Inside Green Mountain’s Romford Data Centre: Built for AI, Powered by Purpose

From critical national infrastructure to community engagement, Green Mountain’s Romford site reflects a new model for AI-era data centres: flexible, efficient, and quietly human.

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Walking through the partially built expansion of Green Mountain’s LON-East facility in Romford, hard hats on and steel-toe-capped boots scuffing across concrete, it is difficult not to acknowledge the scale and precision of what is taking shape. The walls may still be going up, but the capability beneath the surface is already astonishing. Quite literally beneath our feet, vast tanks of fuel sit buried under the tarmac, supporting a network of systems critical to clients that help keep the UK running.

This is not just a data centre. It is part of the digital nervous system of the nation.

Power and Purpose in the East

For decades, London’s Docklands has been one of the nation’s infrastructure hubs. But as Simon Blackburn, Green Mountain’s UK Managing Director, made clear during our visit, “Power is gold dust west of the M25.” The land is tight, the grid even tighter, and meaningful expansion is a logistical and political challenge.

Romford, on the other hand, offers room to grow. The site currently delivers 7MW of live capacity, with 13.6MW more coming online by Q4 2025, and another 16MW ready for bespoke build-to-suit solutions. It is supplied via two independent renewable power feeds and engineered with high-density, AI-ready workloads in mind.

As we know, AI changes everything and “new chips = new tech to cool”, as my scribbled notes put it. This urgency is shaping data centre design almost universally.

At Romford, air cooling is standard, but liquid-to-liquid and direct liquid options are pre-integrated, offering the flexibility that future AI deployments demand.

Cool, Quiet, and Community-Focused

Green Mountain’s Nordic heritage is everywhere in the site’s design philosophy: modular, efficient, sustainable, quiet. The facility reuses the existing building envelope, achieves BREEAM Excellent status, and runs generators on hydrotreated vegetable oil (HVO). LED lighting, 97.5% UPS efficiency, and plans for heat reuse further reinforce its commitment to green operations.

However, what stood out the most during my tour of the facility was not the sustainability as listed on a spec sheet, but sustainability with empathy. From local newsletters keeping local residents informed of the progress of the build, to £30,000 ($39,853) in donations to Romford causes, Green Mountain has made community engagement part of the build and beyond.

Beyond Romford: the Nordics, and the Future Grid

As we toured the site, conversations turned to the national grid, the constraints it faces, and how geography shapes opportunity. With no grid upgrades expected until 2029-2030, power is no longer guaranteed for parts of West London.

Meanwhile, Blackburn pointed out Green Mountain’s wider ambition, to actively seek additional sites elsewhere in the UK which have the opportunity to complement existing sites in the Nordics.

Romford is not just a local site; it is a strategic foothold carving out its own space for growth. With extensive connectivity, proximity to Docklands and Slough, and support from partners like CBRE (operations) and TClarke (construction), the site is positioned to serve hyperscalers, fintech giants, and AI workloads alike, with room to scale and the mindset to do it responsibly.

A New Kind of Infrastructure

The biggest takeaway from the Green Mountain LON-East data centre site visit was not the MW count or the cooling technology that is so readily covered and, rightly, celebrated. It was the shift in tone. Romford feels like the beginning of a new kind of data centre: engineered for AI, yes, but also for trust, transparency, and community.

It is a facility that handles critical financial transactions, sends newsletters to its neighbours, and prepares for workloads we have not even imagined yet.

And when the fuel is buried under the tarmac and the cooling is quiet, you realise: the most important infrastructure is often the infrastructure we never notice.