The Welsh government has assumed control of a contentious proposal to construct a data centre in Cardiff, removing the decision from the city council and placing it in the hands of a planning inspector and cabinet minister. Developer Curtis Hall seeks to build the 30,292 square-metre facility on land currently occupied by a park and ride facility near Llanrumney in the capital's eastern suburbs, along with permission for gas turbines capable of temporarily powering the site. According to BBC News, Welsh Planning Minister Sian Gwenllian made the decision to call in the application, citing "substantial controversy" as justification for removing it from local authority jurisdiction.
The call-in occurred the evening before Cardiff's planning committee was scheduled to debate the scheme on 12 November, forcing cancellation of that meeting. According to reporting on the decision, a holding direction issued on 24 August had already prevented Cardiff Council from granting permission while ministers deliberated whether to assume control. The application, referenced as 26/00109/HYB, encompasses associated buildings, access works, landscaping and a bridge across the Rhymney River.
The controversy surrounding the scheme reflects broader tensions over data centre development in Wales. Cardiff Council has an agreement to sell the park-and-ride site to Curtis Hall, and the Welsh government is developing its own national policy on data centres, with Planning Minister Gwenllian having stated that such facilities "must be on our terms." The government intends to publish this national data-centre policy before the end of 2026.
What triggered the call-in?
Gwenllian determined that the proposed development raises concerns extending beyond local significance, particularly regarding potential conflicts with national policy on transport, energy and flood risk. In her letter to Cardiff Council, she noted that
"Wide interest in the environmental impact and the policy in relation to data centres means the case has generated substantial controversy beyond the immediate locality."The application attracted petitions bearing approximately 4,000 signatures and formal objections from all Members of the Senedd representing Caerdydd Fynnon Taf.
Opposition has come from multiple quarters. All constituency Members of the Senedd from Plaid Cymru, Labour, Reform and the Green Party, including a Welsh government minister, formally requested the call-in. Labour MP for Cardiff East Jo Stevens had offered "conditional support" contingent on the scheme not compromising local water supplies, though she acknowledged that
"the case for data centres of this type reflects the evidenced demand for digital infrastructure to support the UK's growing technology sector."
What are the main concerns about the development?
Community objections span multiple environmental and social dimensions. Residents and campaigners have raised concerns about the site's climate change impact, the loss of the park and ride service, air quality, lighting, noise, flood risk and water consumption. The proposal to potentially deploy 49.9MW gas turbines for up to five years—until a permanent grid connection becomes available—has drawn particular criticism. Friends of the Earth characterised the temporary power arrangement as "climate-wrecking," though Curtis Hall maintained the turbines would only be deployed as a worst-case scenario if alternative technologies could not be implemented. The developer denied deliberately limiting the plant to 49.9MW to circumvent the 50MW threshold that would require Welsh government planning permission.
The loss of transport access particularly concerns residents. Abi Baxter, secretary of campaigning union Acorn Cardiff, emphasised that
"It was going to replace the Llanrumney Park and Ride - that would have left residents without transport."However, Cardiff Council's planning officers had recommended approval on 6 November, arguing that many impacts could be avoided, mitigated, compensated for or appropriately managed. The council recommended that Curtis Hall enter an agreement to provide an alternative park and ride facility with no fewer than 225 spaces, maintaining that number at the current site until the replacement opens.
What did local politicians say about the decision?
Reactions to the call-in divided along political lines. Plaid Cymru MS Nick Carter, who had requested the call-in, called it the
"right decision and a major step forward for everyone who has fought to protect this community."Many campaigners and politicians had sought the call-in partly because they believed the issue should be determined by national policy rather than by individual councils.
However, Reform MS Cai Parry-Jones objected to the Welsh government's intervention, arguing that
"My constituents are the ones who would live with the loss of the park and ride, or benefit from the investment a data centre might bring. It should be their elected councillors, acting on their behalf, who decide whether this project goes ahead, not the Cardiff Bay lanyardocracy."
What happens next?
Planning and Environment Decisions Wales will now examine the application and prepare a report for the cabinet minister responsible for local government, housing and planning, who will make the final determination. A public inquiry represents one option the planning inspector could pursue, though no timescale for the decision has been announced. Notably, the Welsh government retains the authority to approve the application despite the call-in, meaning the outcome remains uncertain for both supporters and opponents of the scheme.
Abi Baxter acknowledged the ongoing nature of the campaign, stating that
"We don't know what the Welsh government will do, absolutely. But let's hope that they listen to the community."Curtis Hall responded to the call-in by reaffirming its commitment, saying the company remains
"committed to engaging constructively with Welsh government, Cardiff Council and the local community, and hope to realise the opportunities this investment could bring, subject to Welsh government enabling this project to move forward."
