The reactor at EDF Energy’s Sizewell B plant is more than capable of generating electricity beyond its original design life. However, its existing fuel storage pond was approaching full capacity and an alternative means of storing spent fuel was therefore required.
EDF’s Dry Fuel Store project would achieve this – however, the safe lifting, transportation and final positioning of the new, specialised dry fuel casks was a complete change of use for the original 28-year-old, 152-tonne fuel building crane.
SCX was commissioned to perform a complete overhaul and upgrade of the original crane’s control and protection systems. This required an extensive design, testing, installation and commissioning programme, for one of the most complex contracts that SCX has ever undertaken.
The Safety Case for handling the fuel casks introduced a number of new Safety Functional Requirements (SFRs) into the crane’s new specification. These were met by a three-tiered Nuclear Protection System, where the crane’s new control system, plus two independent and diverse layers of hard-wired protection, all contributed to achieving the specified nuclear safety targets.