Enhancing proliferation resistance in advanced light water reactor fuel cycles

Alternative once-through, light water reactor fuel designs are evaluated for capability to reduce the amount and quality of plutonium produced. Doubling the discharge burnup is quite effective, producing modest reductions in total plutonium and significant increases in {sup 238}Pu whose heat generation and spontaneous neutrons complicate weapon usability. Reductions in the hydrogen to heavy metal ratio are counterproductive. Increases are helpful, but only small changes can be accommodated. Use of ThO{sub 2} in a homogeneous mixture with UO{sub 2} can reduce plutonium production to about 50% of that in a typical present day PWR, and in heterogeneous seed-blanket designs can reduce it to 30 to 45%. (author)