Fairly simple to produce, except getting the fuel: https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Criteria_for_selection_of_isotopes http

Fairly simple to produce, except getting the fuel: https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Criteria_for_selection_of_isotopes https://en.m.wikipedia.org/wiki/Radioisotope_thermoelectric_...