Jersey Electricity: Normandie 3 Subsea Cable Installed

Normandie 3 is Jersey Electricity’s 10-year, £70 million project to lay a third interconnector to France, in partnership with Guernsey Electricity (GEL) as part of the Channel Islands Electricity Grid (CIEG), to secure imported supplies of low carbon, lower cost electricity for decades to come.

A very busy weekend has seen the Cable Enterprise at last touched down on Jersey ‘soil’. With the final checks complete and clearance from the beach teams to proceed, the vessel first ‘grounded-out’ about 1km from the shoreline on Friday.

There followed two days of gradual progress up the beach as the spring tides helped to place the Enterprise at her optimum position for off-loading the cable. This finally happened on Sunday afternoon just 200m off the seawall adjacent to Long Beach car park.

With the beach team of GPC Ltd ready and following the falling tide out to the stern of the vessel, the cable was lowered to the operatives at 14:00 and secured by a quadrant that had been sheet piled into the sand. With a second quadrant held aloft by tracked excavators and a line of rollers in place, over 500m of cable was hauled away, sufficient to reach the joint bay located in the car park with a little extra over just to make sure.

With a tidal window of just four hours, the whole operation was completed in just 120 minutes. This allowed the team on board to cut the cable and seal the ends ready for the final hand-off at 04:00 Monday morning. The beach teams then begin the process to realign the cable and plough it in up the beach to a depth of over 1.5m before it is winched through a pre-installed duct and into the joint bay where the land cable awaits.

With the cable end secured away from the stern of the Enterprise the assisting tugs Zwerver and Norne, with the Afon standing by, were alongside on the high tide. With beach anchors released and tow wires secured the Enterprise, minus over 32km of cable eased away from Grouville beach at 09:00 Monday morning. She will sit in safe water a couple of kilometres out from the castle while all equipment is sea-fastened and the beach anchors recovered and secured to her deck before departing Jersey waters early on Tuesday morning.

It’s not quite the end for the offshore project team as there is still 3km of spare cable in the carousel. This will be transported to Rotterdam before being loaded into specially designed storage pans where it is easily accessible in the unlikely event it is required for a repair. Once the Normandie 3 cable is clear from the Cable Enterprise she will be heading down to Croatia for a major refit.

With the completion of the installation of the subsea cable the final phases of the project start with the jointing of the cable to the land sections in both France and Jersey and the complex operation of testing and commissioning a combined circuit of almost 60km and a great deal of ancillary equipment.