The power produced by Sofia's turbines will be transmitted by offshore cables that make landfall at a site between Redcar and Marske-by-the-Sea. Each offshore cable connects to an onshore buried cable that runs seven kilometres to a new converter station, currently approaching completion on a site adjacent to the Wilton Centre, a science park in the North East of England. Further buried cables will transport the power two kilometres from the converter station to the existing substation at Lackenby, where it will feed into the national grid.
Onshore construction works began at the site of the converter station in June 2021, and onshore project-related activity will continue until the middle of 2026.
The onshore works for Sofia has been largely completed, with recent efforts focused towards the restoration and reinstatement of the environment, and finishing touches on the onshore converter station.
Onshore converter station (OCS)
Civil engineering contractors contracted to GE's Grid Solutions began work in spring 2022, readying the site for the installation of the converter station's state-of-the-art electrical infrastructure. Over the following three and a half years, the team there has fully constructed and commissioned the OCS, and it stands ready for the next stage of the project.
The Sofia team has tried hard to minimise disruption to those living nearest the site. Part of this has involved re-shaping the northern of two mounds that separate the converter stations’ site from Lazenby Village. As well as being reshaped, it has also been planted with trees, shrubs and wildflowers. The second phase of reshaping has completed, acting now to visually screen the two new converter stations and the Wilton International site.
400kV AC cable route
A second GE contractor, VolkerInfra successfully completed duct installation for the two-kilometre 400kV AC cable route from the converter station to the National Grid substation at Lackenby.
Cable route
All civil engineering works for the export cable route was completed in 2025.
Landfall
The landfall site has been fully reinstated, with the compound now removed. The artwork which was used to decorate the compound hoardings, created by students at the nearby Outwood Academy Bydales, has been reprinted, with a new set gifted back to the school in October 2025.
Start of enabling works to prepare for the construction of the converter station.
Start of work on the mounds on-site - to increase the screening of the converter station site from the village of Lazenby.
Enabling works completed at the converter station site.
Work at the existing National Grid Lackenby Substation begins.
Construction of Sofia’s onshore converter station begins.
Start of works along the cable corridor from landfall to Lackenby Substation. Trenching and duct laying underway.
Start of two years construction activity at the landfall between Redcar and Marske-by-the-Sea, including horizontal directional drill under the beach to lay ducts for the offshore cable.
Start of work to install the export cables from shore to the converter station.
Installation of AC cables from the converter station site to the National Grid substation.
Completion of construction works at the landfall site.
Completion of the installation of cables from shore to the converter station.
Sofia connected to the national grid. All work, including reinstatement, completed along the cable corridor between the converter station and substation, and at the substation itself.
Onshore converter station construction completed.
Completion of the mounds screening the converter stations.
Completion of reinstatement of cable corridor from shore to the converter station site.
Construction of the Onshore Converter Station completed
All relevant plans relating to the project's onshore construction, including Design, Landscape, Fencing and Drainage, will be submitted to Redcar & Cleveland Borough Council for approval prior to work starting. The button below takes you to a list of all the available documents and their reference numbers so you can find them in the Planning Register of the Council website.
| CONTRACTOR | DESCRIPTION | WEBSITE |
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Starting onsite in 2022, GE's Grid Solutions will be responsible for the construction of the onshore converter station. |
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Prysmian Group will design, supply, install and commission Sofia's HVDC export link including 15km of onshore cables and installation work. |
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Jones Bros Civil Engineering UK will deliver the enabling works package for the onshore converter station platforms for both Sofia and Dogger Bank C. |
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Kier is carrying out the onshore converter station civils construction package on behalf of GE's Grid Solutions. |
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VolkerInfra will design, supply and install the 400kV AC cable between Sofia's onshore converter station and National Grid's Lackenby Substation. |
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BakerHicks will design the Sofia onshore converter station and carry out related activities. |
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J. Murphy & Sons will design and deliver the onshore export cable civil works in relation to both Sofia and neighbouring project Dogger Bank C. |
