Italy’s Prysmian has completed the North Sea Link (NSL) interconnector between Norway and the UK ahead of schedule.
In 2015, Norwegian system operator Statnett and UK’s National Grid awarded Prysmian with a €550 million project to deliver approximately 950 kilometers of subsea HVDC cables (1400MW, ± 525kV) for what is said to be the world’s longest submarine electricity interconnector.
The cables were manufactured at Prysmian’s Arco Felice Factory in Naples and installed in the North Sea over a 720-kilometer route.
According to Massimo Galletta, project manager at Prysmian, the company put together an accelerated schedule that allowed the installation of the NSL interconnector to be completed some 9 months ahead of the contract schedule.
“The plan in 2015 was to complete the work in line for commissioning in 2021. While the timescale looked quite healthy, the initial years were committed to the design and manufacture of the system and considering how best to execute the work once the cable was manufactured,” Galletta said.
“When we performed our risk assessment on the execution phase we looked at the risks toward the end of the installation phase and established that we could significantly de-risk the project by performing some of the work in earlier years.”
In October 2020, Prysmian received the certificate marking the completion of the installation works. With the execution of the transition joints between Prysmian and Nexans cables in Q2 2021, the trial and commission phase started as planned in Q4 2021 and was successfully concluded.
At the completion of commissioning operations and delivery of the As-Built documentation, Prysmian received the Completion Certificate on 14 February 2022, one month ahead of the contractual milestone.
The 1,400 MW North Sea Link runs between the Suldal municipality in Norway and the Newcastle area in England. It enables the sharing of renewable energy between the two countries for the first time.
The 720-kilometer interconnector was completed in early June 2021 and on 18 June transmission between Norway and the UK was tested for the first time.