Hydro-electric Powerstation

History: Hydro-electric DC power station Constructed in 1911 as part of the electrification of Maenofferen quarry and designed solely for its use. It is supplied from Llyn Bowydd and Llyn Newydd via pipes and is still in operation with its machinery largely intact.

Exterior: Square, slate rubble building with slate roof half-hipped to the S; plain bargeboards and deep verges to the N gable and a small tin louvre at the roof apex. Boarded entrance door to W face with an unglazed window opening to the L. Plain yellow brick chimney projecting from the SW corner with a low brick wall adjoining to the front. Upper loading bay to the rear with cast-iron pipe entry point; boarded doors. Various blocked and disturbed openings to the N gable, in part relating to the adjacent ruined engine house.

Interior: Raised platform to the E with central rail incline and pipework. 3-bay king post roof with gantry crane. Gilkes of Kendal turbine dated 1927 and a direct current generator by British-Thompson-Houston Co; switch gear also by B.T. H.

Listed as an exceptionally scarce example of an hydro-electric power station with largely intact machinery.

References: D. Rh Gwyn and A. Davidson, 'Gwynedd Slate Quarries', Gwynedd Archaeological Trust, Report No. 152, (forthcoming).