At the former Uskmouth Power Station site in Newport, a new chapter in the UK’s energy story is being written. Once coal-fired, the site is now being transformed into a sustainable energy hub — home to the landmark Afon Wysg Battery Energy Storage System (BESS).
This flagship project at the Uskmouth Sustainable Energy Park demonstrates how underused industrial land can be repurposed into critical infrastructure for a low-carbon future. With planning consent secured in just four months, the development reflects both strong policy alignment and the urgency of the UK’s clean energy transition.
Supporting the UK’s Rapidly Growing BESS Market
Battery energy storage is playing an increasingly vital role in balancing the grid, supporting renewable integration, and enhancing energy security. The UK is one of Europe’s leading BESS markets, with over 5 GW of operational battery storage capacity and a project pipeline exceeding 30 GW as of recent industry reports. As renewable generation expands — particularly wind and solar — flexible storage solutions like BESS are essential to stabilise supply and manage peak demand.
The Afon Wysg project contributes directly to this national effort, delivering 120 MW of battery storage capacity at 132kV — strengthening the resilience of the transmission network in the National Grid Electricity Transmission (NGET) area.
Powersystems: Powering the Transition to a Sustainable Future
As a high-voltage electrical engineering specialist, Powersystems brings technical excellence and added value from the outset. We are at the forefront of the UK’s most progressive urban decarbonisation and battery storage initiatives, supporting the transition to a robust low-carbon economy.
With 20 Battery Energy Storage System (BESS) projects now within our portfolio, we have established ourselves as a trusted delivery partner for large-scale grid integration and Electrical Balance of Plant (EBoP) works across the UK. Our growing track record reflects both market confidence and our capability to deliver complex, high-voltage infrastructure safely, efficiently, and to the highest industry standards.
At Afon Wysg, Powersystems is delivering a complete electrical infrastructure package to integrate:
- 120 MW BESS
- 18 transformers
- 36 Power Conversion Systems (PCS)
- 55 battery containers
- 132 kV grid connection
Engineering Scope: From Grid to Battery
132kV Works – Uskmouth Substation Integration
Powersystems is delivering a comprehensive grid-to-battery connection package, covering high-voltage integration, transformer installation, medium-voltage infrastructure, and advanced control systems.
Works at Uskmouth Substation include 132 kV installation and integration within the existing network, alongside the design and commissioning of a new 132/33 kV grid transformer.
The project also includes full 33 kV cable infrastructure, switchboard installation, fibre optic communications linking SCADA and inverter systems, and associated protection and control systems.
All works are being delivered in line with relevant industry standards to ensure full safety, performance, and compliance.
Repowering a Legacy Site for a Clean Energy Future
The transformation of Uskmouth from a coal-powered station into a centre for renewable and flexible energy infrastructure symbolises the wider shift happening across the UK energy landscape.
By combining existing grid infrastructure with advanced battery storage technology, the Afon Wysg BESS project unlocks the full potential of the site while strengthening national energy resilience.
For Powersystems, this project represents more than technical delivery — it reflects our commitment to powering the transition to a sustainable future through engineering excellence, innovation, and partnership.
Notes to Editors:
Contact Information:
- This article is written by Jules Daly, Marketing and Communications Manager at Powersystems.
- Email jules.daly@powersystemsuk.com Telephone 01454 318000
- Photography Copyright please credit all images used to powersystemsuk.co.uk
Powersystems are powering the transition to a sustainable future
Powersystems: The High Voltage Specialist of Choice
Powersystems is a leading employee-owned high voltage electrical engineering specialist with over 49 years of experience delivering safe, efficient, and high-quality infrastructure solutions across the UK.
As the first Lloyd’s NERS-accredited Independent Connection Provider (ICP), we have been delivering contestable grid connections up to 132 kV for over 29 years. Our trusted expertise spans the full project lifecycle—from design and installation to commissioning—supporting clients across renewable energy, utilities, and industrial sectors.
Since 2000, Powersystems has connected over 10 GW of renewable energy to the UK grid, including onshore and offshore wind, solar, hydro, tidal, and battery energy storage systems (BESS). We’ve also delivered critical infrastructure for electric vehicle charging, CHP, STOR, rotating stabilisers, and private wire networks.
Working in partnership with developers, contractors, and DNOs, we’ve connected 30% of the UK’s onshore wind farms—playing a vital role in the transition to Net Zero by 2050.
Our commitment to safety, sustainability, and innovation is embedded in our ISO-accredited integrated management systems and our ‘Priority No.1’ health and safety culture. We continue to invest in people, technology, and partnerships to remain the high voltage specialist of choice.
As an employee-owned business, Powersystems empowers every team member to contribute to our shared success. Our ownership model fosters a culture of collaboration, accountability, and continuous improvement—ensuring we deliver excellence for our clients, safely and efficiently.