The former Blyth Power Station site at Cambois was once meant to be one of Britain's major electric-vehicle battery sites. Britishvolt secured a conditional government funding offer in January 2022 for a gigafactory that ministers said would make enough batteries for more than 300,000 electric vehicles a year.

The company entered administration in January 2023 after failing to secure enough private investment to meet the funding milestones. The same site is now becoming a major data-centre project.

QTS Data Centers, backed by funds managed by US investment firm Blackstone, is developing a campus on the site with outline planning permission for up to ten data-centre buildings. The stated investment attached to the project is up to £10bn. QTS and Invest Northumberland describe the full campus as 720MW of capacity, with each building designed for 72MW.

Northumberland County Council approved outline planning permission for the campus in March 2025. Enabling works began in October 2025, and reserved matters for the first two data-centre buildings were granted in January 2026.

QTS says earthworks are continuing during 2026 and that it will start construction of the first data-centre building this year. The full ten-building campus remains a staged programme, but the first phase is now moving through planning and construction.

Several different names overlap at Cambois, and they are easy to confuse.

The QTS campus is the data-centre project on the former Blyth Power Station land. The same broad site had previously been earmarked for Britishvolt's electric-vehicle battery factory before the company entered administration. The Northumberland Strategic Investment Site, or N-SIS, is a separate 77-hectare council-owned development site next to it. The North East AI Growth Zone is the wider government designation covering sites at Blyth and Cobalt Park near Newcastle.

Those three things are linked but distinct. The QTS campus is the anchor, N-SIS is the neighbouring industrial land Northumberland is marketing for large occupiers, and the AI Growth Zone is national government policy intended to speed planning, grid connection and investment around AI infrastructure.

Northumberland wants the QTS campus to strengthen the case for investment in the surrounding industrial land.

Data centres need land, power, fibre, cooling and security. They do not need a city-centre labour market in the way an office scheme does, and they do not work like a factory.

Cambois has some of the features a large data-centre operator wants. It is a large brownfield site with a power-station legacy. It sits close to the Port of Blyth, Energy Central, offshore wind supply chains and major industrial land. Northumberland is also presenting the site as part of a wider clean-energy and digital infrastructure cluster.

QTS says its Cambois campus will use closed-loop cooling, reducing pressure on local water supplies, and that it will explore the use of waste heat for a possible district heating network with Northumberland County Council. Both remain commitments, not yet proven benefits. Heat reuse from data centres can be valuable, but only if there is a practical local heat network and users close enough to take it.

The same caution applies to the AI Growth Zone itself. The government has said the North East designation could support more than 5,000 jobs and attract up to £30bn in private investment. That larger figure includes more than Cambois.

It also includes Cobalt Park near Newcastle and wider AI investment plans. Those plans have already shifted once. In April 2026, ministers told Parliament the programme was not dependent on one investor after OpenAI paused its Stargate UK investment.

For Cambois, the more useful figure is the QTS number: up to £10bn of investment if the full campus is delivered.

The outline permission approved by Northumberland covers up to ten Class B8 data-centre buildings, with up to 540,000 sq m of gross internal area, plus ancillary structures, a substation, emergency generators and associated works.

The first detailed approval is smaller and more concrete. Northumberland granted reserved matters approval for the first two phase-one data-centre buildings, including office space, a security gatehouse and infrastructure, on 8 January 2026.

Further 2026 applications point to an accelerated programme. Planning notices show additional enabling works for later phases, including site preparation, earthworks and piling. fDi Intelligence has reported that QTS also applied to update parts of the outline consent so four of the ten buildings could be ready by 2030.

The later buildings remain less certain than the first phase, as is typical for staged data-centre campuses that advance as demand, power capacity, customers and capital are secured.

The economic case is different from the one Britishvolt offered.

Britishvolt was a manufacturing promise: a gigafactory, a large production workforce and a place in the electric-vehicle supply chain. QTS is an infrastructure promise: large capital spend, construction activity, specialist operational jobs and the possibility that the surrounding land becomes more attractive because a global digital-infrastructure investor is already there.

QTS's own public material says the Cambois campus is expected to create about 1,200 construction jobs and 400 operational jobs, with up to 2,700 indirect jobs. It has also said it is committed to recruiting locally within 25 miles of the site where possible. Invest Northumberland separately says QTS has helped establish a £110m fund to drive long-term local investment.

Data centres are capital-intensive. Most of the spend is in land, buildings, electrical equipment, cooling systems, security, fibre and servers, so direct operational headcount is modest relative to cost.

For Northumberland, the long-term gain is likely to be a mix of construction work, specialist maintenance, electrical and mechanical contracting, data-centre skills, business rates and local supply-chain spend. The harder test is whether the campus helps create an economy around it, rather than remaining a single large infrastructure asset.

Northumberland is marketing the neighbouring 77-hectare N-SIS site as more than 3.25m sq ft of industrial development space, close to the Port of Blyth, Energy Central, the Northumberland Line, offshore wind assets and the QTS campus. The question is whether QTS helps N-SIS attract occupiers, or whether the adjacent site can attract them independently.

Data centres are contested because they are big, enclosed and power-hungry. They bring construction traffic, security fencing, noise questions, visual impact and demand for grid capacity. Residents can also see fewer visible long-term jobs than the headline investment figure implies.

The Northumberland planning papers show that those issues have already appeared. The outline committee record refers to objector concerns, fire protocols, air quality, noise, emergency-generator testing, biodiversity net gain and the treatment of the site's former ash mounds.

Those concerns need to be weighed against the alternative uses for a former power-station site that has already seen a failed gigafactory plan.

Cambois is not a greenfield business park. The choice is among different uses for one of Northumberland's most important industrial sites, not between a data centre and an untouched village edge.

The next milestone is construction of the first data-centre building. QTS says that will start in 2026. The second is the delivery timetable for the first two buildings, where public sources currently point to operations beginning in the late-2020s. The third is whether the 2026 acceleration applications are approved and whether buildings three and four move forward on the faster programme described in the April 2026 planning material reported by fDi.

After that, the questions become economic. How many local firms win work? How many apprenticeships and training places materialise? How much of the operational workforce is drawn from the surrounding area? What does the £110m local investment fund actually fund? Does waste heat reuse become a real scheme? Does QTS help N-SIS attract occupiers?

Cambois is going ahead as a data-centre site, at least through phase one. The full promise remains larger than what has been delivered so far.

What is QTS building at Cambois? A data-centre campus on the former Blyth Power Station site, near Cambois and Blyth, with outline permission for up to ten buildings.

Who owns QTS? QTS is owned by funds managed by Blackstone, which completed the acquisition of QTS Realty Trust in 2021.

Is the project definitely going ahead? The first phase is clearly moving ahead. Outline permission has been granted, enabling works began in October 2025 and reserved matters approval for the first two buildings was granted in January 2026. The full ten-building campus remains a staged programme.

How big is the full campus? The outline consent covers up to 540,000 sq m of gross internal area. QTS and Invest Northumberland describe the campus as up to £10bn of investment and 720MW of capacity.

How many jobs are expected? QTS says the project is expected to create about 1,200 construction jobs, 400 operational jobs and up to 2,700 indirect jobs.

How does this relate to Britishvolt? The same former power-station site was previously earmarked for Britishvolt's battery factory. The economic promise has changed from manufacturing to digital infrastructure.

How does this relate to the North East AI Growth Zone? The QTS site at Cambois is part of the wider North East AI Growth Zone, alongside Cobalt Park near Newcastle. The Growth Zone is a government designation intended to support AI-enabled data centres and related infrastructure.