Construction - a major bottleneck in data centre growth

The single biggest structural bottleneck for new data centres is access to reliable, high-capacity grid power, without which a data centre is just a warehouse. The scale of demand from new facilities has overwhelmed the UK’s grid connection process, creating delays.

Developers are joining enormous queues for connections with network operators and the regulator, Ofgem. Many face waits that stretch well into the next decade, with some connection offers dated for the late 2030s. This uncertainty makes it very difficult for many to finalise project timelines and secure investment.

The problem is particularly acute in key economic areas. Power-hungry corridors like the M4 and regions such as London and the south east are facing severe grid capacity constraints. This has forced some developers to either abandon preferred sites or accept that power availability will dictate their build schedule. While reforms are underway to prioritise projects that are ready to proceed, the backlog is immense. Without a confirmed power supply, lenders and developers are understandably reluctant to commit the vast capital needed for construction.

Power may be the most obvious constraint, but a data centre is useless without high-capacity fibre networks to move data in and out; and this critical component is now a significant source of delay. A recent survey revealed that 82% of UK data centre operators have postponed builds or expansions due to a lack of adequate fibre connectivity.

While major hubs are well-served, many other regions lack the dense core fibre infrastructure required to support the massive data flows generated by AI and large-scale workloads, and this is limiting geographic diversity for new developments.

The UK’s planning system has struggled to keep pace with the scale and technical complexity of modern data centre projects. Data centres are not always clearly defined within existing planning use classes, meaning they can end up competing with proposals for housing, industrial, or commercial land, leading to longer and more complicated review cycles.

Many local authorities lack the specialist expertise or resources needed to evaluate and fast-track such technically complex applications. This is compounded by political pressure to balance digital infrastructure growth with other local priorities like green spaces, housing targets, and sustainability goals. As a result, data centre plans face increasing scrutiny and delay. The situation has prompted calls within government to establish a dedicated planning use class for data centres to help streamline approvals and recognise their unique role as critical national infrastructure.

The data centre boom is happening at a time when the UK construction industry is already facing a severe skills shortage. The specialised trades required for these projects are in particularly short supply – experienced electrical and mechanical engineers, HVAC technicians, and constructors with data centre experience are highly sought after.

This scarcity creates intense competition for talent, driving up costs and putting pressure on project schedules. The complex mechanical and electrical (M&E) fit out constitutes a huge portion of a data centre build, and a lack of qualified people to execute this work is a material risk. When this is combined with high demand across all major infrastructure sectors – including energy, transport, and housing – recruitment becomes a significant factor in project delays.

The global demand for data centre components has created a challenging supply chain environment. Certain critical pieces of equipment have exceptionally long manufacturing and delivery timelines, which can have a domino effect on an entire construction programme.

Key items like generators, transformers, and high-voltage switchgear often take many months to procure. The rise of AI is driving demand for larger, higher-density facilities, which in turn require more powerful and often bespoke cooling systems, power distribution units, and networking hardware. These specialised components also come with extended lead times. If a single critical item arrives late, the entire construction schedule can slip, forcing costly and complex adjustments to the project plan.

The UK’s commitment to achieving net zero adds another layer of complexity and potential delay to data centre development. Operators are under increasing pressure to demonstrate the sustainability of their facilities, from planning through to operation.

This involves securing low-carbon power sources, such as through renewable energy power purchase agreements (PPAs), and designing facilities that meet stringent environmental targets. Environmental impact assessments are becoming more detailed, requiring in-depth analysis of factors like water usage for cooling, local biodiversity, potential for heat reuse, and overall emissions. While essential for responsible growth, this heightened focus on compliance and sustainability adds time and complexity to the pre-construction and planning phases.