How clean is the grid behind Hertfordshire Data Centre?

Hertfordshire Data Centre runs on United Kingdom's grid, which was 217 gCO₂/kWh and 64% clean in 2025 (Ember).

Where is Hertfordshire Data Centre located?

Hertfordshire Data Centre is in Welwyn Garden City, Hertfordshire, United Kingdom.

Mapped (unverified)

Hertfordshire Data Centre

Welwyn Garden City, Hertfordshire, United Kingdom

Hertfordshire Data Centre is a mapped data center in Hertfordshire, United Kingdom. DataCentersExposed has documented a 127,877 sq ft footprint and 1 environmental-permit record at this site. It runs on United Kingdom's grid, which was 36% fossil-fuelled at 217 gCO₂e/kWh in 2025 (Ember).

Reporting by Eric Keller · Updated Jun 12, 2026

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Real parent

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Operator

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Est. capacity

~25-55 MW

Footprint

127,877 sq ft

Grid carbon

217 gCO₂/kWh

Clean electricity

64%

Region

Hertfordshire

Attribution & capacity confidence:mediumprimary source

Status · click to filter

Most sites are mapped — located but awaiting a second source. How we verify

Dot size = disclosed capacity (MW). Smallest = undisclosed, not small.

Overview

source: link

Was labelled as HSBC but I believe it's not (entirely) occupied by them any more.

The grid behind this site

source: Ember · Eurostat

Grid carbon intensity

217 gCO₂/kWh

Clean electricity

64%

Fossil electricity

36%

National grid context, not this facility's own metering. Full country picture: United Kingdom data centers.

In the news

source: Google News (local + English)

Environmental permits

source: Permit register

COLT DATA CENTRE SERVICES UK LIMITEDEPR/KP3139DW
EPR permit · holder "COLT DATA CENTRE SERVICES UK LIMITED" · Welwyn Hatfield area of responsibility, after 1 April 2012 · Combustion; Any Fuel =>50MW - 1.1 A(1) a) · within ~2 km of the mapped site