ELECTRIC POWER

New Zealand Times, Volume LIII, Issue 12616, 29 November 1926, Page 8

ELECTRIC POWER

MACHINERY SUPPLIES BIG CONTRACTS LET. Tenders aggregating over £130,000 have been accepted by the Government for the .supply of the principal machinery to complete the first section of the main hydro-electric scheme utilising water from Lake Waikaremoana. The successful contractors, in every case supplying British goods, are: Two steel pipe lines, Dunedin Engineering and Steel Co., £5869; two generators, Metropolitan Vickers Electric Co., £29,242; turbines, Sir W. G. Armstrong Whitworth, London, £21.GB6: indoor control gear, with switch gear, Cory, Wright, and Salmon, on behalf English Electric Co.. £5424; transformers. 110,000-volt, Metropolitan Vickers Co., £15,794. MANGAHAO The demand for hydro-electric power from Mangahao supply has bo greatly exceeded expectations that one board in the Wellington suburbs (the Hutt Valley Power Board) has to raise additional £150,000 for further reticulation. All the boards supplied from Mangahao are well ahead of their guarantees, and consequently Waikaremoana will be required to take a good load when the first section of the scheme is completed. The work is being done under the same system at Mangahao, the Public Works • Department doing nil the heavy construction, securing its pipe line and machinery by contract. The tenders just accepted comprise the largest portions of the esuipment, but a further series for machinery not requiring so long a time for construction .will he closed about January. WAIKAREMOANA Waikaremoana has an • ultimate capacity of 120,000 kilowatts, hut the scheme for which the machinery has been purchased will develop in the first section 40,000 kilowatts. It comprises two generators of 20.C00 kilowatts driven direct from Francis type turbines, the alternator running at 4*h revolutions per minute. A feature of the power-house, which the Public Works Department is constructing is that only a limited amount of switch gear will be housed in the station, the balance of the transformers and hightension gear being of the outdoor type, to bo erected on a site adjacent to the power-house. The latter is to be placed on the Whakaramarino flat. 1070 ft below the level of tbe lake, and tbe fall to be utilised will be that from Kaitawa Lake, its flow being augmented by diverting water from a river. CONNECTING UP The supply will be taken in an open cut through a tunnel 680 ft in length to the surge chamber at the head of a double line of steel pipes about six feet in diameter, and having a fall of 670 ft to the power-house. In anticipation of future demand, power lines have been surveyed to connect with Mangahao power at Napier, as this system will reach that point in January. Tenders are now ’-eing called for the towers required on the Wai-knremoana-Napier power line. The northward line is also planned, and a sub-station -for tbe Gisborne supply area is to be erected near Patutnhi.