EDF expands battery storage portfolio through strategic partnership with BW ESS on 350MW Hams Hall project in North Warwickshire

EDF expands battery storage portfolio through strategic partnership with BW ESS on 350MW Hams Hall project in North Warwickshire

(IN BRIEF) EDF and BW ESS have partnered to develop and optimise the first phase of the Hams Hall Battery Energy Storage System in North Warwickshire, a major grid-scale project with a capacity of 350MW / 1,243MWh. The system will provide EDF’s longest-duration battery to date, capable of supplying electricity for up to 3.5 hours and supporting around 1.3 million homes during peak demand. EDF will optimise the project using its PowerShift platform under a 10-year agreement, helping to balance the grid and integrate more renewable energy. A second phase will expand total capacity to 400MW / 1,424MWh, with commercial operations expected in late 2026. Co-owned with AIP Management, the project will become BW ESS’s largest globally and is strategically located near Birmingham with strong grid connectivity. The initiative highlights the growing importance of battery storage in enhancing energy security and enabling the UK’s transition to a low-carbon electricity system.

(PRESS RELEASE) LONDON, 28-Apr-2026 — /EuropaWire/ — EDF has entered into a strategic partnership with BW ESS to optimise the first phase of the Hams Hall Battery Energy Storage System (BESS) in North Warwickshire, marking a significant step forward in expanding the UK’s grid-scale energy storage capacity.

The project, designed as a 350MW / 1,243MWh battery installation, represents the longest-duration battery asset EDF has contracted to date, with the capability to deliver electricity for up to 3.5 hours. Once operational, the system is expected to support the power needs of approximately 1.3 million homes during periods of peak demand, contributing to a more resilient and flexible electricity network.

Under a 10-year floor agreement, EDF will deploy its PowerShift optimisation platform to manage the system’s performance. This technology will enable the battery to balance supply and demand on the grid, enhance stability, and facilitate the integration of increasing volumes of renewable energy generation across the UK.

Currently under construction on the northeastern outskirts of Birmingham, the Hams Hall project is scheduled to reach commercial operation in the fourth quarter of 2026. While the first phase will deliver 350MW of capacity, a planned second phase will add an additional 50MW, bringing total site capacity to 400MW / 1,424MWh.

Hams Hall is a key component of BW ESS’s growing UK portfolio and is jointly owned with AIP Management. Upon completion, it will become BW ESS’s largest project globally, significantly surpassing the scale of its earlier Bramley BESS development.

The site benefits from its proximity to major electricity demand centres and its connection to the Hams Hall 400kV National Grid substation, enabling efficient access to balancing services while reducing congestion risks within the grid.

The collaboration brings together BW ESS’s experience in developing and operating large-scale energy storage assets with EDF’s expertise in optimisation and market operations. Together, the partners aim to maximise the commercial performance of the project while reinforcing its role as a critical flexibility asset within the UK electricity system.

The Hams Hall development forms part of EDF’s broader strategy to expand its battery storage portfolio and support the increasing role of energy storage in managing intermittent renewable generation such as wind and solar power. As the UK continues to transition toward a low-carbon energy system, projects of this scale are expected to play a central role in maintaining grid reliability and ensuring energy security.