A proposed Cardiff data center may need temporary gas power for up to five years if its grid connection is delayed, as Welsh ministers weigh the project and nearby transport access remains in question.
Curtis Hall Ltd’s application proposes a campus of up to 150 megawatts at Cardiff East Park and Ride. Its documents say a grid connection may not be available until after the data centers are built and brought into use.
The application gives conflicting figures for the temporary energy center’s capacity. The Planning Statement and Environmental Statement Chapter 3 list up to 47 megawatts, while the Air Quality chapter sets a maximum of 49.9 megawatts. The Air Quality chapter lists seven gas turbines, one steam generator and two diesel backup generators; it says six turbines would operate at once and models the center running from July 2028 to July 2033.
The BBC reported that Curtis Hall described the turbines as a worst-case scenario for emissions and noise. It also reported the company had not confirmed the technology and was considering alternatives. Curtis Hall said the temporary plant might not be needed if a grid connection arrives in time, the BBC reported.
A Sept. 7 parliamentary answer cited NESO’s 2025 data showing 72.8 gigawatts of data center capacity allocated in Great Britain’s connection queue. The answer said a count of individual projects was unavailable and that data center connections were contributing to delays for demand projects. Ofgem’s consultation proposed a data center commitment fee and queue-management milestones. It has closed, with a decision pending.
The site currently serves as a park-and-ride, with free buses to University Hospital of Wales. The Guardian reported on Oct. 24 that hospital staff and patients use the service and that more than 1,200 objections had been filed as of that date.
Cardiff East MP Jo Stevens said in a Sept. 4 statement that Cardiff Council could continue processing and consulting on the application but could not grant permission while ministers consider whether to call it in. Stevens said her support for the project depended on a replacement park-and-ride and continued service for hospital staff and patients. She also said an approved project could contribute to funding a third Llanrumney exit onto the A48.
The Planning Statement forecasts up to 125 jobs during operation, up to 505 direct construction jobs and 603 indirect and induced construction jobs per year. The next steps are decisions by Welsh ministers on whether to call in the application and by Ofgem on the connection reforms; neither has a stated decision date.
