Access to power, the new bottleneck for data centers

The French paradox: plenty of electricity, few connections

France has abundant and largely low-carbon electricity. In 2025, it exported a record volume of electricity to its neighbours. This is in fact one of the main arguments for attracting data centers.

But producing electricity is not enough: it has to be delivered to the site. An AI campus of several hundred megawatts must be connected to the extra-high-voltage transmission grid, with a dedicated substation and sometimes new lines. These assets require studies, permits and works that take years. RTE, the French transmission system operator, mentions high-voltage connection lead times of two to seven years depending on the area.

A queue that is exploding

RTE's figures show the scale of the phenomenon. At the end of 2024, some forty data center projects represented around 5 GW of signed connection requests. In May 2026, there were around 80 projects and close to 18 GW reserved. The total capacity sought by the sector reaches around 28.6 GW, only part of which is backed by firm commitments.

At the same time, only eight data centers were connected to the high-voltage grid, for a combined 800 MW. More broadly, close to 33 GW of industrial projects across all sectors were waiting for a high-voltage grid connection in July 2026, with data centers accounting for the largest share.

In Île-de-France, the capacity requested by data centers is already approaching the average power consumed by the whole region. This is what is pushing projects towards Hauts-de-France, the Rhône valley or port areas.

Fast track: connecting a gigawatt in three to four years

To avoid losing the largest projects, RTE has set up an accelerated connection procedure, which came out of the AI Summit of February 2025 and was approved by the French Energy Regulatory Commission (CRE). Five sites have been identified, two in Île-de-France and three in Hauts-de-France, each able to host 700 MW to 1 GW within three to four years. The first contract was signed in January 2026 with the Fouju AI campus, for a ramp-up to 1,400 MW.

RTE is also prioritising grid reinforcement in the large industrial port areas (Dunkirk, Le Havre, Fos-sur-Mer) and five intermediate industrial zones, including the south of Île-de-France and Valenciennes-Maubeuge.

Reserving is not consuming

One point is often misunderstood: reserved capacity is not consumed capacity. Operators install servers gradually, as their customers arrive. According to the main operators, it would take ten to fifteen years to reach around 80% of the consumption matching the capacity requested. RTE also observes that data centers connected in recent years use on average only around 20% of their reserved capacity.

The consequence: reserving "generously" ties up grid capacity that could serve other projects, industrial ones in particular. This is one of the ongoing debates about allocation rules.

What this changes on the ground

For a project owner, grid connection is no longer a formality at the end of the project: it is the first question to ask, even before land. It shapes the choice of site, the phasing of works and the commissioning schedule. On the engineering side, it calls for specific skills: high-voltage substations, medium-voltage distribution, grid studies, coordination with RTE and Enedis, and management of the interfaces between the substation and the building.