Ark Data Centres will invest GBP £807 million to expand its Longcross Park campus in Surrey, supporting a larger deployment by AI cloud provider Nebius.
Ark has committed GBP £335 million so far and earmarked a further GBP £472 million for the site. The expansion includes vertical extensions to existing buildings, upgrades to supporting infrastructure, and a separate 36MW data centre facility known as LP02.
Nebius is increasing its UK footprint through the Longcross campus and will fully occupy its existing facility there. The move follows an initial deployment at the site that is already live and operational.
AI demand
Longcross has become one of Ark's key sites for AI-related computing demand. The campus supports intensive AI workloads across sectors including healthcare and scientific research, with applications ranging from earlier disease detection to data-led drug discovery.
The investment adds to a broader push to expand UK data centre capacity as demand rises for infrastructure that can support AI systems and large-scale computing. Operators are seeking more power, more space, and planning approvals that allow them to increase density at existing campuses.
Capacity growth
Planning approval in this case covers both the expansion of current buildings and the addition of the new facility. The work is intended to accommodate higher-density deployments while keeping the campus layout and environmental framework in place.
The project also highlights the growing role of specialist data centre operators in serving cloud companies that need large volumes of computing equipment without building every site themselves. Nebius, which focuses on AI cloud services, is using the Surrey campus as part of its UK growth.
Ministers have identified AI infrastructure as an area where private investment is needed if the UK is to increase domestic computing capacity. That has brought data centres, electricity supply, and planning into sharper focus as policymakers try to support AI development while balancing local and environmental constraints.
Government backing
AI Minister Kanishka Narayan linked the project to that wider policy goal.
"The whole government is determined to create the right conditions for investment in the UK's AI and data centre infrastructure, to drive growth and create the jobs people deserve. Ark's investment at Longcross Park is an important part of this work. This will bring more cutting-edge compute to the UK, which is critical to our plans to empower workers and turbo-charge productivity," said Kanishka Narayan, AI Minister, UK Government.
Customer expansion
Ark's management said customer demand at Longcross has moved beyond early-stage testing into larger production use. The company presented Nebius's expansion as evidence that customers are scaling their deployments at the site.
"Demand for high-performance AI infrastructure is no longer theoretical - it is live, operational and growing. Seeing customers scale from initial deployments to full-building occupancy is a clear validation of what has been delivered at Longcross. Securing planning permission for the next phase of development allows us to build on that momentum and continue supporting customers as their requirements evolve, while reinforcing our long-term commitment to enabling advanced digital infrastructure in the UK," said Huw Owen, Chief Executive Officer, Ark Data Centres.
"The UK is an important market for AI development and deployment, and access to high-quality, operational infrastructure is critical to supporting that growth. Expanding our work with Ark ensures we can continue to scale our platform and support organisations building and applying AI at scale," said Andrey Korolenko, Chief Infrastructure and Product Officer, Nebius.
Ark was founded in 2005 and develops and operates data centres in the UK. It also works with the UK government through Crown Hosting Data Centres, a joint venture with the Cabinet Office.