The design net power output of the station was 626MWe, but due to steel corrosion problems from the hot carbon dioxide coolant within the reactor, operating temperature had to be reduced soon after operation started causing a large drop in power output. Initially power output was set at 424MWe, dropping to 400MWe by 1973. Then as remedial measures were adopted power was progressively increased to 434MWe by 1983 with a gas outlet temperature of , compared to the design temperature, which was maintained as the normal operational output.