GEOTHERMAL POWER

Press, Volume LXXXIX, Issue 27047, 23 May 1953, Page 9

GEOTHERMAL POWER

£5,000,000 PLANT PROPOSED APPROVAL BY CABINET (New Zealand Press Association) WELLINGTON, April 22. The Cabinet has approved in principle the construction at Wairakei of a combined plant to produce electricity and heavy water by the use of geothermal steam. Announcing this today, the Minister of Works (Mr W. S. Goosman) said the estimated cost of the project was £5,000,000. The Cabinet’s decision, he said, was being followed up vigorously by the departments concerned—the Ministry of Works, the State Hydro-electric Department, and the Department of Scientific and Industrial Research. An intensified drilling programme, on which £200,000 would be spent, had been started, to obtain the additional amount of steam required for the combined project. Mr Goosman said the Cabinet had also authorised him to engage a consultant in steam engineering to work with the State Hydro-electric Department and the Ministry of Works, in co-operation with the United Kingdom Atomic Establishment at Harwell, which was interested in obtaining a supply of heavy water for use as a moderator for atomic materials. . Corrosion and other tests estimated to cost a further £9lOO would be carried out by the Department of Scientific and Industrial Research, he said. Mr Goosman said that the opening up of the recent deep bore at Wairgkei had brought in a new phase in the work of prospecting for geothermal steam. The pressure of steam issuing from this deep bore was about twice as great as that of the steam irom any previous bore. With the valve closed, the pressure reached 4501 b a square inch, and during delivery the pressure on a gauge only 10 feet down from the open end of a pipe eight inches across was maintained at about 1101 b a square inch.

Resources of Power The measurement of this well was presenting some difficulty, but on the assumption that the product of the well was similar to the product from other bores measured at Wairakei, the available power from the new well was thought to be between 5000 k.w. and 6000 k.w., said the Minister. On this basis, the output from one bore, compared with a similar production of power by the burning of coal, would result in a saving of about £60,000 or £70,000 a year, if the price of coal was taken as £2 10s a ton.

■ One or two preliminary bores put down at Te Teko, about 50 miles from Wairakei, had indicated the presence there also of geothermal steam in considerable quantity, said the Minister. There was now available at Wairakei a total of about 20,000 k.w. of power from the bores already sunk. The Government had now agreed in principle to combine at Wairakei a plant for the production of power with a plant for the production of heavy water, in accordance with the wishes of the British Government, provided the necessary additional steam could be proved, Mr Goosman said. The proposal would be treated as a joint venture between New Zealand and the United Kingdom. This decision necessitated the sinking of more bores, as a considerably larger quantity of steam was now required, he said. Work on the second deep bore was already under way. Mr Goosman said the departments involved had proceeded with the greatest caution to ensure that the supply of steam from the wells already opened had shown no diminution, and that one well did not interfere with another. Until now, there was no evidence of deterioration of supply in any respect.