National Grid is inviting communities to have their say on plans for a major new substation development at Aberthaw that will help connect renewable energy, battery storage and a data centre to the electricity network.
The proposals would see two new substations built on land next to National Grid’s existing infrastructure at Aberthaw, replacing equipment dating back to the 1950s with a modern facility known as Gileston substation.
The project forms part of National Grid’s wider £3.2 billion investment in the electricity transmission network across Wales over the next five years.
The investment is intended to meet growing electricity demand while supporting the transition towards cleaner energy.
Located alongside the former Aberthaw Power Station, the proposed development would mark a significant change for a site historically associated with coal-fired power generation.
National Grid says the new infrastructure would help create a cleaner and more flexible energy system in South Wales.
The substations are being proposed following requests from developers seeking connections to the transmission network in the region.
These include solar generation, battery storage and data centre developments.
As the owner of the electricity transmission network in England and Wales, National Grid has a legal obligation to facilitate connections to the network.
Electricity demand in the region is also increasing, with the investment intended to strengthen the resilience of the network and prepare it for future growth across South Wales.
This includes potential opportunities linked to the region’s AI Growth Zone.
Matthew Cumming, development director at National Grid, said:
“As South Wales’ electricity needs continue to grow, we need to upgrade the network to connect new renewable energy, storage and demand. Our proposals will help transform a site once associated with coal-fired power generation into infrastructure that supports a cleaner energy future and the region’s continued growth. We encourage local people to come along, learn more about the plans and share their views.”
Residents, businesses and community organisations will have an opportunity to find out more about the proposals at a drop-in information event next month.
The event will take place at The Gathering Place in St Athan from 2.30pm to 7pm on Tuesday 6 October 2026.
Visitors will be able to view the emerging proposals, speak directly with members of the project team and provide feedback on the plans.
An online webinar will also be held on Thursday 8 October for people who are unable to attend the event in person.
