New commercial and military applications for space power are developing over a wide range of nominal and peaking power requirements. Power levels far exceed the capabilities of photovoltaic array and battery systems. Factors such as manned and unmanned missions, long mission durations, zero-maintenance requirements, hardening from attack, and mission orbit or mission payload impact space power system specifications and dictate the type of energy source. This has led to emphasis on the closed Brayton cycle (CBC) with its inherent flexibility as a dynamic power source.
Unique features of the CBC contribute to its application to the multiplicity of space power requirements. These include flexibility of design, operation, energy source selection, and future growth.
The CBC with the single-phase, gas working fluid provides a simple interface for chemical, isotope, solar, and nuclear thermal energy sources. The single-phase gas is not affected by zero gravity, freezing or high temperatures, vehicle launch, or flight maneuver loads. This feature is a primary contributor to the CBC flexibility.