RWE turns to Prysmian for 227-km Sofia export cable

The export cable for the offshore windfarm on the Dogger Bank in the North Sea will be installed by Prysmian’s new cable installation vessel Leonardo da Vinci, which is due to enter service in 2021.

The companies signed a preferred bidder agreement on 17 November 2020 for the design, supply, offshore route preparation, installation, commissioning and protection of the 320-kV high voltage direct current (HVDC) cable system that will carry power from the Sofia offshore converter station 227 km to an onshore converter station in Teesside.

The agreement includes symmetrical monopole HVDC submarine and land export cables, the latter using new eco-sustainable cable technology.

The contract involves more than 440 km of ±320 kV submarine export cables with XLPE insulation, and 15 km of ±320kV land cables with P-Laser insulation, plus communications cables.

Prysmian Group chief commercial officer projects Detlev Waimann described P-Laser as “the first 100% recyclable, eco-sustainable, high-performance cable technology.” It is based on the use of a patented thermoplastic material, high performance thermoplastic elastomer and on a zero-emission process that reduces CO₂ emissions by 40%.

“This project sets an important technological milestone in the offshore wind industry, being the first ± 320-kV DC offshore windfarm using P-Laser cable technology onshore,” Mr Waimann said.

Onshore construction will get underway at Sofia’s converter station site in Teesside early in 2021, with offshore construction anticipated to start in 2023. Installation and commissioning of the HVDC export cable is due to be take place in 2024.

The export cable announcement follows news that a consortium of GE’s Grid Solutions and Sembcorp Marine will supply Sofia’s HVDC transmission system and Siemens Gamesa Renewable Energy will supply the windfarm with SG 14-222 DD offshore wind turbines.