LIFE commercialization begins with subsystem development and laboratory-based technology demonstrations, and then moves directly to a plant capable of continuous fusion operations. The plant is highly flexible and can be configured to support subscale qualification testing as well as commercial power production. This strategy is enabled by the modular architecture of the design and the fact that the fusion chamber and major laser system components are line-replaceable units.
This approach has significant advantages. It avoids the need for an intermediate-step engineering test facility, which is a multi-billion-dollar capital investment. Gaining the approval and funding for a test facility, as well as for the first commercial plant, adds significant programmatic risk. Further, the technology requirements for an engineering test facility are substantially the same as for the first plant. Both require high-average-power operation of the laser, hitting and igniting targets on-the-fly, tritium self-sufficiency, and so on. For LIFE, there is little advantage to an intermediate-step facility.
Perhaps even more importantly, the flexible configuration of the first plant mitigates the risk of technology development concurrent with plant design and construction. For example, testing in NIF may result in a change of the laser energy requirement for the first plant. The modular architecture accommodates this by allowing one to add or subtract beam lines from the laser system, with minimal impact to the overall plant design. Similar flexibility applies to the fusion chamber. One can transition directly to full-scale hardware and power production; however, if warranted, subscale hardware can be qualification tested at reduced fusion power levels prior to full scale testing. The ability to develop technology concurrent with first plant design, without the risk of “building the wrong plant,” significantly reduces time to market and enhances the relevance of fusion energy.
Many of the components needed for a fusion power plant can be developed and tested in a laboratory setting. Examples include high-average-power lasers, tritium handling systems, and corrosion-resistant materials. However, once ignition has been demonstrated, the critical path to commercial fusion energy is dominated by the need to have a quasi-continuous fusion source to qualify materials and processes needed in a commercial plant. Examples of materials and processes that will need this qualification include on-the-fly fusion target ignition with repeatable fusion yield and final optic survival in fusion environment.
Materials and structures need to be exposed to the same thermal and radiation loads as will be experienced in a commercial power plant. In addition, the exposure time must be long enough to simulate one or more system lifetimes, for systems such as the fusion chamber and final optic. This can be done in a full-scale fusion chamber, operating at full commercial plant fusion power level, or in a subscale fusion chamber operating at lower average power. This flexibility to test at multiple scales provides significant risk mitigation and allows initial materials qualification testing at small scale, should regulatory or technical issues mandate.
Once the materials and process qualification is complete, the plant will transition to regular operations, delivering 400 MW of commercial power to the grid.
T.M. Anklam et al., “LIFE: The Case for Early Commercialization of Fusion Energy,” Fus. Sci. Tech. 60, 66–71 (2011).
M. Dunne et al., “Timely Delivery of Laser Inertial Fusion Energy (LIFE),” Fus. Sci. Tech. 60, 19–27 (2011).