Some alternatives to the mixed oxide fuel cycle

Abstract

and accountability problems. These could, i n turn, lead t o fuel licensing problems and probably derating of existing HWR designs. B u t new HWRs ._ would undoubtedly be b u i l t to minimize the economic penalties of derating (i. e. , increase core size, b u t design other plant components for the "derated" power 1 eve1). One advantage of the refabrication tandem cycle i s t h a t , by starting with existing HWR designs, the HWRs could s t a r t coming on line by perhaps the mid-1990s. However, i f a HWR i s designed t o u t i l i z e spent LWR fuel as i s , the plants would not be coming on line before a t l e a s t the year 2000 because of the time required for design, development, demonstration, and licensing of a new reactor concept. This concept would eliminate the costly refabrication step and improve fuel r e l i a b i l i t y. B u t i t would s t i l l not be as good as that of fresh fuel, thus the HWR i s s t i l l penalized. Finally the capital costs of HWRs are a t l e a s t 10% higher than those of LWRs and uranium requirements a r e higher. The net r e s u l t i s a decided economic and environmental penalty f o r the tandem cycle, probably even by comparison to the throwaway cycle (A1 ternative 6). Extended Burnup-Extended b u r n u p of LWR fuels could conceivably be achieved by: (1) additional shuffling of fuel elements, rods and rod segments w i t h i n the core to a t t a i n a higher average burnup; or (2) higher i n i t i a l enrichments, or spike enrichments,used to drive the core to longer burnups.