I don't have the numbers reversed. I'm talking about when a single atom actually undergoes fission, it releases 93% of its energy promptly as fission product ki

I don't have the numbers reversed. I'm talking about when a single atom actually undergoes fission, it releases 93% of its energy promptly as fission product kinetic energy, gamma rays, and neutron kinetic energy. An hour later, another 6% of the energy goes out as delayed betas and gammas. After that, only 1% remains to emerge as heat in the repository. What you're referring to is the fact that some reactors (aka breeder reactors, fast or thermal) can fission a much higher percentage of the total atoms loaded into the reactor, including most of the majority isotope (U-238) in addition to the minority (U-235). I wrote a bit about breeding and recycling here: https://whatisnuclear.com/recycling.html https://whatisnuclear.com/recycling.html