European data centre operators are reporting the tightest capacity market in a decade, as surging artificial intelligence workloads collide with power grid constraints and extended construction timelines. Industry analysts say vacancy rates across the continent’s major hubs have fallen to record lows, with some markets effectively sold out until 2028.
New figures from real estate consultancy JLL show take-up of data centre space across Europe reached 1,120 megawatts in the first half of 2026, up 38 percent on the same period last year. Frankfurt, London, Amsterdam and Paris, the four largest markets, accounted for more than half of all new capacity, yet even combined supply additions failed to keep pace with demand.
“We have reached a point where the constraint is no longer capital or land, but power,” said Dr Eleanor Whitfield, head of digital infrastructure research at the consultancy. “Operators can find sites, but grid connection queues in several European countries now stretch beyond 2029. That is reshaping how the entire industry plans.”
The pressure is most acute in London, where vacancy in the second quarter fell below 3 percent for the first time since records began. Colliers estimates that more than 60 percent of the capital’s existing data centre stock is already pre-let, with hyperscale cloud providers competing directly with sovereign AI projects for remaining space.
Developers are responding with a wave of speculative construction, but lead times have lengthened considerably. Average time from planning permission to operational data centre now stands at 42 months, according to CBRE, up from 28 months in 2021. Grid connection delays account for most of the increase, with energy-intensive facilities competing for the same constrained capacity as housing and industry.
The squeeze has also pushed pricing higher. Average colocation rates in western Europe have risen roughly 19 percent over the past twelve months, with the steepest increases in Dublin and Frankfurt. Some operators have begun signing ten-year leases with built-in escalation clauses, a practice previously confined to the most sought-after locations.
Analysts expect the imbalance to persist well into 2027. The European Commission is consulting on priority grid connections for strategic digital infrastructure, and several member states are streamlining permitting for facilities above 50 megawatts. Industry bodies argue that faster decisions are essential if Europe is to retain AI workloads that might otherwise land in North America or the Middle East.
“The next eighteen months will determine where the next generation of European AI infrastructure is built,” Whitfield added. “The demand is there. The question is whether the planning system can keep up.”