Eelpower Energy, the UK grid-scale battery storage platform backed by Equitix, Aware Super and the National Wealth Fund, has completed its fifth asset acquisition: the purchase of the 50MW/200MWh Silkstead battery energy storage project near Winchester from Balanced Grid Works.
The Silkstead battery energy storage system (BESS) is located to the south-east of the Winchester substation and will commence construction in 2027, with commercial operations expected to start in 2028. As Eelpower Energy’s fifth acquisition since its launch in September 2025, Silkstead marks another important milestone in the build-out of its portfolio of grid-scale, flexible storage assets and a step forward in its plans to invest £500m into BESS in Great Britain. Eelpower Energy is aiming to build, own and operate over 1GW of grid-scale battery assets in the coming years with a view to being a leading owner-operator of flexibility on the GB electricity system.
Mark Simon, Chief Executive of Eelpower Energy said, “Silkstead is an important acquisition for Eelpower Energy and a strong addition to our growing battery storage portfolio. This acquisition demonstrates our ability to originate and execute attractive opportunities with high-quality counterparties such as Balanced Grid Works, in order to deliver on the commitment of Equitix, Aware Super and the National Wealth Fund to invest in the infrastructure needed for a cleaner, more flexible and more resilient electricity system in Great Britain.”
Kevin Parr, Director of Balanced Grid Works said, “We developed an excellent working relationship with the entire Eelpower Energy team. This approach enabled us to deal with and address any issues that arose during the due diligence and sale completion process in a timely and equitable manner. We look forward to watching Eelpower Energy move the Silkstead project to the next stage of its development”.



