Oooof, looks like the primary way of creating it is through... fission reactors. https://en.wikipedia.org/wiki/Tritium#Production https://en.wikipedia.org/wiki

Oooof, looks like the primary way of creating it is through... fission reactors. https://en.wikipedia.org/wiki/Tritium#Production https://en.wikipedia.org/wiki/Tritium#Production And there's not much of it: > According to a 1996 report from Institute for Energy and Environmental Research on the US Department of Energy, only 225 kg (496 lb) of tritium had been produced in the United States from 1955 to 1996.[a] Since it continually decays into helium-3, the total amount remaining was about 75 kg (165 lb) at the time of the report.