London, United Kingdom, September 15th, 2026, FinanceWire
Authority.inc, an industry forecasting platform, has published a new analysis of planning activity across London’s data centre market, tracking how project filings, approvals and refusals have moved through the city’s planning system over the past year, and where the real bottleneck to delivery now sits.
The analysis centres on Authority’s Planning Momentum Index, which combines first-time project filings and approvals, then subtracts refusals or withdrawals, to produce a single trailing 12-month score against a fixed 2021 to 2024 baseline of 100.
Momentum Remains Elevated, but Has Fallen Sharply From Its Peak
The index stood at 119.5 for the year to June 2026, roughly 20 percent above the historical baseline. That is a marked drop from a peak of approximately 259 recorded in early 2026, as a large wave of 2025 filings began rolling out of the trailing 12-month window faster than new activity replaced it.
Examining the Project Pipeline
Authority’s analysis monitors 50 qualifying data centre projects, joined from 566 matching public planning records into single project histories. As of the latest snapshot, 26 of those projects sit at the approved stage, 6 remain in planning, 10 have a recorded build-complete status, 1 has verified construction activity, 1 is pre-consent, and 6 have been refused or withdrawn. None currently has independently verified operational status within Authority’s planning register.
Among the named projects Authority tracks publicly are the East Havering Data Centre Campus, where 600 megawatts of capacity has been announced ahead of a long phased build still subject to approval, and the Heathrow Estate Data Centre in Hounslow, approved by committee for a 48 megawatt IT load with operator, detailed design and power delivery still outstanding.
Power, Not Planning, Is Now the Binding Constraint
Authority’s analysis identifies electricity access as the clearest system-wide limit on delivery. City Hall reports approximately 760 megawatts of current peak data centre demand against a connection queue exceeding 8 gigawatts, more than ten times current demand. A separate planning document reviewed in the analysis records 1,289 megawatts of reported secured capacity, where site, permission and power have all been confirmed together.
National Grid’s North West London Upgrade, launched on August 13, 2026, includes a new substation and roughly 260 kilometres of new and upgraded cable, and is intended to unlock new connections including five data centres. Assad Noori, Head of Data Centres for JLL’s Work Dynamics EMEA team, has said publicly that the determining factor for new sites is increasingly where sufficient power can be secured, rather than simply where demand exists.
Approval Is Not the Same as Delivery
The analysis is explicit that a favourable planning decision does not confirm that a project will be built, connected to the grid, or brought into operation. Of the 50 projects Authority monitors, 10 have reached a recorded build-complete stage in planning terms, while none have independently verified operational status. Andrew Eldred, Managing Director of the Electrical Contractors’ Association, has noted that new capacity must be delivered safely and sustainably, with proper regard for local grid capacity, a view Authority’s analysis says is consistent with the gap it observes between planning momentum and confirmed delivery.
Authority’s analysis also points to a broader locational shift. JLL research cited in the report found that European hyperscale data centres due to open within two years now sit an average of 175 kilometres from major urban hubs, compared with 46 kilometres for projects delivered between 2022 and 2025, a pattern Authority says may extend to schemes linked to the London market as land and power constraints push development further afield.
The complete index, monthly historical data and project-level pipeline detail are available on Authority.inc, alongside the platform’s other London planning indexes.
This release is based on Authority Intelligence’s published planning index and pipeline data, current as of the September 2026 edition. The figures describe planning-stage activity only and do not constitute confirmation that any named project will secure financing, grid connection, or operational status. Readers should refer to Authority’s full methodology and underlying public planning sources before relying on these figures for investment or development decisions.
About Authority INC
Authority INC is an industry forecasting and planning intelligence platform that provides data-driven analysis of development activity, project pipelines, and market trends.