A fresh look at space solar power

Studies of systems (circa 1978-1981) to provide solar power from space for terrestrial use defined very large, geostationary Earth orbit (GEO) satellite concepts that-given massive initial government investments and extremely low cost space launch-might have led to power production at costs only somewhat higher than expected commercial prices. These studies of space solar power (SSP) succeeded in establishing technical feasibility. Shortly after the completion of the 1970s study, however, US funding came to an abrupt and seemingly permanent halt-in part because projected costs for the reference system were staggering: well in excess of $100B to achieve the first commercial kilowatt-hour of power. SSP has seen sporadic study and limited experimentation during the past decade (e.g., in Japan). Still, no existing SSP concept has engendered private development. New technologies now make possible concepts and approaches that suggest that SSP economic feasibility may be achievable early in the next century. In 1995, NASA´s Advanced Concepts Office initiated a study taking a fresh look at innovative concepts for SSP that differ markedly from previously examined concepts, addressing innovative system architectures, markets and technologies that could radically reduce initial and operational costs. This paper explores the issues associated with SSP and summarizes the results to date of NASA´s “fresh look” at this important and increasingly timely field of space applications