Moore Street Electricity Substation

Moore Street Electricity Substation

This is a listed Grade II electricity substation situated on the north-west side of Moore Street at its junction with Hanover Way. Built as a functional modernist industrial structure, the building comprises a long, rectangular plan with an angled south-west end. It contains a cable basement, two transformers on the ground floor, switchgear on the first floor, and a second floor originally designed for busbars but now empty. The various floors are linked by external staircases and covered walkways at the east corner, with some floors also connected by internal staircases.

Exterior

The Moore Street elevation is the principal façade, consisting of seventeen bays of reinforced concrete portal frames set mainly at 21 feet (6.4 metres) centres along the building's length. The first two bays are angled to face onto a roundabout, while the tenth, eleventh and twelfth bays on the first floor project slightly forward. A deep chamfered floor plate runs between the ground and first floors, with projecting rectangular floor beams at the bay divisions. The floor plate between the first and second floors forms a string band with similarly projecting floor beams, and a comparable eaves band runs across the top. The roof is finished with flaring coping panels that are gapped at the projecting roof beams, creating a castellated effect.

At ground-floor level, the two angled bays and the third, fourth and fifth bays feature spaced concrete vertical slats with glazing behind them. Those in bays three to five have set-back blue brick infill panels beneath. The remainder of the ground floor has set-back blue brick infill between the portal frames, except for bay eleven, which also has vertical concrete slats. Bays eight to sixteen have projecting low flat-roofed blocks, similarly detailed with concrete portal frames, deep concrete roofs and blue brick infill. Concrete roof ventilators sit on the slightly lower block covering bays eight to ten.

The first floor is clad with horizontal aggregate panels fixed over the concrete portal frames with narrow gaps between them. The second floor has similarly spaced cladding panels, which are set back between the portal frames. At the east corner is a free-standing external staircase, now enclosed at ground-floor level by a blue brick wall. The staircase is triangular with chamfered corners, featuring a triangular board-marked concrete core with a sloping top that projects above the actual steps. The concrete flights wrap around the core on cantilevered brackets. At ground-floor level the staircase walls are infilled with blue brick; at first-floor level narrow vertical concrete slabs are used, while the three upper flights are glazed with narrow vertical glass panels.

The north-east end elevation comprises two bays with a third, narrower bay cantilevered out at first-floor level, with similar detailing to the Moore Street elevation. At first and second-floor levels are enclosed cantilevered walkways opening from the external staircase, both with concrete floor and roof slabs and glazed with narrow vertical glass panels.

The south-west end elevation is a single bay, detailed similarly to the two angled bays on the Moore Street elevation.

The Hodgson Street elevation spans fifteen bays with similar detailing to the Moore Street elevation, but with the first floor cantilevered on large triangular brackets supporting the floor beams. The first floor projects slightly in bays six to eight, mirroring the projecting bays on the Moore Street side. The underside of the projecting bays contains a large access hatchway. Bay nine contains a projecting semi-circular staircase outshut at ground-floor level, built of blue brick.

Interior

The ground floor contains two large, mirror-image transformer rooms separated by a transverse access way, with high ceilings designed to allow the orange brickwork between the concrete portal frames to be removed to facilitate insertion and removal of equipment. The transformers are set into large pits. Outside each transformer room is a room containing cooling equipment, open to the Hodgson Street elevation. Opening from the south-west transformer room is the semi-circular staircase, which connects the ground floor with the cable basement and a self-contained mezzanine level housing an air receiver container room and an air compressor room. The staircase features concrete flights rising around a slab-like concrete core with semi-circular landings and plastic-coated metal handrails attached to the inner core.

At the south-west end is the ancillary personnel area, with rooms opening from an irregular pentagonal circulation space containing a free-standing concrete staircase. Three flights of concrete steps overhang a central concrete beam and angle around two intermediate landings to form a triangular shape; the landings are supported on circular concrete columns. The swept balustrades are of metal square-section bars with black plastic-coated handrails. On the north-west side is a personnel lift in a concrete shaft, and the other walls in this public area are of blue brick with small square blue-glazed tiles on the floors and as skirting. Doors opening from both ground floor and mezzanine landing are of narrow vertical boarding in a wider stile and rail frame. On the north-east side of the lift is a second concrete staircase with metal balustrades rising from the mezzanine level to the first floor, with steps rising around a slab-like concrete core and intermediate semi-circular landings supported on projecting horizontal beams.

The first floor is a single open space with switchgear equipment in fenced-off areas. The access hatchway has a pivoting metal hatch. Rolled steel girders and winches are attached across the width of the concrete ceiling to facilitate equipment movement. A large rectangular hatch in the ceiling, now covered, originally linked the switchgear with the busbars on the second floor. A doorway in the north-east end wall opens into the covered walkway linking to the external staircase.

The second floor is presently empty. At the north-east end is a largely free-standing concrete staircase leading to the roof, with three flights of steps rising between intermediate landings. The lower landing is supported on a circular concrete column and the upper landing rests against the end wall. Metal balustrades match those elsewhere. A doorway in the north-east end wall opens into the upper covered walkway linking to the external staircase.

The cable basement contains shallow concrete troughs for cables. In the east corner is an internal staircase leading to a door opening adjacent to the external staircase.

Note: The electrical equipment contained within the substation is not considered to be of special architectural or historic interest.