SOUTH ISLAND POWER

Otago Daily Times, Issue 26746, 15 April 1948, Page 4

SOUTH ISLAND POWER

OUTLOOK FOR THE WINTER

Big Projects Take Shape in Waitaki Basin

To householders and industrialists throughout the South Island the vital question on the eve of winter is how much electric potver will be available in the months ahead. While it is impossible to foretell accurately what the supply will be as frosts become increasingly severe, at the moment there is no need for rationing. In fact, any rationing in the south at present is not only unnecessary but Avould be wasteful as reduced generation at Waitaki would only send the water over the spillway. While the power situation in the south compares more than favourably with that in the North Island, it is apparent from the schemes contemplated for the Molyneux, the Waitaki and the Sounds that the South Island has vast potentialities and that the development of its natural power resources will lead to a huge industrial expansion. The great power needs of industry in the future are at present being considered by the experts, and projects are planned that will keep the supply always well ahead of any possible demands.

The immediate question is what power will be available this winter. A satisfactory answer cannot be given at this stage. Too much depends on the rainfall, the amount of snow that falls, the severity of the frosts, and, of course, the consumption of power by the public and by industry. At the moment, however, there is no thought of rationing. The lake at Waitaki is being controlled to lip the spillway while three units —four at peak periods—are in operation generating 15,000 kilowatts each to supply the bulk of the power at present being consumed in the

southern part of the South Island. The temporary earth dam and the sluice gates at Lake Pukaki are being used to store water for use at Waitaki in the coming months. Lake Mahinerangi at Waipori stands at over the 78 feet level and Lake Coleridge, at 1672 feet, is less than an inch off being full. The outlook, therefore, appears brighter than it was at this time last year. Effects of Severe Frosts It must be remembered, on the other hand, that in spite of restrictions on certain types of electrical installations the consumption of power increases annually by from 7 to 10 per cent. While Waitaki is full at present and additional storage is now available at Pukaki, severe frosts soon stop the run-off of waters into the storage basins. At the moment the units at Waitaki are being run so that the water is kept at the top of the dam. When water has to be released from Pukaki to aid the constructional work, Waitaki takes an additional part of the southern load, thus relieving Waipori and Coleridge and enabling the storage at these schemes to be maintained. Such a happy position will not continue when the winter sets in. Then Waipori and Coleridge will be fully used and the generating units at Waitaki will operate on the normal intake available and what can be released from Lake Pukaki. It is believed, therefore, that during the severe period of the winter, when the generation of power at Waitaki is reduced and power consumption is high, some rationing may be necessary. It is unlikely that it will be nearly so harsh as last winter, when a saving of 33 1-3 per cent, was required. Activity on what could almost be called a vast scale is taking place from Waitaki through to Lake Pukaki and Lake Tekapo. At Waitaki the installation of a fifth unit is being carried out to bring the station up to its full generating capacity of 75,000 kilowatts. A special camp has been built to accommodate the 35 men required for this important work. Fifth Unit at Waitaki The foundation for the fifth turbine is being built at present, and the massive steel rings are being fitted to take the new unit. A fifth transformer in small groups.”

bank and overhead cables are being installed on the outer wall of the powerhouse, and a fifth bay is being prepared for handling the additional power that will pass through the outside switching station. This week over 200 tons of machinery reached Timaru in the Sydney Star for this new unit at Waitaki. The railway line from Oamaru to Kurow has been strengthened and improved to take the heavy equipment, and motor transport will convey the various parts from railhead to power house. It is expected that the wcajk of installing this fifth unit will be- com-

pleted before the winter of next year. Even then, Waitaki will be able to produce only a-quarter of the planned output of the new Roxburgh scheme. At Lake Pukaki approximately 240 men and thousands of pounds’ worth of modern constructional machinery are being used to form the lake into a great storage basin for the Waitaki scheme. The temporary earth dam has been completed and the sluice gates are in operation, while at present the site is being prepared for the main uttttttamitintmnmxiitixtiitiinttttitnxit

earth dam that will raise the level of the lake 30 or 35 feet. At Tekapo, fast progress is being made with the tunnel for the power scheme that will generate 25,000 kilowatts. The tunnel, with its intake control gates, and the subsequent damming of the river, will turn Lake Tekapo into another storage area. Lake Ohau is also receiving the attention of experts and it may be used to complete the chain which will serve the Waitaki power house and subsequent projects on the river.