NASA Game Changing Development program backed Kilopower, with the goal of building and testing a small fission reactor by Sept. 30, 2017, the end of the current fiscal year. The project is costing about $15 million.

The test reactor, which is about 6.5 feet tall (1.9 meters), is designed to produce up to 1 kilowatt of electric power, but to keep costs down, the test unit does not include a full array of Stirling engines to convert energy generated by the fission process into heat. Thermal simulators will be used for the balance of the engines to verify the reactor's power output

NASA recently completed a feasibility study for small fission power systems (FPS). As NASA is seeking game changing technologies to transform the nation's space mission capabilities, small FPS could reduce NASA's dependence on plutonium. A small kilowatt-class FPS could enable future flagship science missions and exploration precursor missions that may not otherwise be possible.