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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.
Huseyin Atilla Ozgener
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 281-286
Modeling and Simulations | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13433
Articles are hosted by Taylor and Francis Online.
The criticality eigenvalue problems of both multigroup diffusion and transport theories have slow rates of convergence when the dominance ratio is close to one. This situation arises especially in the analysis of loosely coupled reactor systems and necessitates the use of acceleration techniques. The coarse mesh rebalance method constitutes one of the prominent ones of such acceleration schemes. The coarse mesh rebalance method has been used in the acceleration of direct diffusion criticality eigenvalue problems. In this study, this acceleration method is utilized also in the solution of adjoint diffusion problems in spherical geometry. The efficiency of the acceleration method is assessed through numerical experiments and certain conclusions have been drawn regarding the use of coarse mesh rebalance in such problems.
