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Thomas H. Fanning

Senior Advisor to the Assistant Secretary for Nuclear Energy


Dr. Fanning is currently serving as Senior Advisor to DOE’s Assistant Secretary for Nuclear Energy. Previously he served as Director of Nuclear Design for DOE’s Versatile Test Reactor Project and was manager of the Safety and Engineering Analysis Department in the Nuclear Science and Engineering Division, where he oversaw methods development and applications for a wide range of advanced reactor systems analysis activities. He received his Ph.D. in Nuclear Engineering and Engineering Physics from the University of Wisconsin and has worked at Argonne National Laboratory since 1994. He has made significant contributions in the areas of core design, fuel cycle analysis, waste form development, repository modeling, advanced systems modeling, and reactor safety. Dr. Fanning is the code manager for the SAS4A/SASSYS-1 safety analysis system and has extensive expertise in fast reactor design and safety. He was a member of the American Nuclear Society Special Committee on SMR Generic Licensing Issues and was nominated for the National Academy of Engineering’s 2010 Frontiers of Engineering. From 2014 to 2017 Dr. Fanning served as the U.S. representative to the Generation IV International Forum Sodium Fast Reactor Safety and Operations Project Management Board. Currently he serves as the U.S. representative to the Generation IV Expert Group.