NSE - Nuclear Science & Engineering at MIT


Uranium startup fast reactors

Nuclear fuel reprocessing and recycle are unlikely to be deployed in the US in the foreseeable future, due in large part to unfavorable economic prospects. However, fast breeder reactors remain our principal assurance of long-term sustainability of nuclear energy. A CANES group has developed a generic fast reactor core design, using a once-through fuel cycle, applicable to a wide variety of fast reactor fuel and coolant types, which matches the uranium utilization and fuel cycle cost of LWRs. The principal enabling feature is the replacement of conventional uranium blankets by high-albedo reflectors of materials such as MgO and Zr. It was also shown that the used fuel could eventually be removed from storage and employed as the feed for recycle-mode breeding, if and when need be. Accordingly, near-term fast reactor deployment can now be pursued to focus on capital cost reduction without negatively impacting the uranium market.


  1. T. Fei, E. Shwageraus, M.J. Driscoll, “A Cost-Effective Once-Through Startup Mode for SFRs,” Trans. Am. Nucl. Soc., Vol. 104, Hollywood, FL, 2011
  2. J. Richard, “A Strategy for Transition from a Uranium Fueled, Open Cycle SFR to a Transuranic Fueled, Closed Cycle SFR,” SM Thesis, MIT Dept. of Nuclear Science and Eng., May 2012
  3. R.R. Macdonald, M.J. Driscoll, “Magnesium Oxide: An Improved Reflector for Blanket-Free Fast Reactors,” Trans. Am. Nucl. Soc., Vol. 102, June 2010

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