Improvements in or relating to a method of operating a nuclear reactor which maintains a substantially constant axial power distribution profile which changes with load

The invention provides an improved procedure for operating a nuclear reactor that provides substantially symmetric axial xenon distribution during reactor operation including load follow. The desired xenon distribution is accomplished by maintaining a relatively uniform axial power distribution during load follow manoeuvrers, which minimizes total peaking factors and thus avoids power penalties. Furthermore, operating within the specified limits prescribed by the steps of this invention simplifies nuclear analysis procedures, minimizes pellet-cladding interaction effects, and reduces the probability of hitting plant alarm limits which can interrupt plant operation. (J.R.)