Abstract: A key subsystem for space flight and planned bases of space exploration is electrical power generation. It requires high reliability and long duration of performances. Thermoelectric conversion system has been successfully employed for this purpose in a number of missions of NASA's space programmes.In this paper,thermoelectric generators using radioiso- tope and nuclear reactor as heat sources were described and the applica- tions were listed.

Key words: Energy conversion, Thermoelectric generator, Semiconductor function device, Space power system