On 18 October the Telegraph reported that Microsoft had pulled out of Nscale's planned AI data centre on Langston Road in Loughton, Essex. Bloomberg, Reuters, the BBC and City AM followed. Microsoft was to be the anchor tenant: Nscale had billed the site as "the UK's largest AI supercomputer", with 23,040 Nvidia GB300 chips due in early 2027. Microsoft says the decision "relates to a single site" and gave no reason. The reason everyone assumes is power. In September the Guardian reported that UK Power Networks, the local distribution company, had told Nscale it could not supply enough electricity until "somewhere between the early and middle 2030s".
Nscale calls it "this unfortunate London-wide grid issue". UKPN, which "would not discuss a single project", said many data centres connecting to its network are "awaiting works on the wider national electricity transmission network".
On Radio 4's Today programme the next morning, Adam Bell, energy partner at PF Global, was blunter: "it is about the grid, full stop." Bell's explanation is that the south-east has the demand while the generation is elsewhere, with gas in the Midlands and wind in Scotland and the North Sea. Getting that power south "means reinforcing connections, and it means doing so at scale". That work is "taking a very, very long time", slowed by a shortage of commissioning engineers and by decisions split across Ofgem, the system operator and the energy department.
He's right. The grid data backs him up, and it also shows there's a bit more to it.