The TELEC - A plasma type of direct energy converter

Long distance transmission of power in space using a laser beam is an attractive concept because of the very narrow beam divergence. Such a system requires efficient means to both generate the laser beam and to convert the light energy in the beam into useful electric power at the receiver. A plasmatype device known as a Thermo-Electronic Laser Energy Converter (TELEC) has been studied as a method of converting a 10.6y CO^ laser beam into electric power. In the TELEC process, electromagnetic radiation is absorbed directly in the plasma electrons producing a high electron temperature. The energetic electrons diffuse out of the plasma striking two electrodes with different areas. Since more electrons are collected by the larger electrode, there is a net transport of current, and an EMF is generated in the external circuit. Theoretical calculations indicate potential TELEC efficiencies in the range of 40% 50%. An experimental TELEC apparatus was constructed and tested at the Ames Research Center using a 40 kW combustion laser. Cesium vapor plasmas were formed in the TELEC apparatus and electrical power outputs were observed.