A generic three-dimensional model for solar energy reflected from mirrors in circular orbits

Orbiting solar reflectors may be a useful assets to illuminate solar power farms to enhance their utility when direct sunlight is not available. The assessment of their feasibility for a variety of applications requires accurate calculations of how much solar energy can be delivered from a variety of orbits. This paper presents a generic, three-dimensional semi-analytical model that outputs the quantity of solar energy for a given circular orbit and solar power farm position at the beginning of a pass. The model extends previous studies by including new phenomena such as the Earth's oblateness, rotation, shadow on the reflector and orbit around the Sun, in addition to time-dependent geometric and atmospheric losses. These additions provide new analytical insights into the delivery of reflected solar energy delivery and demonstrate the importance of high-fidelity modelling. The strengths of the model are illustrated for a 1000 km altitude Sun-synchronous orbit throughout, as well as a range of other orbits and solar power farms located at different latitudes and longitudes.