Farrans starts 857MWh Berkswell battery construction

Farrans has started construction of the Berkswell Battery Energy Storage System near Solihull, putting a 200MW/857MWh transmission-connected storage project into active site delivery.

Early works are progressing across the West Midlands site for client BW ESS, with bulk earthworks, formation, temporary facilities, and access visible in the current construction phase. The project will connect to the electricity system at 275kV, placing its civil engineering programme alongside substantial high-voltage equipment and commissioning work.

Energy-io, which is providing end-to-end design and delivery services, lists 120 Sungrow PowerTitan 3.0 units for the scheme. Each 20-foot container has a stated energy capacity of 7,144kWh, producing the project’s 857MWh total and creating a highly repetitive equipment layout once permanent bases and electrical infrastructure are ready.

That repetition changes the balance of construction risk rather than removing it. Much of the battery equipment arrives as manufactured units, so the site team has to make sure foundations, levels, cable routes, drainage, access, transformers, protection systems, and connection infrastructure are sufficiently advanced before a large volume of high-value equipment reaches site.

Energy-io describes its role as the engineering interface between Sungrow and the grid, aligning equipment compliance and commissioning through to energisation. The project is targeting the third quarter of 2027 for that milestone, giving the civil, equipment, control, and high-voltage programmes a common end point.

The transmission connection is a defining part of the build. A 275kV project has to coordinate the battery compound with protection and control systems, transformers, switching equipment, grid-code requirements, testing, and the connection assets needed before commercial operation can begin.

For the civil contractor, those electrical requirements translate into physical tolerances and programme interfaces. Repeated battery units and power equipment need prepared foundations and consistent levels; ducts and cable routes have to reach the correct positions; drainage has to control water across a densely developed compound; and heavy deliveries require access routes capable of remaining usable as installation activity increases.

Unlike a generation project where much of the process equipment may be assembled progressively, a battery scheme can receive a large share of its capital equipment in discrete manufactured packages. That can accelerate installation once the site is prepared, but delays to civils or connection works can leave costly equipment waiting for placement or commissioning.

Farrans says Berkswell forms part of BW ESS’s UK portfolio of larger, strategically located storage assets and will support flexibility close to major electricity demand centres. The contractor identifies frequency response, Dynamic Containment, and Capacity Market participation among the services battery storage can support once operational.

Those market functions sit beyond the construction programme, but they influence the technical package being built. Fast response and repeatable dispatch require control, communications, power conversion, protection, and battery management systems to operate as an integrated asset rather than as 120 independent containers placed on prepared slabs.

Commissioning consequently carries a larger role than the visible proportion of the programme might suggest. Individual systems can be mechanically complete while the project remains unable to energise until protection settings, controls, communications, equipment tests, and grid interfaces have been demonstrated in sequence.

The same applies to construction logistics. Once groundwork gives way to equipment installation, repeated deliveries can accelerate quickly across the compound, creating pressure on lifting plans, temporary routes, storage areas, and the handover of completed zones. Civil and electrical teams have to release those areas in a controlled sequence rather than attempting to complete the whole site as one undifferentiated work front.

The current early works are therefore establishing the geometry and logistics for a much more equipment-intensive phase. Earthworks and site formation may account for a modest share of the project’s eventual installed value, but errors at that stage can be repeated across dozens of foundations, cable interfaces, and container positions later in the programme.

Berkswell will eventually contain 120 battery units linked to a 200MW connection, with 857MWh of stored energy available within the installation. Before that capacity can enter service, Farrans, Energy-io, Sungrow, BW ESS, and the wider delivery chain have to keep civil construction, manufactured equipment, 275kV infrastructure, and commissioning aligned through to the Q3 2027 energisation target.