HYDRO-ELECTRIC POWER

Dominion, Volume 10, Issue 3171, 23 August 1917, Page 3

HYDRO-ELECTRIC POWER

DEVELOPMENT IN TASMANIA LECTURE TO PHILOSOPHICAL SOCIETY At a meeting of tho Philosophical Society at the Dominion Museum last night Mr. H. D. Cook, M.Sc, 8.E., gave an address on hydro-electric development in Tasmania. In tho course of his lecture he pointed out that 'the development in Tasmania had an interest for Sew Zealanders, not only because this relatively small island (whose area, population, and trade are about one-iifth of tho New Zealand figures) was close to us, and had generally the same conditions as Now Zealand, but also because tho two main schemes which are now working in Tasmania are both very similar to the scheme wnich the Government proposes to develop near Shannon tor supplying power'to Wellington and tho AVest Coast districts. Lauiicestou tor many years has had a hydroelectric scheme of a total capacity of I'MK) horse-power, and water power is used in some of the mines fo a fair extent, but the present developments may be said to date from 1911, when tho Complex Ores Co., which was floated, to manufacture electrolytic zinc under the patents -of Mr. Gillies, started to develop the Great Lake scheme in order to obtain a supply of cheap power. This work progressed steadily till towards the end of 1912, when it was stopped owing to financial difficulties as the work had proved more costly than anticipated owing to unforeseen conditions. On the advice of Mr. Evan Parry, Electrical Engineer to the New Zealand Government, the Tasmanian Government acquired the scheme, and at the end of 1914 work was restarted, the scheme was finally opened on May 6 of last year, although all details wore not completed until August of last year. The scheme has a capacity of 10,000 horse-power at present, and a further polton of 8000 horse-power is now under construction. In addition, extensions of two-units, each of 16,000 horsepower, are planned, and, will bo proceeded with as soon as the war is over. The power is now transmitted to Hobart, about 60 miles away, at a pressure of 88,000 volts, where if is used for supplying the town with power and light, running the trams r -etc. - Carbido works are in x course of erection at North-West Bay, some 15 miles away, further down tho harbour, which will be producing 5000 tons of calcium carbide per annum vury I shortly from electric furnaces. The Gillies electrolytic zinc process will also be worked at this point. The Amalgamated Zinc Company is erecting works at Risdon, near Hobart,. also with tho object of producing pure zinc by electrolytic methods. The first unit will take 4000 h.p.' and this company has the right to call on tho Government for power up to 60,000 horse-power. If such big demands should materialise the Great Lake schenie can bo considerably increased in capacity by diverting the head waters of the Ou«e into the lake. A little further east' of tho Great Lake lie Arthurs Lakes, where another big power scheme could be developed if necessary. Several other lakes and rivers in the central part of Tasmania promise'possibilities of power, and aro at present under survey. On the West ■ Coast tho . heavy rainfall has enabled the Mount Lyell Company to put in a- relatively cheap scheme at Lake Margaret. For a total cost of £1-10,000 four peltons of ah aggregate capacity of 8000 horse-power, wit'h the necessary head works, pipe lines, electrical equipment, etc, were' installed. The power is used in connection with the mining operations, reduction works, etc., and the coni- ' pany is Baving ,£60,000 per annum through this plant, so that the scheme will pay tor itself in less than three years' work. This scheme was begun in 1912, and was completed at the end of 1914. The high saving is due largely to the fact that tho company was previously dependent on firewood for generating steam, etc., and as the timber was cut on the neighbouring hills it got more difficult nnd costly to obtain the necessary supply. Already the fifth unit has been ordered, and tho sixth will bo installed as soon as conditions allow -it. The conipany is projecting a further expenditure of .£70,000 on the scheme for increasing' the plant, raising the dam, etc. Now that the value of electric power has been brought home to this company further schemes are projected, especially for pro-, viding power for the. Read Rosebury group of mines, which lie a little north of the Mount Lyeft mines. The Government is studying a projected sc'hemo on the King River which will have a capacity of at least 30,000 horse-power. This scheme will be financed by the Government, and the Mount Lyell Company will take the power from tho new station, which will bo close to its present mines, and transmit •, this power through the Lake | Margaret station up to the Bead Rosebury mines, which it is now working/ The Groat Lake • and ■ Lake Margaret Bcuc'mos were 'illustrated with lantern slides showing interesting details of the engineering features of tho work. In eacii case tho head under which tho peltons work is over 1000 feet, and tho long pipe lines conveying the water under this enormous pressure involve many features of interest. The control of the peltons under varying.loads is an important feature, and-the simple devices which have been adopted and which givo very satisfactory results wero also illustrated and described.