A Sustainable Nuclear Fuel Cycle Based on Laser Inertial Fusion Energy

Abstract

The National Ignition Facility (NIF), a laser-based Inertial Confinement Fusion (ICF) experiment designed to achieve thermonuclear fusion ignition and burn in the laboratory, will soon be completed at the Lawrence Livermore National Laboratory. Experiments designed to accomplish the NIF’s goal will commence in 2010, using laser energies of 1 to 1.3 MJ. Fusion yields of the order of 10 to 35 MJ are expected soon thereafter. We propose that a laser system capable of generating fusion yields of 35 to 75 MJ at 10 to 15 Hz (i.e., ≈ 350- to 1000-MW fusion and ≈ 1.3 to 3.6 x 1020 n/s), coupled to a compact subcritical fission blanket, could be used to generate several GW of thermal power (GWth) while avoiding carbon dioxide emissions, mitigating nuclear proliferation concerns and minimizing the concerns associated with nuclear safety and long-term nuclear waste disposition. This Laser Inertial Fusion Energy (LIFE) based system is a logical extension of the NIF laser and the yields expected from the early ignition experiments on NIF. The LIFE concept is a once-through, self-contained closed fuel cycle and would have the following characteristics: (1) eliminate the need for uranium enrichment; (2) utilize over 90% of the energy content of the nuclear fuel; (3) eliminate the need for spent fuel chemical separation facilities; (4) maintain the fission blanket subcritical at all times (keff <0.90); and (5) minimize future requirements for deep underground geological waste repositories and minimize actinide content in the end-of-life nuclear waste below the (the lowest). Options to burn natural or depleted U, Th, U/Th mixtures, Spent Nuclear Fuel (SNF) without chemical separations of weapons-attractive actinide streams, and excess weapons Pu or highly enriched U (HEU) are possible and under consideration. Because the fission blanket is always subcritical and decay heat removal is possible via passive mechanisms, the technology is inherently safe. Many technical challenges must be met, but a LIFE solution could provide a sustainable path for worldwide growth of nuclear power for electricity production and hydrogen generation.