Design optimization of a megawatt scale lunar VSAT solar array farm

The Vertical Solar Array Technology, or VSAT, is a strong candidate to power future missions to the Lunar Poles (Frazier 2022 ). It features an elevated, vertically oriented panel which rotates to always face the Sun. For sites very near the poles, the Sun remains very close to the horizon, which allows a rotating vertical panel to continually receive almost normal-incidence sunlight, therefore maximizing its insolation. However, if multiple VSATs are combined to form a solar array farm, this same feature causes a maximal shade behind each panel, potentially decreasing the insolation of the other ones. This paper presents a novel approach to optimize such a farm taking account of self-shading and minimizing blackout and brownout periods. This approach, which requires many insolation computations, is made feasible by using a ’sky bitmask’ method common on Earth but not applied (to the authors’ knowledge) on the Moon. It applies the approach to propose a design for a megawatt scale facility near the lunar south pole.