Research Overview Transmutation Reactors

Transmutation Reactors

Closing the nuclear fuel cycle requires 1) extracting the transuranics in spent nuclear fuel and using them as fuel in transmutation reactors, thereby reducing by orders of magnitude the long-lived transuranics that must be buried in waste repositories that must be secured for tens to hundreds of thousands of years, and 2) transmuting a large fraction of the > 99% of uranium that is U238 into plutonium and subsequently fissioning it to extract a large fraction of the energy content of uranium.  There appear to be some advantages to operating these transmutation reactors sub-critical with a neutron source.

The concept of a fast transmutation reactor driven by a tokamak D-T fusion neutron source that could be built on the basis of ITER physics and technology and ITER operating experience has been under development in a series of faculty-student conceptual design studies and student theses at Georgia Tech for the past several years.


W. M. Stacey. “Solving the Spent Nuclear Fuel Problem by Fissioning Transuranics in Subcritical Advanced Burner Reactors Driven by Tokamak Fusion Neutron Sources.” Preprint of paper submitted to Nuclear Technology, 2017


W. M. Stacey, A. T. Bopp, J-P. Floyd, M. D. Hill, A. P. Moore, B. Petrovic, C. M. Sommer, C. L. Stewart and T. M. Wilks, The SABR TRU-Zr Fuel, Modular Sodium-Pool Transmutation Reactor Concept. Nuclear & Radiological Engineering Program Seminar, Georgia Institute of Technology, September 22, 2016


Stacey, Weston M. “A strategic opportunity for magnetic fusion energy development.” Journal of Fusion Energy 35.1 (2016): 111-116.


W. M. Stacey, C. L. Stewart, J.-P. Floyd, T.M. Wilks, A.P. Moore, A.T. Bopp, M.D. Hill, S. Tandon, and A.s. Erickson. “Resolution of Fission and Fusion Technology Integration Issues: An Upgraded Design Concept for the Subcritical Advanced Burner Reactor.” Nucl. Technol. Vol. 187, 15, June 2014,

C. L. Stewart and W.M. Stacey. “The SABrR Concept for a Fission-Fusion Hybrid 238U-to-239Pu Fissile Production Reactor.” Nucl. Technol. Vol. 187,1, July 2014.


C. M. Sommer, W. M. Stacey, B. Petrovic, and C. L. Stewart. “Transmutation Fuel Cycle Analyses of the SABR Fission-Fusion Hybrid Burner Reactor for Transuranic and Minor Actinide Fuels”. Nucl. Technol. Vol. 182, 274, June 2013.


W. M. Stacey, C. M. Sommer, B. Petrovic & the Georgia Tech SABR Design Team., “Georgia Tech SABR Studies of a Fusion-Fission Hybrid Fast Burner Reactor”, Karlsruhe Institute of Technology, Karlsruhe, Germany, February 1, 2011.

W. M. Stacey. “Tutorial: Principles and Rationale of the Fusion-Fission Hybrid Burner Reactor”. FUNFI – 2011 Workshop: Fusion for Neutrons and Sub-Critical Fission Systems. Varenna, Italy. 13 September 2011.


T. S. Sumner, W. M. Stacey, and S. M. Ghiaasiaan, “Dynamic Safety Analysis of the SABR Subcritical Transmutation Reactor Concept”, Nucl. Technol. Vol. 171, 123, August 2010.

C. M. Sommer, W. M. Stacey, and B. Petrovic, “Fuel cycle Analysis of the SABR Subcritical Transmutation Reactor Concept”, Nucl. Technol. Vol. 172, 48, October 2010.

W. M. Stacey, C. M. Sommer, T. S. Sumner, B. Petrovic, S. M. Ghiaasiaan, C. L. Stewart, “SABR Fusion-Fission Hybrid Fast Burner Reactor Based on ITER”, 11th OECD/NEA Information Exchange Meeting on Actinide and Fission Product partitioning and Transmutation, San Francisco, 1-5 November 2010.

V. Romanelli, C. Sommer, M. Salvatores, W. Stacey, W. Maschek, B. Petrovic, et al., “Advanced Fuel Cycle Scenario Study on the European Context By Using Different Burner Reactor Concepts”, 11th OECD/NEA Information Exchange Meeting on Actinide and Fission Product partitioning and Transmutation, San Francisco, 1-5 November 2010.


W. M. Stacey, “Georgia Tech Studies of Sub- Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel”, J. Fusion Energy 28, 328 (2009).

W. M. Stacey, “A Tokamak Neutron Source for Hybrids”, Georgia Institute of Technology, October 16, 2009.


W. M. Stacey, et al., “A TRU-Zr Metal Fuel, Sodium Cooled, Fast Subcritical Advanced Burner Reactor”, Nucl. Technol. 162, 53 (2008).


W. M. Stacey, et al., “Advances in the Sub-Critical, Gas-Cooled, Fast Transmutation Reactor Concept”, Nucl. Technol. 159, 72 (2007).

W. M. Stacey, “Transmutation Missions for Tokamak Fusion Neutron Sources”, Fusion Engr. Des. 82, 11 (2007).

W. M. Stacey, “Sub -Critical Transmutation Reactor with Tokamak Fusion Neutron Sources Based on ITER Physics and Technology”, TOFE-17 paper, Fusion Sci. & Technol. 52, 719 (2007).

J-P. Floyd, et al., “Tokamak Neutron Source for a Fast Transmutation Reactor”, Fusion Sci. & Technol. 52, 727 (2007).

W. M. Stacey, “SABR Subcritical Advanced Burner Reactor”, Georgia Tech., (2007).


W. M. Stacey, “Capabilities of a DT Tokamak Fusion Neutron Source for Driving a Spent Nuclear Fuel Transmutation Reactor”, Nucl. Fusion 41, 135 (2001).