My understanding is that radioactive waste volumes & activity differ based on reactor type. Light-water reactors (PWR/ BWR) only burn 3% of the fuel energy henc

My understanding is that radioactive waste volumes & activity differ based on reactor type. Light-water reactors (PWR/ BWR) only burn 3% of the fuel energy hence leaving large energies as mid- and high-level radioactive waste. Heavy-water reactors such as CANDU can achieve greater burn-up, can avoid enrichment, and even reportedly burn waste from PWRs as fuel. There are downsides but to my mind they seem small. https://en.m.wikipedia.org/wiki/CANDU_reactor#Fuel_cycle https://en.m.wikipedia.org/wiki/CANDU_reactor#Fuel_cycle