Solar Thermoelectric Power Conversion Coupled with Thermal Storage for Orbital Space Applications Presented as Preprint 64-728 at the Third Biennial Aerospace Power Systems Conference, Philadelphia, Pa., September 1-4, 1964. The research reported in this paper was sponsored by the Flight Vehicle Power Branch of the Air Force Propulsion Laboratory and Technology Division under Air Force Contract No. 33(657)-8089 under cognizance of L. D. Massie, Project Engineer for the Air Force

A thermoelectric generator has been combined with thermal energy storage to produce electricity during simulated 90-min orbits with 55 min of sunlight and 35 min of darkness. The experimental model has demonstrated the thermodynamic feasibility of converting solar energy to electric power for space application. The generator produced constant power (± 7%) during simulated orbits in a space chamber and has also operated successfully utilizing natural solar energy. Projection of the feasibility model indicates that a generator with an output of 150 w coupled with a collector-concentrator of 8-ft dia can be built. This system can operate with 0.50 orientation error with a specific power of 2.14 w/lb. Very precise orientation would reduce the area of the collector by 17.5% and increase the specific power, excluding orientation equipment, to 2.3 w/lb. Analysis of the system shows that the thermal storage feature has a significant weight advantage over electrochemical energy storage. This feature also makes the system feasible from an operational standpoint since temperature excursions and warm-up period after solar darkness are eliminated.