“Have you heard of a Pebble Bed Reactor (PBR)?.................”
Yes South Africa, Germany both had experimental ones, China has two in experimental status right now.
TRISO fuel is impressive it can get to crazy high burn ups....maximum burnup for TRISO fuel is around 20% FIMA (fissions per initial heavy metal atom)
Huge fan, can’t melt down, reaches 1000C temps with either helium or molten salt cooling so industrial heat and more importantly heat storage tech works with it.
Take the graphite out and use silicon carbide for the buffer and shells and chloride salts you can also do fast spectrum or epithermal spectrum. Breed ratio is not as good as a liquid metal fast reactor but it is above 1 so once you start it you only need depleted uranium supplies.
Problem is C14 all that graphite in the pebbles gets irradiated and a good amount of it ends up as C14 and 5000 year half life’s not ideal given how biologically active carbon is.
It’s also super difficult to reprocess pebbles they resist nitric acid you have to crush and burn the graphite out and the silicon carbide too. Then you have CO2 gas that’s loaded with C14 carrying CO2 that is a disaster waiting to happen you need to turn all that CO2 back to solid graphite and bury it in a medium level waste storage repository for at least 10 half lives so 50,000 years this is the valid argument against pebble bed reactors.
Or launch it into the Sun..................