South Wales Metro Electrification Milestone: Rhymney Line Energized
The South Wales Metro project energizes the Rhymney line, a key electrification milestone. Modernizing the railway with new electric trains enhances capacity and connectivity.

Here’s the combined text with the “Old Article” inserted before the last paragraph, and the cleanup of any residual HTML:
“`html
The South Wales Metro project has achieved a significant milestone with the successful energization of overhead wires along the Rhymney railway line this past weekend. This development closely follows the official opening of the new South Wales Metro depot at Taff’s Well by His Majesty King Charles, marking substantial progress in transforming public transport across the region.
| Key Entity | Critical Detail |
|---|---|
| Project | South Wales Metro |
| Core Action | Energization of overhead wires on Rhymney line; Official opening of Taff’s Well depot. |
| Budget/Value | Over £1bn investment |
| Date/Timeline | Overhead wires switched on weekend of 2025-11-23; Taff’s Well depot opened recently; Rhymney, Treherbert, Aberdare, Merthyr, Coryton and Caerphilly lines electrified since 2023; Cardiff Bay line electrification planned for early 2026; Tram-trains (Class 756) introduced from 2026; Tram-trains (Class 398) introduced next year. |
The energization of the Rhymney line’s overhead wires represents a critical step in the ongoing electrification of the Core Valley Lines, a network that has seen extensive upgrades since 2023. This initiative, often referred to as the ‘Welsh Tube’, aims to bring modern electric train services and fully electric tram-trains to the South Wales Valleys, enhancing capacity and frequency for passengers. The project’s success is underscored by the fact that over 90 per cent of trains on the Core Valley Lines ran to time (within 3 minutes) in October 2025.
Strategic Impact and Future Connectivity
Ken Skates, Cabinet Secretary for Transport and North Wales, highlighted the project’s broader economic and social benefits, stating, “Our investment of more than £1bn to deliver a metro system fit for the future has reached another significant milestone. Electrification of our core valleys lines is helping to create better access to jobs, healthcare, and education with brand new trains offering a faster, more reliable, greener and more accessible transport system.” This sentiment was echoed by Julie James, Counsel General and Minister for Delivery in the Welsh Government, who described the development as a “game changer for many valleys communities, improving connectivity and making it easier for people to get to where they need to go quicker and without any hassle.”
Operational Advancements and Technical Milestones
Dan Tipper, Chief Infrastructure Officer at Transport for Wales, detailed the intensive work undertaken by infrastructure teams. “The electrification of the Upper Rhymney railway line signifies another major milestone for the South Wales Metro and delivering real change for the people of South Wales,” he commented. He further elaborated on the infrastructure achievements: “Our infrastructure teams have worked intensively for the past eight months installing 903 steel structures, supporting 33km of overhead wires and laying 30km of high-voltage cable. This is a huge achievement for our teams, who have worked throughout the day and night to deliver these improvements.” These advancements pave the way for the introduction of new rolling stock, including the Class 756 tri-mode trains on services between Caerphilly and Rhymney from 2026, and the Class 398 tram-trains, which will be introduced next year.
Industry Context
The successful electrification and subsequent introduction of new rolling stock on the South Wales Metro project are indicative of a broader trend within the global railway industry towards decarbonization and the enhancement of passenger capacity and service reliability. For railway operators and infrastructure providers, this project serves as a compelling case study for large-scale urban and regional rail modernization, demonstrating the tangible benefits of significant investment in electric traction and modern rolling stock. The continued rollout of electric services and advanced tram-trains positions South Wales as a leader in sustainable and efficient public transportation, offering valuable insights for similar projects worldwide aiming to improve connectivity and reduce environmental impact.

