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The London Compute Ring

Compare power

How large is each proposal’s claimed draw on the grid relative to the others? Circles use true area scale (twice the megawatts looks twice as large). Figures are stated power size on paper, not how much electricity a site will draw day to day.

How to read

Colour = planning status

  • Proposed
  • In planning
  • Approved
  • Building
  • Operating
  • Decommissioned

Outline = size disclosed

  • Solid: megawatts published (area ∝ MW)
  • Dashed: megawatts unknown; sized by site area

Grey demos are style only, not a status colour.

Stated size disclosed (by megawatts)

Sorted by each site’s published power size: biggest size stated for that site if recorded, otherwise grid connection applied for, otherwise first stage only. Equal megawatt figures share a rank (joint largest) and are listed A-Z. Circle area matches megawatts; colour is status, same as the map.

  1. 1Digital Reef 'London Data Freeport' (East Havering)proposed600 MW · biggest size stated for this site
  2. 2Equinix Hertfordshire Campus (South Mimms)proposed (reported consented)250 MW · biggest size stated for this site
  3. 3Ada Infrastructure Docklands campusproposed (reported under construction)210 MW · biggest size stated for this site
  4. 4Ark Elstree campus (former Mercure Hotel)proposed200 MW · biggest size stated for this site
  5. 5CorScale Iver (Court Lane)approved103 MW · biggest size stated for this site
  6. 6Yondr London campus (Slough)operating100 MW · biggest size stated for this site
  7. 7Colt DCS Hayes Digital Park (expansion)proposed (reported consented)97 MW · biggest size stated for this site
  8. 8Abbots Langley data centre (Bedmond Road)approved96 MW · biggest size stated for this site
  9. 9CyrusOne LON6 (Iver Heath)proposed (reported consented)90 MW · biggest size stated for this site
  10. 10Manor Farm data centre (Poyle Road)approved72 MW · biggest size stated for this site
  11. 11Pure DC Brent Cross (LON01, Building 2)proposed (reported under construction)70 MW · IT equipment only
  12. 12Colt DCS Hayes Digital Park (existing campus)operating63 MW · biggest size stated for this site
  13. 13Pure DC / SEGRO Premier Park (Park Royal)proposed (reported consented)56 MW · biggest size stated for this site
  14. 14Vantage London I (LHR1, PowerGate)operating55 MW · biggest size stated for this site
  15. 15Global Switch London Eastoperating45 MW · biggest size stated for this site
  16. 16GTR GB One (Slough)operating40.5 MW · biggest size stated for this site
  17. 17Global Switch London Southproposed (reported consented)40 MW · biggest size stated for this site
  18. 18Kao Data KLON-04 (Harlow)proposed36 MW · biggest size stated for this site
  19. 19Telehouse West Two (Docklands)proposed (reported under construction)33 MW · biggest size stated for this site
  20. 20VIRTUS LONDON19 (Slough)operating32.5 MW · biggest size stated for this site
  21. 21NTT London 1 (Dagenham)operating32 MW · first stage only
  22. 22Equinix LD14 (Slough)proposed (reported under construction)30 MW · biggest size stated for this site
  23. 23VIRTUS LONDON7 (Stockley Park)operating28 MW · biggest size stated for this site
  24. 24=Iron Mountain LON-2 (Slough)operating27 MW · biggest size stated for this site
  25. 24=VIRTUS LONDON4 (Slough)operating27 MW · biggest size stated for this site
  26. 26=Equinix LD5 (Slough)operating25 MW · biggest size stated for this site
  27. 26=Iron Mountain LON-3 (Slough)proposed (reported under construction)25 MW · biggest size stated for this site
  28. 28=VIRTUS LONDON5 (Stockley Park)operating24 MW · biggest size stated for this site
  29. 28=VIRTUS LONDON9 (Slough)operating24 MW · biggest size stated for this site
  30. 30VIRTUS LONDON14 (Stockley Park)operating22 MW · biggest size stated for this site
  31. 31VIRTUS LONDON12 (Slough)operating21 MW · biggest size stated for this site
  32. 32=NTT Hemel Hempstead 3 (HH3)operating20 MW · biggest size stated for this site
  33. 32=Pure DC Brent Cross (LON01, Building 1)operating20 MW · IT equipment only
  34. 32=Vantage London II (LHR2, Park Royal)operating20 MW · biggest size stated for this site
  35. 35=CyrusOne LON4 (Slough)operating18 MW · biggest size stated for this site
  36. 35=CyrusOne LON5 (Slough)operating18 MW · biggest size stated for this site
  37. 35=Digital Realty LGW15 (Crawley Unit 1)operating18 MW · biggest size stated for this site
  38. 35=Global Switch London Northoperating18 MW · biggest size stated for this site
  39. 35=Telehouse South (Blackwall Yard)operating18 MW · biggest size stated for this site
  40. 35=VIRTUS LONDON8 (Stockley Park)operating18 MW · biggest size stated for this site
  41. 41Kao Data KLON-03 (Harlow)proposed (reported under construction)17.6 MW · biggest size stated for this site
  42. 42=Digital Realty LGW16 (Crawley Unit 2)operating16 MW · biggest size stated for this site
  43. 42=Equinix LD4 (Slough)operating16 MW · biggest size stated for this site
  44. 42=Equinix LD6 (Slough)operating16 MW · biggest size stated for this site
  45. 42=Telehouse North Two (Docklands)operating16 MW · biggest size stated for this site
  46. 42=VIRTUS LONDON6 (Stockley Park)operating16 MW · biggest size stated for this site
  47. 47CyrusOne LON2 (West Drayton)operating13.9 MW · biggest size stated for this site
  48. 48VIRTUS LONDON11 (Slough)operating13 MW · biggest size stated for this site
  49. 49NTT Hemel Hempstead 4 (HH4)operating12 MW · biggest size stated for this site
  50. 50=Serverfarm LON1 (Feltham)operating11.4 MW · biggest size stated for this site
  51. 50=VIRTUS LONDON2 (Hayes)operating11.4 MW · biggest size stated for this site
  52. 52=CyrusOne LON3 (Slough)operating9 MW · biggest size stated for this site
  53. 52=Equinix LD10 (Slough)operating9 MW · biggest size stated for this site
  54. 52=Equinix LD13x (Slough)operating9 MW · biggest size stated for this site
  55. 55=Kao Data KLON-01 (Harlow)operating8.8 MW · biggest size stated for this site
  56. 55=Kao Data KLON-02 (Harlow)operating8.8 MW · biggest size stated for this site
  57. 57CyrusOne LON1 (Slough)operating8.7 MW · biggest size stated for this site
  58. 58Iron Mountain LON-1 (Slough)operating8.7 MW · biggest size stated for this site
  59. 59Digital Realty LON1 (Hanbury Street)operating8 MW · biggest size stated for this site
  60. 60VIRTUS LONDON3 (Slough)operating7.2 MW · biggest size stated for this site
  61. 61VIRTUS LONDON10 (Slough)operating6.6 MW · biggest size stated for this site
  62. 62NTT Hemel Hempstead 2 (HH2)operating6.2 MW · biggest size stated for this site
  63. 63VIRTUS LONDON1 (Enfield)operating4.2 MW · biggest size stated for this site
  64. 64Truman Brewery data centre (Grey Eagle Street)approved4 MW · biggest size stated for this site
  65. 65NTT Slough 3 (SL3)operating2.7 MW · biggest size stated for this site
  66. 66Digital Realty Oliver's Yard (LHR18)operating2.3 MW · biggest size stated for this site
  67. 67NTT Hemel Hempstead 1 (HH1)operating2 MW · biggest size stated for this site
  68. 68NTT Slough 2 (SL2)operating1.8 MW · biggest size stated for this site
  69. 69Pulsant Croydon LN-1operating1.4 MW · biggest size stated for this site
  70. 70Netwise London Central (Bermondsey)decommissioned0.5 MW · biggest size stated for this site

Megawatts not disclosed

These sites have no public megawatt figure. Dashed circles use site area when known; if area is also unknown, the marker is location only. Do not read them as size against the list above.