A Fission Surface Power Unit with Free-Piston Stirling Conversion Sized from Its Waste-Heat Budget

This study sizes a fission surface power unit delivering 40.0 kilowatts of electricity through free-piston Stirling conversion at an efficiency of 0.25, requiring 160 kilowatts of reactor thermal power and rejecting 120 kilowatts of waste heat through a radiator at 400 kelvin with an area of 91.9 square metres. Uranium-235 consumption is 0.06 kilograms per year, or 0.6 kilograms over a ten-year operating life. Sizing follows from computed energy and thermal budgets derived in the study. This is a computed study with no targeting or weapon application. The work is simulated and computed from stated assumptions, not measured.