Preliminary development of a milliwatt generator for space

This paper presents the results of a Phase I STTR program to develop a small thermoelectric generator for use in space. The generator is designed to use the existing 1 watt radioisotope heater unit (RHU) which is currently used to keep instruments warm in space. The design and manufacture of the monolithic thermal conversion unit (TCU) is discussed as is a conceptual design of a generator which uses both the RHU and the small TCU to produce 40 mW of power at 5 volts DC.