NASA has been harnessing the power of radioisotope systems for years to explore the vastness of space. These nuclear power sources generate electricity by transforming the heat from radioactive decay into usable energy, primarily using plutonium-238. However, there’s been a longstanding interest in exploring americium-241 as an alternative. Now, in partnership with the University of Leicester, NASA is putting this interest to the test.
The focus is on a free-piston Stirling convertor, which efficiently converts radioisotope heat into electricity. Unlike conventional engines with crankshafts, this convertor employs free-floating pistons, reducing wear and enhancing longevity by forgoing traditional piston rings and rotating bearings. This innovation promises more energy output over extended periods, ideal for intense deep space missions.
The collaboration saw the University of Leicester providing heat source simulators and generator housing, while NASA Glenn’s Stirling Research Lab contributed the test station, convertor hardware, and support equipment. The test setup used two electronically heated americium-241 simulators, matching the size of the actual heat sources.
The results were promising. A notable feature demonstrated was the testbed’s capacity to maintain electrical power even if a Stirling convertor failed. This success indicates a promising future for the Americium-Radioisotope Stirling generator, paving the way for sustainable energy in prolonged space missions.
