Evolution of Light Ion Driven Fusion Power Plants Leading to the LIBRA-SP Design

The use of light ion or electron beams to compress matter to the densities required for fusion has been proposed for more than 20 years. In the past ten years, a series of light ion beam power plant conceptual designs have been published under the generic name LIBRA. Considerable advances in both physics and technology have allowed major improvements from the design performance of the earliest LIBRA 330 MW_e power plant to the more recent 979 MW_e LIBRA-LiTE, and the 1000 MW_e LIBRA-SP reactors. The recent declassification of target designs allows more realistic target spectra, gains, and injection parameters to be analyzed. The pulsed power driver technology has matured to the point that Helia induction technology can be tested in the laboratory under single pulse conditions and confidently extrapolated to LIBRA repetition rates. New concepts for protecting the first structural wall of the reactor have been developed; the use of flexible INPORT (INhibited Flow in PORous Tube) and rigid PERIT (PErforated RIgid Tube) units allow the reflector and first wall to last the lifetime of the power plant. The use of PbLi eutectic alloy has greatly improved the safety features of these reactors and the economics of all three compare very favorably to the tokamak, laser, and heavy ion beam reactors.