Mar 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
March 2026
Nuclear Technology
February 2026
Fusion Science and Technology
April 2026
Latest News
NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
Gregory A. Johnson
Nuclear Technology | Volume 170 | Number 3 | June 2010 | Pages 416-421
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT10-A10327
Articles are hosted by Taylor and Francis Online.
Transuranic (TRU) conversion ratio is a key cost driver of the advanced fuel cycle. The reactor capacity required to consume the national TRU inventory increases as conversion ratio increases. Achieving zero conversion ratio with metal alloy or oxide fuels is fraught with technical challenges. These difficulties can be overcome by hydriding the metal alloy fuel. In this paper, we present the novel concept of using a uranium-free hydrided metal alloy fuel to achieve zero conversion ratio. A reactor core composed of this novel fuel and that would fit in the Sodium Advanced Fast Reactor core geometry was developed; core performance and TRU consumption is estimated and presented. Concerns about the safety of uranium-free fuels are addressed. Although the Doppler effect is nonexistent in a uranium-free fast core, a substantial Doppler effect is present with the uranium-free hydrided metal alloy fuel.