The Heatpipe Power System (HPS) for Mars outpost and manned Mars missions

Interest continues to increase in using fission reactors to power robotic missions to Mars within the next decade, as well as manned missions in the future. This paper evaluates the use of the Heatpipe Power System (HPS) for these missions (the paper focuses on the reactor core, and does not significantly evaluate power conversion and shielding possibilities). The HPS is a safe, simple reactor that is designed to have a low development time and cost. Previously, most HPS designs have used refractory metals to allow high-temperature operation (for increased power conversion efficiency) and higher thermal conductivity. For use on Mars, a stainless-steer or super-alloy system may be required in order to avoid corrosion. As a result, Los Alamos National Laboratory (LANL) has begun a program to evaluate and test a stainless-steel HPS core. This paper will describe some analysis of potential non-refractory PIPS designs, as well as work that is currently underway to build a full-scale unfueled HPS core. Resistance heated testing will be used to evaluate the thermal performance of the core under a wide variety of conditions; including the simulated Martian atmosphere. Analytical and experimental results thus far indicate that the HPS is very well suited for Martian applications. A near-term, low-cost, low-risk design is proposed for a Mars Outpost application that could provide 40 kWt, and thus 2 kWe with 5% efficient thermoelectrics. A higher power core, 350 kWt, is proposed as a potential surface power source for a manned Mars mission that could provide up to 100 kWe, depending on the efficiency of the power conversion system.