Advanced Solar Energy Flux Analysis for ISRU Operations in Shaded Permanent Craters Near the Edge of the Moon's South Pole

The Moon's Antarctic Permanent Shaded Regions (PSRS) have volatile reserves that are critical for the future use of in-situ resources (ISRUS), but the severe lack of sunlight poses severe constraints on power generation. The study provides a high-resolution solar energy flux analysis that combines LOLA-based topography, minute-scale solar ephemerides, and full-horizon shadow modeling to quantify lighting patterns on the PSR floor and adjacent near-edge areas. The results show that PSRS receive virtually no direct solar radiation during the lunar year, confirming that purely solar power systems are impossible for ISRU operations at the floor level. In contrast, some near-edge mountain ranges have ۶۰ to ۸۰ percent annual brightness and energy densities of ۱۶۰ to ۲۲۰ kWh/m۲ per year, though they are highly dependent on changes in slope and azimuth at the micro scale. These findings highlight the necessity of edge-mounted photovoltaic farms, elevated mast photovoltaic systems, or electric beam architectures to support ISRU'S continuous activities. The flux maps and illumination statistics provided provide a quantitative framework for designing reliable electrical infrastructure in one of the solar system's most constrained environments