Solar Concentrator Concept for Providing Direct Solar Energy for Oxygen Production at the Lunar South Pole

Abstract

A hydrogen reduction reactor (ROxygen) is currently under test and development by the Johnson Space Center. It utilizes an electric heater as the heat source. Solar energy is readily available and abundant on the lunar surface. It is more efficient to use it directly as the energy source for heating the soil in the reactor rather than first converting it to electrical energy to power an electric heater. Solar photovoltaic (PV) or thermo -dynamic systems for converting the solar energy into electrical energy will still be required for the process but to a lesser extent if direct solar heating is utilized. A concept is defined that utilizes an offset parabolic concentrator to collect and focus solar energy directly into the ROxygen reactor. The concept is based on a production site at the lunar South Pole where the sun orbits the site on a 29.5 day cycle. The sun is constantly at the horizon and changes vertical position from the horizon only slightly. The offset parabolic concentrator is rotated to track the sun. It is attached to and positioned above t he reactor and rotates independently via a special bearing support and structure. The parabolic surface is designed to capture the solar energy and direct it vertically downward into the ROxygen reactor. The reactor and associated support equipment are f ixed in position on the lunar surface. A two axis solar tracking system and a concentrator positioning system are utilized to keep the concentrator perfectly aligned with the sun and the focal point centered at the reactor aperture. This report presents the work accomplished to date in defining the overall concept including: