Sumitomo Opens the Nigg Factory Before Cable Production

Sumitomo Electric opened the UK’s first HVDC subsea cable factory at Port of Nigg on 19 October 2026, a £350 million plant that will not wind cable until 2027. The Japanese group’s Scottish unit, Sumitomo Electric UK Power Cables, put the hall on the Cromarty Firth inside the Inverness and Cromarty Firth Green Freeport.

First Minister John Swinney and Scottish Secretary Douglas Alexander attended with Sumitomo president Osamu Inoue and group chairman Masayoshi Matsumoto. The political line was jobs and energy security. The industrial line is thinner: SSEN Transmission’s Shetland 2 link is the anchor order, and the factory still has to wait for a 2026 call-off and a second-quarter 2027 start on the line.

The Factory on the Cromarty Firth

The plant sits at the Port of Nigg in Easter Ross, a deep-water yard on the firth north of Inverness. Sumitomo Electric Industries, based in Osaka, announced the project on 27 April 2023 and broke ground on 14 May 2024. The the official opening of the Nigg factory closed that build on 19 October 2026.

Japan’s consulate in Edinburgh, after a June 2026 site visit, described a 58,000 square metre hall on a 15-hectare plot, a footprint it compared to 22 football pitches, and called Nigg the group’s main European base for this product. The line is rated at 525kV HVDC, the voltage class now specified on the UK’s long subsea links. Until this hall opened, National Grid said, HVDC transmission cable had not been made in the UK for around 20 years.

THE NIGG HALL IN FIGURES

• The cheque: Sumitomo puts the investment at £350 million, about 70 billion yen.
• The floor: 58,000 square metres of plant on a 15-hectare Port of Nigg site.
• The product: 525kV HVDC subsea cable, with inter-array cable also in the plan.
• The payroll: Sumitomo said the opening would create up to 250 direct jobs and support more than 400 roles in the wider supply chain.

Inoue used the ceremony to fix the dates in public. He said he was “delighted to celebrate the official opening of our new subsea cable factory in Scotland, following the announcement of its establishment in April 2023 and the groundbreaking ceremony held in May 2024,” and that the hall would be “a vital production base supporting the strengthening of the UK’s transmission infrastructure.”

I am delighted to celebrate the official opening of our new subsea cable factory in Scotland, following the announcement of its establishment in April 2023 and the groundbreaking ceremony held in May 2024. This factory will serve as a vital production base supporting the strengthening of the UK’s transmission infrastructure, the expansion of renewable energy deployment, and the delivery of a stable and reliable energy supply for generations to come.

Osamu Inoue, President, Sumitomo Electric Industries, Nigg opening ceremony

Swinney called the plant “a strong vote of confidence in our people, skills and engineering excellence.” Alexander said Scotland was “helping to solve one of the biggest challenges in our transition to clean energy, connecting offshore wind to where it’s needed most.” Jamie Stone, the Liberal Democrat MP for Caithness, Sutherland and Easter Ross, said he had worked at Nigg and took part in a Kagami-biraki barrel-opening on the floor.

Great to open Sumitomo’s new subsea cable factory in the Highlands – bringing hundreds of new, well-paid jobs to the area and helping unlock Scotland’s huge offshore wind energy potential. pic.twitter.com/RCXN0twk6H

— John Swinney (@JohnSwinney) October 19, 2026

Shetland 2 Underwrote the Highland Plant

The hall exists because a grid company booked it. On the May 2024 groundbreaking day, SSEN Transmission, the SSE transmission business that runs the north of Scotland network, named Sumitomo and Dutch installer Van Oord Offshore Wind UK as preferred bidders for Shetland 2, a second 525kV HVDC link from Shetland to the mainland. SSEN said that order was “the anchor project supporting and enabling” the Nigg investment.

The independent system operator had already confirmed the need for a second Shetland HVDC circuit in its Beyond 2030 plan. SSEN said the link would also help connect three ScotWind sites next to the islands. Sumitomo has described the route as about 330 km of 525kV cable.

Rob McDonald, managing director of SSEN Transmission, put that history on the record at the opening and tied the plant to a much larger north-of-Scotland spend.

The opening of Sumitomo Electric’s new cable manufacturing facility is a landmark moment, not only for Scotland’s energy transition but for its economy too – and we’re proud of the role our proposed Shetland 2 subsea cable project played as an anchor for this investment.

Rob McDonald, Managing Director, SSEN Transmission, Nigg opening ceremony

On 9 July 2026 the same three parties signed an HVDC framework. They said they expect a call-off contract in 2026 for Shetland 2 cable, subject to regulatory approvals, and a manufacturing start in the second quarter of 2027 at Port of Nigg. McDonald said SSEN Transmission is investing around £29 billion over the next five years. A capacity reservation in January 2025 had already locked factory time, and SSEN said construction spend on the hall to that point was split 55% in Scotland and 45% in the rest of the UK and Ireland.

Masaki Shirayama, managing director of Sumitomo Electric, pointed to a Glasgow engineering centre beside the Nigg hall as proof the group meant to stay. The factory is the bet. Shetland 2 is the first chip on the table, and it is still a proposed link until that call-off is signed.

National Grid Books a Kent-to-Suffolk Cable

The second booked job sits at the other end of the country. National Grid Electricity Transmission named Sumitomo preferred bidder on 16 July 2025 for Sea Link, a 2GW link between Kent and Suffolk running through the Thames Estuary and the southern North Sea. Sumitomo said on 11 December 2025 that it had signed a contract to supply and install 140 km of 525kV HVDC cable, to be made at Nigg, with construction scheduled to begin in 2027. Siemens Energy has the converter stations. Van Oord has the marine spread.

Carl Trowell, executive president of global capital at National Grid, told the Nigg ceremony the group had placed more than £28 billion of UK supply-chain contracts, and that awarding Sea Link to Sumitomo “reflects the confidence that long-term investment can provide.” Shirayama’s earlier line on Sea Link was blunt: “Our plan is to manufacture and supply 525kV HVDC cable from our factory in the UK.”

THE TWO GRID JOBS ON NIGG’S BOOKS

Those two circuits are the commercial case for a Highland hall that would have been a stranded asset without them. They are not, on their own, a cure for a European cable queue that still runs years ahead of UK wind farms.

Why the UK Still Queues for HVDC Cable

Miatta Fahnbulleh, Secretary of State for Energy Security and Net Zero, said making subsea cables in Scotland “will help us tackle the bottlenecks that block electricity from being transported across the country.” The department’s own homework is less tidy. the 2026 supply chain readiness study, commissioned from Baringa Partners and published on 30 April 2026, found that HVDC export-cable constraints had eased only slightly as new plants opened in Europe and Asia.

Lead times remained long. Modelling in the study suggested supply still could not cover combined demand from offshore wind, grid upgrades and interconnectors. It recorded a severe HVDC shortfall in 2025 and a significant shortfall in 2026, with capacity improving only after that as engineering resource and standard designs catch up.

WHAT STILL SITS IN FRONT OF THE CABLE

• Shared demand: Wind farms, onshore grid upgrades and interconnectors are bidding for the same HVDC lines.
• Long leads: New European and Asian plants have helped, but the 2026 study said lead times are still long.
• A 2026 gap: Baringa modelled a significant HVDC shortfall in 2026, after a severe gap in 2025.
• A later start: Nigg’s own line is not due to run until the second quarter of 2027, so it does not close that 2026 gap.

Nigg is also not the UK’s only new cable shed. JDR Cable Systems opened a £130 million plant at Cambois, near Blyth, in June 2026 for longer, higher-voltage AC and inter-array systems. That is a different product. HVDC export cable is the scarce piece, and Nigg is the first UK hall built for it. Nexans, in the same month as the Nigg ceremony, began industrial-scale 525kV HVDC output at Halden in Norway for TenneT’s LanWin2. The European line is already turning. The Highland line is not.

Public Money and Green Freeport Relief

Holyrood and Whitehall both claimed the opening, because both paid. Swinney said the Scottish Government “invested £24.5 million in its construction.” Highlands and Islands Enterprise, when the grant was agreed in early 2024 after Highland Council planning approval on 17 January 2024, set out a split of £19.37 million from the Scottish Government, £4.6 million from HIE and £0.53 million from Scottish Enterprise.

Alexander stressed a different cheque: the Port of Nigg sits in the Inverness and Cromarty Firth Green Freeport, which received £25 million of UK government seed funding. That seed is for the freeport, not a direct payment to Sumitomo. Inside the tax site, customs and tax rules are lighter than in the rest of the UK, which both governments cited as part of the reason the Japanese group chose Nigg. The Scotland Office billed the day as industrial strategy. Swinney billed the Scottish grant. Both were on the platform.

The same east-coast industrial push now includes a Montrose plant for wind anchors, another port-side bet that offshore wind hardware should be made next to the water it will enter. Nigg is the HVDC version of that wager, underwritten by a capital grant, a freeport seat and two named grid contracts rather than by a spot market for cable.

Matsumoto, the group chairman, said Sumitomo would “further deepen and strengthen our relationships with local stakeholders through hundreds of job creation, workforce development along with significant sustainability contributions.” The jobs figure the company put on the opening remains up to 250 on the floor and more than 400 in the chain. McDonald, speaking for the anchor customer, said the plant would create “at least 200 jobs and support hundreds more.” Those lines can both be true. Neither is a headcount of people already on shift.

Cable Will Not Leave Nigg Until 2027

An open factory is not a loaded drum. Sumitomo and SSEN Transmission have said, in the July 2026 framework, that Nigg cable for Shetland 2 should start in the second quarter of 2027. Sea Link construction is also scheduled from 2027. The call-off that turns Shetland 2 from a reserved slot into a manufacturing order is still expected in 2026, and it still depends on regulators.

HOW THE NIGG BET WAS PLACED

1. 27 April 2023: Sumitomo Electric announces a power-cable factory in Scotland.
2. 14 May 2024: Groundbreaking at Port of Nigg; SSEN Transmission names Sumitomo and Van Oord preferred bidders for Shetland 2.
3. 16 July 2025: National Grid names Sumitomo preferred bidder for Sea Link.
4. 11 December 2025: Sumitomo signs the Sea Link supply-and-install contract for 140 km of 525kV cable from Nigg.
5. 9 July 2026: SSEN Transmission, Sumitomo and Van Oord sign an HVDC framework; cable making is set for the second quarter of 2027.
6. 19 October 2026: The Nigg factory opens.
7. Second quarter of 2027: Sumitomo expects manufacturing to start at Port of Nigg.

SSEN Transmission and the consortium still expect that 2026 call-off for Shetland 2, subject to regulatory approvals, before the line at Nigg is asked to run.

Frequently Asked Questions

What Types of Cable Will the Port of Nigg Factory Make?

The hall is built for 525kV HVDC subsea transmission cable, the class used on long, high-power links such as Shetland 2 and Sea Link. Japan’s consulate in Edinburgh, after inspecting the site on 3 June 2026, said the plant will also make inter-array cables that connect individual offshore turbines, so Nigg is not limited to the export cores that grid companies buy.

How Was the £24.5 Million Scottish Grant Split?

Highlands and Islands Enterprise said the public package was £19.37 million from the Scottish Government, £4.6 million from HIE and £0.53 million from Scottish Enterprise, paid toward construction after planning approval in January 2024. That grant is separate from the £25 million of UK government seed funding for the Inverness and Cromarty Firth Green Freeport as a whole.

Where Is Sumitomo Electric’s Scottish Office?

Sumitomo Electric UK Power Cables lists its office at Cromba House, 4 River Drive, Alness, with the factory at Nigg, Tain. The subsidiary was set up in 2023 to run the Highland project, and Consul General Katsutoshi Takeda visited the new Alness office and the unfinished Nigg hall on 3 June 2026.

How Does Nigg Differ From JDR’s Blyth Cable Plant?

JDR Cable Systems opened a £130 million factory at Cambois, near Blyth, in June 2026 to expand AC, inter-array and higher-voltage land and subsea systems. Nigg is the first UK plant built to make HVDC subsea transmission cable, the product National Grid said had been imported for around 20 years, so the two halls sit on different parts of the same shortage.

Who Will Install the Cables That Nigg Produces?

Van Oord Offshore Wind UK is Sumitomo’s installation partner on both named jobs: the Shetland 2 framework with SSEN Transmission and the Sea Link marine work for National Grid. Siemens Energy is building Sea Link’s converter stations in Kent and Suffolk, which sit at the ends of the Nigg-made cable rather than in the Highland hall.