Space Power Generation - The proposed innovation has the potential to support space power generation applications in the 75-500 W electrical power range using thermal input from one or more radioisotope heat sources, with waste heat radiated to space. Overall conversion efficiency is projected to be around 31% with a 640C heat source and 60C radiator. Other heat source/sink options and temperatures are possible depending on convertor efficiency requirements. Cooling - The convertor is a reversible heat engine and can be run backwards to produce cooling in the cryogenic temperature range (50-100 K) from electrical input. By introducing staging lower temperatures are possible. NASA cooling applications include direct cooling of space sensors, vapor re-liquefaction for zero-boiloff fluid storage or cooling superconducting magnetic bearings in support of flywheel energy storage systems.
Our convertor has the potential to be a lower-cost alternative to other Stirling machines and might find application as a generator using natural gas or renewable biofuels. The redundant convertor configurations could be beneficial for terrestrial remote power applications requiring high reliability (e.g. navigation or communications equipment in off-grid areas). Operated as a cryocooler, the convertor could cool high-temperature superconducting magnetic bearings in industrial spindles and motors. The ability to cool a central load and reject heat at the periphery is ideal for zero-boiloff re-condensation of liquid nitrogen, volatile fuels and other substances. The core hydrodynamic bearing technology could be applied to linear free-piston compressors for domestic refrigeration. The Department of Energy Office recently issued a new Roadmap report which prioritized accelerating the commercialization of high-efficiency appliance technologies. This Roadmap ranked the development of advanced compressor technologies for refrigerators and freezers as having the highest overall importance and potential impact.