Radioisotope thermophotovoltaic power system utilizing the GaSb IR photovoltaic cell

Unique challenges to space power systems engineers are posed by the special requirements of lunar and planetary surface missions as well as deep space missions where solar photovoltaic conversion is not a viable option. An approach to these problems is the utilization of radioisotope decay to generate infrared (IR) power (heat) which is converted to useable electric power via the application of IR photovoltaic (PV) technology. This paper presents the progress status of an innovative concept for such a radioisotope thermophotovoltaic (RTPV) power system. Results for IR photovoltaic cell development indicate near theoretical PV performance can be obtained and computer simulation of these cells operating within an RTPV system yield an overall system efficiency of ∼13%. Neutron testing of the TPV cells have demonstrated an approximate 20% power reduction at the end of a 10 year mission lifetime. In addition, the results of a proprietary modification of the isotope heat source will be shown which is predicted ...