A Solar Power Satellite Sending an Infrared Beam from GEO to 40 Efficient Concentrating Solar Power Modules on the Ground 24 Hours per Day

摘要

Harvesting solar energy in space from a GEO orbit and RF beaming it down to earth has been a dream since the oil crisis in the 1970's. However, the colossal and expensive first step required to achieve this goal has stifled its initiation. The problem derives from the dispersion of the beam associated with the long RF wavelength leading to a multi-km size receiver station and a km-size satellite and a costly multibillion dollar development project for a GW sized satellite. Using a shorter wavelength infra red beam reduces the dispersion and ground station size and consequently the satellite size from GWs to MWs or less. Herein, a satellite with a diode pumped Er:YAG laser generating an IR beam is proposed. The 40 m diameter ground station can receive eye-safe IR radiation. Modular concentrating IR arrays with GaSb IR photovoltaic cells can then generate electricity 24 hours per day with an efficiency of 40%. The economics for this concept are described and promising for national security niche power markets.