Some licensing and regulatory-related work has been done for the ITER program, and much of that work provides insights into IFE licensing processes and issues. The LIFE program has considered licensing issues more than any other IFE program; however, much more effort would be needed if IFE were to seriously pursue an NRC license. The Next Generation Nuclear Plant (NGNP) fission reactor project plans to license and build a high-temperature gas fission reactor. Gas reactors have been built and operated previously in the United States and Europe, although at lower operating temperatures than are envisioned for the NGNP. The licensing strategy developed for the NGNP provides a good picture of the challenges associated with licensing a relatively standard technology.65
The licensing of fission power plants is moving toward a risk-informed approach, whereas in the past it took primarily a deterministic approach. The LIFE program is developing a similar approach.66 The favorable safety characteristics of the IFE and MFE fusion plants should simplify the licensing process; however, the burden of proof for IFE plants will be no different than for fission plants. One of the safety-related goals for fusion is to demonstrate that there would never be a need for public evacuation under any event. This is a clear example of the favorable safety characteristics of a fusion plant.
Conclusion 3-20: Some licensing/regulatory-related research has been carried out for the ITER (magnetic fusion energy) program, and much of that work provides insights into the licensing process and issues for inertial fusion energy. The laser inertial fusion energy (LIFE) program at Lawrence Livermore National Laboratory has considered licensing issues more than any other IFE approach; however, much more effort would be required when a Nuclear Regulatory Commission license is pursued for inertial fusion energy.
Safety analysis has been an important part of the IFE design studies cited earlier. Early analyses were relatively simple. They often looked at total inventories of radioactive material and determining how much material could be released based on total system energy. These analyses have given way to more sophisticated analyses, sometimes employing tools originally developed for the fission industry and adapted to fusion.67 Tritium inventory and release mitigation is an important part of the fusion safety case. Tritium can be highly mobile under certain condi-
66 M. Dunne, E.I. Moses, P. Amendt, et al., 2011, Timely delivery of laser inertial fusion energy (LIFE), Fusion Science and Technology 60: 19-27.
67 B.J. Merrill, A lithium-air reaction model for the MELCOR code for analyzing lithium fires in fusion reactors, Fusion Engineering and Design 54: 485-493.