Americium-241-powered space radioisotope thermoelectric generator

Since there is a shortage of the plutonium-238 radionuclide, which had been used in radioisotope thermoelectric generators (RTG) as a source of electric power for deep-space spacecraft, the paper discusses and demonstrates the feasibility of developing and RTG, which will use as its primary source of power the americium-241 radionuclide with half-life period of 432 years. The paper provides general information about americium-241 and current status of work on the application of americium-241 to RTG. The paper describes americium-241 -based RTG designs for 1...5 and 5...50 W electrical power and prototypes of micro-modular low-temperature and two-stage medium-temperature thermoelectric battery. A comparison of parameters of RTGs based on americium-241 and plutonium-238 in the 1.30 W electrical power range showed that RTGs with electrical power above 10 W, both based on americium-241 and plutonium-238, have similar levels of efficiency estimated at about 7%. The paper discusses the existing options and obstacles that need to be overcome in order to develop americium-241 RTGs for space applications using existing and future thermoelectric materials.