Implications of inter-satellite power beaming using a Space Power Grid

This paper considers the conditions, opportunities and constraints under which beamed power might be attractive for space-based enterprises. First, an evolutionary, revenue-generating architecture for beaming electric power through space to terrestrial and space-based customers is presented, to understand the likely environment where full-scale Space Solar Power will become a reality. The Space Power Grid approach trades the large risks inherent in the launch cost reductions required for GEO-based microwave SSP concepts, against the nearer-term prospects of advances in millimeter wave and infrared laser conversion, beaming and reception. Space is envisioned as a venue for real-time power exchange between terrestrial power plants. With a constellation of 100 millimeter wave relay spacecraft in 2000km sun synchronous orbits trading with 200 ground stations, the system is shown to break even inside 17 years with fairly realistic parameters, facilitating a revenue-generating scale-up to full SSP. Conditions needed to break even by 50 years from project inception at a level of 3.4 Terawatts are presented. The logic of beaming to space-based customers is explored, concluding that this becomes viable mostly where high power levels are needed, implying either power-intensive commercial enterprises in orbit, or beamed propulsion.