Questions Before ConcreteData centres in England and Wales
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The issues · Power and the grid

Power: who pays, and who waits?

Data centres run day and night, and AI is making them hungrier. They share the grid with your home, your surgery and local businesses, and someone has to pay for the upgrades.

Why it matters

Grid capacity reserved for a data centre is capacity not available for new homes, heat pumps, electric cars or new renewable energy waiting to connect.

These choices are made when a grid connection is agreed, usually long before a planning application appears.

Key points

  • Data centres used about 2% of Great Britain's grid electricity in 2024, mostly in London and the South East.[1]
  • The Government's own demand forecasts do not separate out data centres.[2]
  • The Energy Secretary has called future data-centre demand 'inherently uncertain'.[3]
  • Campaigners told Parliament that the UK's latest carbon budget does not mention data centres at all.[4]
  • Nearly all the electricity a data centre uses ends up as heat. Natural Resources Wales has long expected power stations and incinerators to be sited where their heat can be used; nothing similar is asked of data centres.[5]
  • Germany requires new data centres to plan to reuse at least 15% of their waste heat from July 2026, and the EU requires larger ones to use it where feasible. We have found no equivalent rule in Wales.[6][7]
  • The Cardiff East application is for a 150 MW data centre with a 47 MW temporary energy centre, but its Planning Statement says nothing about using the waste heat. Its environmental assessment rests on a 2022 scoping opinion given for ordinary commercial units.[8][9]

Questions you can ask

Drafted in full so you can copy, adapt and send them. See the questions tracker for all of them, with a downloadable version.

Ask: the local planning authority (planning officer for the application)

“Please confirm the maximum electrical capacity, in megawatts, this development will draw from the grid; whether a grid connection offer has been accepted; what reinforcement works (substations, lines or cables) the connection depends on; and who will pay for them.”

Follow-up: If not answered on the planning file, request the information under the Environmental Information Regulations via WhatDoTheyKnow, then put it to the network operator and Ofgem.

Ask: the Welsh Government Cabinet Minister for Enterprise, Connectivity and Energy (in England, the Secretary of State for Energy Security and Net Zero)

“Does the capital investment announced for data centres in Wales include the cost of the grid and transmission upgrades needed to serve them? If not, who will bear that cost, and what assessment has been made of its effect on other priorities, such as connecting renewable generation and new homes?”

Follow-up: Not yet asked, so far as we know. A freedom of information request via WhatDoTheyKnow to the Welsh Government for any assessment of grid-reinforcement costs linked to the South Wales AI Growth Zone would be a useful parallel step.

6 more question(s) on the in-depth page.

What you can do

  • Find the application on your council's planning website, and check what the documents say on this issue, or whether they are silent. See Start here.
  • Send the questions on this page in writing and keep copies.
  • If information is missing, ask for it through WhatDoTheyKnow.
  • Ask your town or community council to raise the issue in its response.
  • List your group in the campaigns directory so others can find you.

Read this issue in depth

Sources

  1. Department for Energy Security and Net Zero, Data Centre Electricity Consumption in Great Britain, 2020–2024 (Official Statistics in Development, June 2026). https://assets.publishing.service.gov.uk/media/6a3e9f25da47783d87723bf2/Data_centre_electricity_consumption_in_Great_Britain__2020_to_2024.pdf
  2. UK Parliament, Written Question 127433, Dame Chi Onwurah to the Secretary of State for Energy Security and Net Zero, answered by Michael Shanks MP (24 April 2026). https://questions-statements.parliament.uk/written-questions/detail/2026-04-15/127433
  3. House of Commons Environmental Audit Committee, MPs to Examine Data Centres' Climate Impact as Miliband Says Future Demand 'Inherently Uncertain' (February 2026). https://committees.parliament.uk/committee/62/environmental-audit-committee/news/212132/mps-to-examine-data-centres-climate-impact-as-miliband-says-future-demand-inherently-uncertain/
  4. House of Commons Environmental Audit Committee, written evidence: data centres and the Seventh Carbon Budget (2026), noting the omission of disaggregated data-centre demand from the Climate Change Committee's carbon budget projections. https://committees.parliament.uk/writtenevidence/151599/html/
  5. Natural Resources Wales, 'CHP-Ready Guidance for Combustion and Energy from Waste Power Plants' (version 2, September 2014). https://naturalresourceswales.gov.uk/media/2100/chp-ready-guidance-for-combustion-and-energy-from-waste-power-plants.pdf
  6. Directive (EU) 2023/1791 on energy efficiency (recast), Article 26(6); for a summary, see Covington & Burling, 'The EU's Energy Efficiency Directive and its impact on datacenters' (2025). ; https://eur-lex.europa.eu/eli/dir/2023/1791/oj/eng
  7. Kristin Weiß, 'From EU Framework to National Action: How Germany Regulates Data Center Energy Use', Sabin Center for Climate Change Law, Columbia Law School (24 October 2025), on section 11 of the Energy Efficiency Act (EnEfG). https://blogs.law.columbia.edu/climatechange/2025/10/24/from-eu-framework-to-national-action-how-germany-regulates-data-center-energy-use/
  8. Iceni Projects for Curtis Hall Limited, 'Planning Statement: Cardiff Park and Ride East, Pentwyn' (January 2026), paragraphs 2.6, 2.12, 4.22-4.24, 5.6-5.8, 6.36-6.44 and 6.85, application 26/00109/HYB, Cardiff Council planning register. https://www.cardiffidoxcloud.wales/publicaccess/applicationDetails.do?keyVal=T8YL3PECJ8T00&activeTab=summary
  9. Cardiff Council, Screening and Scoping Opinion, reference SC/21/00018/MJR, Cardiff East Park and Ride (2022), reproduced as Environmental Statement Volume II, Appendix 1.2, application 26/00109/HYB. https://www.cardiffidoxcloud.wales/publicaccess/applicationDetails.do?keyVal=T8YL3PECJ8T00&activeTab=documents