Summary of studies on space solar power systems of the National Space Development Agency of Japan

Abstract National Space Development Agency of Japan has examined studies on Space Solar Power Systems (SSPS) since FY1998 organizing a special committee and working group. The FY 1998 studies focused on creating a life cycle cost model of the SSPS which sends energy to the Earth using microwave beams (Microwave Power Transmission; MPT). With the use of this model, technological sensitivity was analyzed to identify key research issues that must be pursued in the future. In addition, a conceptual study was conducted on the SSPS using laser power transmission, with attention paid to fiber array lasers. The FY1999 studies examined a system concept of SSPS, and three types of configurations were proposed. We also proposed a draft of the engineering demonstration satellite while examining major element technology. The FY2000 studies surveyed maturity of major element technologies to exam SSPS system concept. Computer simulation of a direct solar pumping solid-state laser, 5.8 GHz microwave transmitter and receiver system and “sandwich module” integrated PV cell, microwave transmitter and antennas were examined as demonstration of element technology.