Conceptual design of laser fusion reactor KOYO-fast - Concepts of reactor system and laser driver

We have carried out the design studies of KOYO-Fast laser fusion power plant, using fast ignition cone targets, diode-pumped solid state lasers, and LiPb liquid wall chambers. Using fast ignition targets, we could design a middle sized 300 MWe reactor module, with 200 MJ fusion pulse energy and 4 Hz rep-rates, and 1200 MWe modular power plants with 4 reactor modules and a 16 Hz laser driver. The liquid wall chambers with free surface cascade flows are proposed for cooling surface quickly enough to a 4 Hz pulse operation. We examined the potential of Yb-YAG ceramic lasers operated at 150 - 225 K for both implosion and heating laser systems required for a 16-Hz repetition and 8 % total efficiency. (authors)