RWE, the largest power producer in Wales, has taken the final investment decision to go ahead with its largest UK storage project, Pembroke Battery Storage. The circa £200m ($266.94m) development, once constructed, is expected to play an important role in the operation of the Pembroke Net Zero Centre decarbonisation hub in South Wales.
The project construction was announced by the First Minister for Wales, Eluned Morgan, at the Wales Investment Summit, underlining the Welsh Government's commitment to attracting major infrastructure investment that will support the nation's clean energy transition.
The project received planning consent in January this year and was also successful in the UK’s latest capacity market auction, securing a critical route to market.
Construction will start in the first half of 2026 (H1 2026), with commissioning and operations expected in H2 2028, subject to receiving an updated grid connection.
The storage system would be located on a 5.1-hectare site south of RWE’s Pembroke power station and will consist of 212 lithium-ion battery containers. Once constructed and fully operational, the 700 megawatt-hour (MWh) battery will be capable of continually discharging up to 350MW-electrical directly to the grid for two hours.
Nikolaus Valerius, CEO of RWE Generation, said: “Our Pembroke battery is our UK flagship storage project and will make an important contribution to stabilising the UK energy market by efficiently storing surplus energy and feeding it into the national grid in a targeted manner when required.”
To operate the plant in harmony with the local ecosystem, part of the Pembroke Battery project will involve implementing biodiversity measures in the areas surrounding the operational power station site, including meadow planting, native woodland and scrub planting, and developing a new large pond to support local wildlife.
RWE currently operates battery storage systems with a total capacity of around 1.2GW in the US, Europe and Australia, has a further 2.7GW under construction and plans to significantly increase its worldwide battery storage capacity.
