With the increasingly urgent need to find solutions to the impending energy crisis, there is growing interest within the fusion community in revisiting the concept of the fusion–fission hybrid reactor. But how soon could such reactors be realized, and could they meet the challenges of the coming century?

/pdf/fusion-fission-hybrids-revisited-3v0nrohjlv.pdf

Fusion–fission hybrids revisited

Parameters optimization in a hybrid system with a gas dynamic trap based neutron source

The possibility that a tokamak D-T fusion neutron source, based on ITER physics and technology, could be used to drive sub-critical, fast-spectrum nuclear reactors fueled with the transuranics (TRU) in spent nuclear fuel discharged from conventional nuclear reactors has been investigated at Georgia Tech in a series of studies which are summarized in this paper. It is found that sub-critical operation of such fast transmutation reactors is advantageous in allowing longer fuel residence time, hence greater TRU burnup between fuel reprocessing stages, and in allowing higher TRU loading without compromising safety, relative to what could be achieved in a similar critical transmutation reactor. The required plasma and fusion technology operating parameter range of the fusion neutron source is generally within the anticipated operational range of ITER. The implications of these results for fusion development policy, if they hold up under more extensive and detailed analysis, is that a D-T fusion tokamak neutron source for a sub-critical transmutation reactor, built on the basis of the ITER operating experience, could possibly be a logical next step after ITER on the path to fusion electrical power reactors. At the same time, such an application would allow fusion to contribute to meeting the nation’s energy needs at an earlier stage by helping to close the fission reactor nuclear fuel cycle.

Georgia Tech Studies of Sub-Critical Advanced Burner Reactors with a D-T Fusion Tokamak Neutron Source for the Transmutation of Spent Nuclear Fuel

The straight field line mirror (SFLM) field with magnetic expanders beyond the confinement region is proposed as a compact device for transmutation of nuclear waste and power production. A design w...

/pdf/studies-of-a-straight-field-line-mirror-with-emphasis-on-1vvwm3ydy6.pdf

Studies of a Straight Field Line Mirror with emphasis on fusion-fission hybrids

Slotting a fusion reactor into the heart of a nuclear fission plant could accelerate the development of waste-free nuclear energy. So why are all the designs still on paper, asks Ed Gerstner.

/pdf/nuclear-energy-the-hybrid-returns-51y4se6lxa.pdf

Nuclear energy: The hybrid returns

The design concept of a subcritical advanced burner reactor (SABR) is described. SABR is fueled with transuranics (TRUs) discharged from thermal reactors cast into a TRU-Zr metal fuel pin and is cooled with sodium. The reactor operates subcritical to achieve a deep-burn four-batch fuel cycle that fissions 25% of the TRU in an 8.2-yr residence time, limited by radiation damage accumulation (200 displacements per atom) in the oxygen dispersion strengthened clad and structure. The annual TRU fission rate in SABR [3000 MW(thermal)] is comparable to the annual TRU discharge of three to five 1000-MW(electric) light water reactors, depending on the plant capacity factor of SABR. A tokamak D-T fusion neutron source based on physics and technology that will be demonstrated in ITER supports the subcritical operation.

http://www.frrg.gatech.edu/documents/SABR.pdf

E. Colvin

Papers

A TRU-Zr METAL-FUEL SODIUM-COOLED FAST SUBCRITICAL ADVANCED BURNER REACTOR