Thermal Energy Storage and Power Generation for the Manned Outpost using Processed Lunar Regolith as Thermal Mass Materials

[Abstract] This paper presents the results of an evaluation of the use of thermal energy reservoirs, using processed lunar regolith as the thermal mass, for electrical power generation during periods of darkness at a human-occupied outpost on the Moon. The reference conceptual approach utilizes propellant tanks from the Altair Lunar Lander plus thermal mass materials produced as by-products of oxygen production from an In Situ Resource Utilization (ISRU) plant. Propellant tanks would be loaded with spheroidically shaped thermal bricks from the ISRU plant 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 operation of Stirling cycle heat engines, intermediate heat sinks and radiators. We calculate that the storage volume obtained from the tankage of one Altair Descent Stage can support net power generation at an average rate of 8.0 kWe during the longest period of darkness currently anticipated at Site A of Shackleton Crater, a site in discu ssion as a possible location for a manned lunar outpost. The power density, based upon the additional mass that must be transported to the Moon for this configuration, is estimated to be between 8 and 11 W e/kg.