A Comparison of Energy Conversion Systems for Meeting the Power Requirements of Manned Rover for Mars Missions

Minimizing system mass for interplanetary missions is of utmost importance in order to keep launch cost within reasonable bounds. For a manned Mars rover, powered by a nuclear reactor power system, the choice of the energy conversion system can play a significant role in lowering the overall system mass. Not only is the mass of the conversion unit affected by the choice, but also the masses of the reactor core, waste heat rejection system, and the radiation shield which are strongly influenced by the system conversion efficiency and operating condition. Several types of conversion systems are of interest for a nuclear reactor Mars Manned application. These conversion systems include: Free Piston Stirling Engines, He/Xe Closed Brayton Cycle (CBC), CO/sub 2/ Open Brayton, and SiGe/GaP Thermoelectric. Optimization studies are conducted to determine the impact of the conversion system on the overall mass of the Nuclear Power system as well as the mobility power requirement of the Rover vehicle.