Clock / UK data centres · updated 26 October 2026
In 2024, data centres in the South East used 1,785 GWh (1.79 TWh) of electricity from the grid. That was 5.1% of all grid electricity consumed in the area src.
Gigawatt-hours of grid electricity used by data centres each year, and that use as a share of all grid electricity in the South East. Source: DESNZ src.
| Year | Data centres | GWh | Share of area electricity |
|---|---|---|---|
| 2020 | 59 | 1,139 | 3.2% |
| 2021 | 61 | 1,260 | 3.5% |
| 2022 | 65 | 1,424 | 4.1% |
| 2023 | 68 | 1,568 | 4.5% |
| 2024 | 68 | 1,785 | 5.1% |
Use went from 1,139 GWh in 2020 to 1,785 GWh in 2024, up 57%, while the share of local electricity moved from 3.2% to 5.1%. DESNZ counted 59 operational data centres here in 2020 and 68 in 2024 src. Across Great Britain, data centre use rose 41% over the same period.
The South East used 40.0% of all data centre electricity in Great Britain in 2024 (1,785 of 4,460 GWh). Among the 8 areas DESNZ splits Great Britain into, it ranks 1st for total data centre electricity and 2nd for the share of local electricity going to data centres src. For comparison, data centres used 1.8% of grid electricity across Great Britain as a whole.
1,785 GWh is about the yearly electricity of 714,000 typical UK homes, at Ofgem's 2,500 kWh a year for a medium home src. DESNZ's two figures also imply that all grid users in the South East used about 34,851 GWh in 2024 (data centre use ÷ its share).
Derived: homes = data centre kWh ÷ 2,500 kWh, rounded to 3 significant figures. Implied area total = data centre GWh ÷ share. Share of GB = area GWh ÷ GB data centre GWh.
DESNZ splits this area further src:
OpenStreetMap and Wikidata have 74 data centre sites mapped inside the South East's boundary src src, 69 of them with a name: 4D Data Centers - Gatwick, AWS Bracknell Data Centre, AWS Didcot Data Centre, Ark Data Centres, Ark Data Centres - Longcross Park, Asanti - Farnborough, Asanti - Reading, Bank Of America, CSquare London LHR3, CXD Infrastructure Solutions, CapitaLand Ascendas REIT, Centrilogic, China Mobile Slough, CryrusOne LON4, CryrusOne LON5, CustodianDC DA2, CustodianDC Maidstone, CyrusOne LON3, Datum Farnborough Data Centre, Digital Realty LGW14, Digital Realty LGW15, Digital Realty LGW16, Digital Realty LHR26, EXA Infrastructure - St James House, Elasticity Slough, Equinix LD10, Equinix LD11x, Equinix LD5, Equinix LD6, Equinix LD7, Global Technical Realty London GB One, Goldman Sachs, Gravity Edge LDN1, IBM Horsham, Iron Mountain LON-3, Iron Mountain London LON-1, Keppel Data Centres (Vodafone) - London, Lumen, Microsoft Thames Valley Park Data Centre, NTT Slough 2 and 29 more.
Sites placed by point-in-polygon against ONS local authority boundaries src. Community-mapped sites aren't the same list as DESNZ's count (which only includes colocation and hyperscale data centres with matched meters), so the two numbers differ. OpenStreetMap snapshot: 21 September 2026. Missing one? Add it to OpenStreetMap. See them on the map.
DESNZ's figures cover colocation, managed hosting and hyperscale data centres whose electricity meters could be matched; they exclude enterprise (in-house) data centres and on-site generation, so they're a floor, not a total. Some areas are grouped by DESNZ for disclosure reasons. Download this page's data: local.json.