Results with BWR fuel improvements

A large experience base coupled with extensive development resources has provided the base for improving GE Zircaloy-2 clad boiling water reactor fuel to achieve high fuel reliability in a commercial power reactor environment. The design of the assembly has proven an excellent choice and the same basic structural features have been continued from the mid-1960's through the present 8x8 fuel assembly design. As previously reported, hydriding and pellet-cladding interaction are the causes of defects which have been affecting the recent performance of fuel. The GE boiling water reactor fuel now being produced incorporates improvements in design and manufacturing; and BWR optimization studies resulted in an (8x8) fuel bundle design with lower peak heat generation rates. Early experience in the operating reactors on fuel with the improved design, and the reduction of peak thermal duty so that fuel performance requirements are generally within statistically demonstrated capability, gives confidence that a high degree of reliability can be expected for the fuel currently in production. (author)