A TECHNICAL OVERVIEW OF THE “SUNTOWER” SOLAR POWER SATELLITE CONCEPT

Abstract

During 1995–1996, the National Aeronautics and Space Administration (NASA) conducted a far-reaching reexamination of the technologies, systems concepts and terrestrial markets that might be involved in future space solar power (SSP) systems. The principal objective of this “fresh look” study was to determine whether a solar power satellite (SPS) and associated systems could be defined that could deliver energy into terrestrial electrical power grids at prices equal to or below ground alternatives in a variety of markets, do so without major environmental drawbacks, and which could be developed at a fraction of the initial investment projected for the SPS Reference System of the late 1970s. One of the key concepts emerging from the “fresh look” SSP study is the “SunTower” SPS system. This concept exploits a variety of innovative technologies and design approaches to achieve a potential breakthrough in establishing the technical and programmatic feasibility on initial commercial SSP operations. Capable of being deployed to either low Earth orbit or middle Earth orbit altitudes and various inclinations, the SunTower concept involves essentially no in-space infrastructure and requires no unique heavy lift launch vehicle. The concept, which can provide power to global market places appears to allow up to a factor of 30:1 reduction in initial investment requirements, compared to the 1979 SPS Reference Concept. This paper presents a technical overview of the SunTower SPS concept, including key technologies, sensitivity trades, operational scenarios. Potential non-SPS space program uses of the SunTower concept and related technologies are identified, including human exploration, space science and commercial space applications.