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.
Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
Standards Program
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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
Latest News
Nuclear fuel cycle reimagined: Powering the next frontiers from nuclear waste
In the fall of 2023, a small Zeno Power team accomplished a major feat: they demonstrated the first strontium-90 heat source in decades—and the first-ever by a commercial company.
Zeno Power worked with Pacific Northwest National Laboratory to fabricate and validate this Z1 heat source design at the lab’s Radiochemical Processing Laboratory. The Z1 demonstration heralded renewed interest in developing radioisotope power system (RPS) technology. In early 2025, the heat source was disassembled, and the Sr-90 was returned to the U.S. Department of Energy for continued use.
Kenton Sherick, Aniruddha Ray, Pierre Berneron, B. Allen Tolson, Chadwick Barklay, Maarten den Heijer, Christofer E. Whiting
Nuclear Technology | Volume 211 | Number 1 | April 2025 | Pages S38-S48
Research Article | doi.org/10.1080/00295450.2024.2369825
Articles are hosted by Taylor and Francis Online.
Over the past 25 years, the average cadence of National Aeronautics and Space Administration (NASA) missions that employ radioisotope thermoelectric generators (RTGs) or other radioisotope power systems (RPSs) is approximately one per decade. Currently, the only flight-qualified RPS in the NASA inventory for space power applications is the multi-mission RTG, which has a beginning-of-life (BOL) power output of approximately 120 W(electric). In addition, NASA and the U.S. Department of Energy also manage the Next Generation Radioisotope Thermoelectric Generator Development Project, with a projected BOL power of around 245 W(electric).
However, if a lower-power RPS unit was available, would there be sufficient mission pull to increase the cadence of RPS-powered missions? We believe the answer to this question is yes, which drove the evolution of a concept study that examines the feasibility of a low-power RPS based on a single general purpose heat source (GPHS) that could be developed rapidly with low risk and cost. This paper discusses the results of a concept study of an RPS system that utilizes novel ruggedized silicon germanium thermoelectric modules with a projected BOL power of 15 W(electric).
This new RTG design could help enable a new class of low-powered space exploration missions for NASA, the European Space Agency, or commercial applications. In addition, this paper addresses the next steps required to evolve the concept beyond its current status to conceptual design.
