A review of the European BESS market reveals that the United Kingdom is a leading country in this sector. With one of the largest portfolios at 6.8 GW/10.5 GWh, the UK is also one of the most attractive countries for BESS projects. This development is supported by robust government policies and a diverse range of revenue streams. At the heart of this government support is the Clean Power 2030 Action Plan, which aims to produce as much clean power as the UK consumes by 2030. Battery storage capacity plays a crucial role in securing grid stability in this plan. For this reason, the UK plans to have a BESS capacity of 25 GW by 2030. Achieving these goals seems possible. More than 1.4 GW were commissioned this year alone, and approximately 6.5 GW of capacity is currently under construction. To provide an overview of the sector as a whole and help its participants identify the most important battery storage investors and developers, we have created a list of the world’s largest battery storage investors and a list of the largest battery storage developers in the world.
The British revenue stack for BESS
To maintain the positive development, investors and developers need to have confidence in the return on their investments. One of the measures taken is shifting from relying on frequency services to using energy arbitrage and the Balancing Mechanism. Energy arbitrage, buying electricity when prices are low and selling when they are high, has become increasingly profitable as renewable energy capacities grow. Energy arbitrage is currently the most important source of revenue on the wholesale market, and this is expected to continue. Another reason for the increase in energy arbitrage is the change in the balancing mechanism policy. In the UK, battery energy storage system (BESS) operators can submit bids and offers to charge or discharge their batteries based on system requirements. If accepted, they receive a premium price compared to the wholesale market. Reforms to the Open Balancing Platform have increased battery participation and broadened the potential revenues for battery storage owners. Thanks to the changes, more BESS are taken into account for these services. Conversely, revenues from frequency services are facing a sharp decrease due to market saturation. This is mainly due to increased competition, thanks to the increased installation of BESS projects in the UK. Another stable source of revenue can come from capacity markets. These include services such as voltage control, stability, and restoration. These are offered by the National Energy System Operator in the form of long-term tenders. However, this revenue stream has played a minor role so far because the necessary tasks are usually provided by large thermal power plants. Finally, the Capacity Market aims to ensure that enough reliable generation and storage is available to meet peak electricity demand. Winning bids guarantee a fixed annual payment per MW of available capacity. However, the prices of capacity market contracts have varied significantly in recent years.
Investment activities in the British BESS market in 2025
Given the variety of revenue opportunities for BESS projects and the British government’s active support for the development of battery storage, it’s no surprise that investors are keen to invest in the British energy storage sector. In our transaction database, we record the most significant renewable energy deals. As you can see there is a lot of movement in the British BESS market. So far, we have identified sixteen deals in the battery storage sector for 2025. The number and scale of these deals highlight the success of the policy changes made by the British government to make the BESS market in the United Kingdom attractive to investors.
We will present some of these in more detail below.
Eku Energy acquires Bluestone Energy’s 1 GW / 2 GWh UK BESS portfolio
Eku Energy made the biggest acquisition this year, buying Bluestone Energy’s 1 GW/2 GWh UK battery energy storage system (BESS) portfolio, which includes projects in Surrey, Dorset, East Sussex and Kent. This acquisition positions Eku Energy at the heart of the UK’s energy transition, particularly in the battery storage sector. From its offices in London, Australia and Japan, Eku Energy operates not only in the UK but in five markets. In the UK Eku Energy has several more projects. While the Basildon BESS (28 MW/56 MWh), the Loudwater BESS (40 MW/55 MWh) and the Meldon BESS (40 MW/40 MWh) are already operational, their biggest UK project, the Ocker Hill BESS with a storage capacity of 99 MW/198 MWh.
Statera Energy aquires 680 MW Carrington battery storage project in Greater Manchester
Statera Energy acquired the 680 MW Carrington battery storage project in Greater Manchester at the beginning of this year. Upon completion in 2026, it will be one of the largest battery energy storage systems (BESS) projects in Europe. Statera Energy’s battery storage portfolio is one of the largest in the UK. This comprises 600 MW of completed projects, with a further 3 GW in development.
Zenobe expands BESS portfolio with 400 MW Low Harker battery storage project in Carlisle
Zenobe, a major player in the British battery energy storage system (BESS) market, acquired the 400 MW Low Harker battery storage project in Carlisle, UK, from Innova. The project is scheduled for grid connection in 2028. The company already has contracted storage assets of over 1,100 MW with a huge development pipeline, aiming to deliver 1.2 GW of battery power by 2027. This year, they also announced that their largest battery site in Europe, located in Blackhillock, Scotland, had begun commercial operations. The project has an initial capacity of 200 MW, set to increase to 300 MW/600 MWh by 2026.
AIP Management makes several large battery storage acquisitions
Furthermore, AIP Management has acquired a 49% stake in a 700 MW/2.4 GWh UK battery energy storage portfolio from BW ESS. This three-site portfolio, located in the Midlands and south-east England, strengthens AIP’s position in energy storage investments. AIP Management was also involved in another significant BESS acquisition, purchasing a 50% stake in the 500 MW Coalburn 2 battery storage project in South Lanarkshire, Scotland, from Copenhagen Infrastructure.
Source: Rabobank
Picture Source: Sungrow EMEA, via Unsplash
