System Concepts to Reduce Logistics Requirements for Space Exploration

Abstract

Because of the high cost to transport mass to the Moon, Mars, or a Near Earth Object (NEO), the logistics of space exploration are a major cost driver that can make or break a sustainable exploration program, whether that program be based on human exploration, robotic exploration, or some combination of the two. For a comprehensive campaign of space exploration to be successful and sustainable, new logistics methodologies and systems to support them must be developed. Battelle has developed conceptual designs that can greatly reduce the logistics requirements for long-term campaigns of space exploration. This paper describes two of these concepts and how they can be used to achieve reductions in space logistics requirements. The two concepts presented are: 1) thermal energy reservoirs that utilize processed lunar regolith to produce heat and electrical power; and 2) an ultra-efficient human exploration architecture that couples closed loop life support with the production of food and/or fuels that can be utilized for propulsion and power generation. While these two concepts are very different, they share a common philosophy of using inputs (gasses, materials, etc.) that would be considered by many to be unusable waste products. In any space exploration endeavor, where the cost of forward deploying basic resources such as air, water, food, and fuel is extremely high, resources must be conserved to the maximum extent possible to keep the costs of the exploration campaign from becoming prohibitively expensive. To accomplish this, the elements of the system of systems that will comprise the exploration infrastructure must be designed to complement each other so that one system’s byproducts are the feedstock for other systems. The first conceptual design utilizes materials produced as waste byproducts of oxygen production from a lunar In Situ Resource Utilization (ISRU) system to be configured as thermal reservoirs for the storage and dumping of heat. The concept also uses a spent lunar lander, after it has completed its primary mission of delivering payloads to the lunar surface, to function as a power generation station. In this concept, the waste material from the ISRU process would be loaded into the lunar lander’s propellant tanks and configured to function as heat sources and intermediate heat sinks. During periods of sunlight, solar energy would be concentrated and stored as thermal energy in high temperature, thermal energy reservoirs and then used for power generation during periods of darkness through the use of Stirling cycle heat engines, intermediate heat sinks, and radiators. In the reference design, where both the heat sources and the intermediate heat sinks make use of the propellant tanks, a net power generation of 8.0 kWe was calculated to be available – using the tankage of one baselined Altair Lunar Lander – throughout