SPS Built of Lunar Materials. Space Studies Institute RFP 1984

2 a microwave beam of low power density (25 mW/cm ), precisely to one or more receiving antennas at desired locations on Earth. At the receiving antenna, the microwave energy would be safely, efficiently reconverted into electricity and transmitted to users. An SPS system would consist of many SPS1s in GEO, with outputs at the receiving antennas designed to meet power demands. NASA, in support of SPS evaluations performed by the U.S. Department of Energy, evolved an SPS reference system which assumed that 5 gW of base load output electric power would be generated at the receiving antenna. The reference system was intended as a tool for inquiry, rather than as the design for an SPS which would actually be constructed and commercialized in the 21st century. It was assumed in the reference design that all components of the SPS were to be lifted from the Earth. The Office of Technology Assessment (OTA) carried out an independent review of the SPS concept, which was published in August, 1982 (reference #1). This review was not restricted to the NASA SPS reference design, but covered a broad range of possible SPS concepts as well as many policy issues. The review concluded that SPS is a viable alternative energy system, but that decisions to proceed with further funding depend on the future availability of other energy sources, which could not be adequately assessed at the time of the report. The OTA suggested to Congress that if it decided not to start a dedicated SPS research effort, it might dedicate an agency to track generic research applicable to SPS, to review trends and electricity demand, and to monitor the progress of other electrical supply technologies. Such a mechanism would provide the basis for periodic assessment of whether to begin an SPS research program. Another