BW ESS Lands OCBC, Rabobank and Societe Generale Debt Deal for Hams Hall Battery Site

BW ESS has closed a debt financing agreement for its Hams Hall Battery Energy Storage System in the West Midlands, a project the company says will be Europe's largest operational BESS site by MWh at commercial operations date.

The deal, announced in London on 22 October 2026, brings in OCBC, Rabobank and Societe Generale as international lenders, each providing the facility in equal proportions, with Rabobank additionally serving as Facility Agent. The transaction is expected to complete at the project's Commercial Operations Date.

Scale of the Hams Hall project and its grid role

Sited next to National Grid's Hams Hall substation, the battery facility will initially deliver 350 MW / 1,243 MWh of storage capacity, rising to 400 MW / 1,424 MWh once the second phase is completed.

At full operation, the site will be able to support the electricity needs of approximately 1.3 million homes for up to 3.5 hours, integrating renewable energy, increasing grid resilience and strengthening UK energy security. Revenue for the first phase is underpinned by a 10-year floor and optimisation agreement signed with EDF earlier this year. BW ESS CFO Nick Stamp said Hams Hall will provide critical infrastructure for balancing the UK's increasingly renewable-powered electricity system while enhancing energy security and reliability for consumers.

Lender response and market confidence

The financing was secured through a highly competitive process that drew interest from more than 30 lenders across the global banking community. According to BW ESS, that level of engagement reflects the company's development and operating track record and the growing significance of battery storage in the UK's energy transition. Stamp called the financing another major milestone for the company and the wider UK energy storage market.

"The exceptionally strong response from lenders demonstrates growing confidence in both the investment case for battery storage and BW ESS' ability to develop and operate strategically important infrastructure assets," he said.

What the banks said

Ms Elaine Lam, Head of Global Corporate Banking at OCBC, said the bank was delighted to support BW ESS in the successful financing of the Hams Hall BESS facility, describing it as a landmark project that will become the largest BESS project by MWh in Europe at completion. She said the project will strengthen the resilience and flexibility of the UK power network and supports the energy transition, in which battery storage infrastructure is essential to enable greater integration of renewable energy and maintain grid stability. The transaction, she added, reinforces OCBC's commitment to supporting UK energy and infrastructure investment under its USD 13.4 billion MOU with the UK Government. Gijs Hofman, Executive Director at Rabobank, said the bank was pleased to support the project as Lender, Facility Agent and Hedge provider.

He pointed to the strong lender interest the transaction attracted, which he attributed to the project's scale, strategic location, high-quality counterparties and BW ESS' track record as a leading battery storage developer and operator. "We see battery storage as a fundamental building block of a flexible, reliable and increasingly decarbonised power system," Hofman said. Nathalie Lemarcis, Managing Director at Societe Generale, said the bank was pleased to support BW ESS in this landmark financing for one of Europe's largest battery energy storage projects. She said the transaction highlights battery storage's increasingly important role in enabling the energy transition, strengthening grid resilience and supporting energy security, and reflects the bank's commitment to financing critical infrastructure.

Hams Hall within BW ESS's UK portfolio

Hams Hall sits within BW ESS' 2.6 GWh Ardenham portfolio, which is co-owned with energy and decarbonisation investor AIP Management. In the UK, the company currently operates the 331 MWh Bramley BESS in Hampshire, has 1,243 MWh entering operation through Phase 1 of Hams Hall, and 857 MWh under construction at Berkswell. Beyond these assets, BW ESS holds a broader UK development pipeline spanning multiple gigawatt hours. The financing strengthens BW ESS' relationships with leading international lenders and supports continued growth across its global portfolio, the company said.

Global footprint and pipeline

BW ESS is active in the UK, Australia, Italy, Germany, Spain and Sweden. It operates more than 540 MWh of Battery Energy Storage Systems, has approximately 12 GWh under or pre-construction, and a development pipeline of several gigawatts. The company is part of BW Group and builds on decades of global infrastructure experience.

Advisers to the deal

CMS acted as legal adviser to BW ESS, while WFW advised the lenders. Everoze served as technical adviser and Modo Energy as market adviser to the transaction.