SOMBRERO-a solid breeder moving bed KrF laser driven IFE power reactor

SOMBRERO, a conceptual design study of a 1000-MWe KrF laser driven IFE (inertial fusion energy) power reactor utilizing direct drive targets with near symmetric illumination, is described. The chamber is constructed of a low-activation carbon/carbon composite and the blanket consists of a moving bed of solid Li₂O particles flowing through the chamber by gravity. The particles are transported through the intermediate heat exchanger and around the loop in a fluidized state by He gas at 0.2 MPa. There are 60 laser beams in near-symmetric distribution; the laser energy is 3.4 MJ; the target gain is 118; and the rep-rate is 6.7 Hz. The chamber has a cylindrical central region with conical ends, a minimum radius of 6.5 m, and a blanket/reflector thickness of 1 m at the midplane giving a tritium breeding ratio of 1.25 and an overall energy multiplication of 1.08. A grazing incidence metallic mirror is located 30 m from the target, and the final focusing dielectric coated mirror which is shielded from direct neutrons is located at 50 m. The inlet temperature of the Li₂O particles is 550°C, the equilibrated outlet temperature is 740°C; and the power cycle efficiency is 47%. Using a laser efficiency of 7%, the driver power is 325 MWe. The gross power output is 1360 MWe, giving a net power output of 1000 MWe, with 360 MWe used for the driver and auxiliary equipment