Small Power Reactor Association Website is launched

Date: Jun 10, 2005

Small Power Reactor Association Website is launched

Dusty · Veteran Member

I like these HTGR's from GA.

There is however one small problem as I see it

These reactors seem to be based on a "once through" fuel cycle concept utilising recycled bomb Pu or LEU at around 20% enrichment. (I am not sure what the burn up percentage is likely to be)

Unfortunately Reactors based on this concept are not going to become the basis for a long-term nuclear energy strategy due to scarcity of material.

For a long term, large scale strategy we need to be able to use somehow nearly all the uranium not just 1-3% of it (correct me if I am wrong, but each ton of LEU leaves behind around 40 tons of "unusable" DU)

This means that HTGHR will need to be used in association with more conventional reactors such as CANDU that can burn natural uranium along with reprocessing and plutonium extraction.

For a large scale, long term programme, reprocessing and “Natural” uranium/thorium reactors are going to remain an essential part of the cycle.

Dusty

10kBq Jaro · Senior Member

I'd say you've got that about right Dusty..... Its just that there is enough uranium around to run the HTGRs for quite a few decades. It will also be possible to recycle the irradiated HTGR fuel eventually -- if the fresh fuel has an enrichment level of 20%, then the spent fuel will be about 16% U-235. This represents a huge burnup, far greater than today's PWRs, but of course there's lots of value still left in 16% enriched uranium..... There will also be quite a lot of plutonium in the spent fuel, since the other 80% is U-238, and some Pu-238 will also come from non-fission neutron capture by U-235.