Electrical equipment installed at SSE's 150MW Fiddler's Ferry battery site in Cheshire

RSK Group has reported the installation of key electrical equipment at the Fiddler's Ferry battery energy storage system (BESS) in Cheshire, where SSE Renewables is building a 150MW/300MWh scheme on the site of a former coal-fired power station.

RSK said the installation marked a milestone for the project. SSE Renewables' project page describes Fiddler's Ferry as under construction near Warrington, Cheshire, with work having started in early 2024.

SSE Renewables announced in March 2024 that OCU Energy would be principal contractor and that Fluence had been selected to supply the battery-based energy storage system. OCU Group's own case study describes its scope as the balance of plant works.

Vince Bowler, COO of OCU Energy, said at the time of the appointment: "We're proud to be delivering this contract for SSE Renewables and provide valuable energy storage in the northwest."

The scope

According to OCU Group, its works include a new 275kV National Grid connection and a 140/180MVA 275/33kV main transformer. OCU said the project remains on course to achieve its key National Grid outage, commissioning and energisation milestones, though it gave no dates for them.

SSE Renewables' project page and releases do not give an operational date.

Brian Perusse, Managing Director of Fluence Energy UK, Ltd, said in March 2024: "Fluence is committed to delivering safe and reliable energy storage systems that advance the energy transition."

The sources differ on the location. RSK and SSE Renewables place the project at Warrington, while OCU Group's case study gives it as Widnes, Cheshire.

Background

SSE Renewables took a final investment decision to start construction of the project, announced on 20 December 2023. Richard Cave-Bigley, Director of Solar & Battery at SSE Renewables, said then that the project was its 150MW Fiddler's Ferry BESS in Warrington.

SSE Renewables said the scheme can use the existing grid connection already in place at the former power station. Final demolition of the station's cooling towers was completed in 2023, according to the project page.

The company said the power reserve will support security of electricity supply, maintain grid stability and enable more renewable electricity to connect to the UK grid.

SSE's battery fleet

On 20 March 2026, SSE announced that its Ferrybridge BESS had entered full operation on the site of the former 2GW Ferrybridge power station, which was decommissioned in 2016. SSE said the Ferrybridge project took its operational battery fleet capacity to 200MW/400MWh.

SSE said at that point it had a further 470MW/940MWh of battery storage under construction, including the 150MW/300MWh Fiddler's Ferry BESS in Cheshire.