Na razie Plutonu 238 nie brakuje, ale produkcja powinna być uzależniona od dalekosiężnych planów jego wykorzystania.
Można też użyć wydajniejszych metod produkcji.
Plutonium supply for NASA missions faces long-term challengesby Jeff Foust — October 10, 2017
(...) Several factors beyond the needs for planetary missions could affect the available supply of plutonium-238. One is the development of more efficient alternatives to conventional RTGs, known as dynamic converters, that could generate the same amount of power using less of the isotope. One concept, the Advanced Stirling Radioisotope Generator, could produce the same amount of power as an existing RTG using one-fourth the plutonium.
“Certainly the idea of being able to have a dynamic converter is something that we’ve been talking about for a long time,” said Ralph McNutt, chief scientist for space science in the space exploration sector at the Applied Physics Laboratory who co-chaired a 2009 study on the future of radioisotope power systems. “The problem is these have always fallen short” for technical reasons.
Another issue is potential additional demand for plutonium-238. NASA’s projected demand for the isotope dropped from 5 to 1.5 kilograms a year after the end of the Constellation program, which forecast the need for power systems to support human lunar exploration, McNutt said. (...)
http://spacenews.com/plutonium-supply-for-nasa-missions-faces-long-term-challenges/