AIP Management and BW ESS form long-term partnership through investment in 2.4GWh UK battery storage portfolio
Copenhagen, 25 September 2025 — AIP Management (“AIP”), a leading investor in energy and decarbonisation infrastructure, has agreed to acquire a 49% equity stake in a UK-based battery energy storage system (“BESS”) portfolio with a total capacity of 700MW and 3.5-hour duration from BW ESS, a global developer, owner and operator of energy storage systems. The transaction marks AIP’s first dedicated investment in standalone battery storage and reflects its strategy of investing alongside industrial partners with complementary expertise.
The portfolio comprises three assets, including Bramley (100MW / 331MWh), which is already operational, and Hams Hall (400MW / 1,422MWh) and Berkswell (200MW / 712MWh) which are under construction. Upon completion, the assets will be held in a newly formed AssetCo, with BW ESS retaining a 51% majority stake. BW ESS will manage construction and operations across the portfolio, drawing on its track record of more than 500MWh of operational BESS, 3.3GWh under construction, and a development pipeline spanning six markets.
The investment is underpinned by strong market fundamentals in the UK, where the growing share of intermittent renewables, declining baseload generation, and rising grid constraints are creating an urgent need for flexible capacity. Large-scale battery storage has become critical to ensuring system stability, managing power price volatility, and supporting the security of supply. Located in the Midlands and South-East of England, the portfolio benefits from proximity to major electricity load centres and National Grid substations, reducing congestion risks while maximising access to arbitrage and balancing services. Once operational, these batteries will be able to support the electricity needs of 2.3 million UK homes for 3.5 hours, providing a substantial contribution to UK energy security. Revenue stability is supported by long-term capacity market contracts and robust offtake arrangements, which provide cash flow visibility and strong downside protection while preserving upside potential.
“This investment reflects our conviction in the UK energy storage market and builds on the knowledge we have developed through our existing investments in co-located BESS,” said Greg Falzon, Partner and Co-Head of Investments at AIP. “We are very pleased to form this partnership with BW ESS, which brings highly complementary industrial expertise and operational capabilities to our investment approach. Together we will deliver long-term value while enabling the deployment of critical flexibility in the UK power system.”
“We are delighted to welcome AIP as our partner in this strategically important portfolio,” said Erik Strømsø, CEO of BW ESS. “We see strong alignment in our approaches and a shared ambition to deliver storage assets at scale. With AIP’s infrastructure expertise and long-term perspective alongside our operational capabilities, we are confident this partnership will support the UK’s energy transition and provide lasting benefits to both parties.”
The acquisition is subject to customary regulatory approvals.
About AIP Management
AIP specialises in decarbonisation and energy infrastructure investments that facilitate the energy transition in Europe and North America. Our team comprises 80 professionals with extensive expertise in investments and energy working from Copenhagen, London, Madrid, and New York. To date, AIP has invested over €8 billion in infrastructure assets. This includes renewable energy assets with a capacity of approximately 7 GW. Once fully operational, AIP’s investments, will contribute to avoiding 10 million tons of greenhouse gasses and support about 6 million households with renewable electricity. AIP is part of Storebrand, a Nordic financial group, which owns 60% of AIP.
To find out more, visit: aipmanagement.dk
For further information, please contact:
Brackendale Consulting
Archie Graves: archie@brackendaleconsulting.com or (+44) 7803 261488
Jack Sheppard: jack@brackendaleconsulting.com or (+44) 7517 778219
About BW ESS
BW ESS is a global energy storage owner-operator, moving with speed to develop and build market-leading energy storage projects across multiple countries. Typically working with local development partners, the business is active in the UK, Australia, Italy, Germany, Spain, and Sweden. It has more than 500MWh of operating BESS projects, with 3.3GWh under construction and a development pipeline of about 9.5GWh. BW ESS has a strategy to hold assets for the long-term, taking a hands-on approach to unlock value throughout the energy storage asset lifecycle. Part of BW Group, BW ESS can leverage a global industry network, as well as decades of experience in energy infrastructure investment, delivery, and operation.
To find out more, visit: https://bw-ess.com/
For further information, please contact:
bwess@tamarindo.global