GEOTHERMAL STEAM FOR ELECTRIC POWER

Taupo Times, Volume IV, Issue 195, 21 October 1955, Page 4

GEOTHERMAL STEAM FOR ELECTRIC POWER

Drilling for geothermal steam in the thermal zone of the North Island could result in the supply of 200,000 kilowatts of electric power, says an estiinate in a bulletin, "Geothermal Steam for Power in New ZealandThe bulletin is published by the I)(4partment of Scientific and Industrial Research and c'ompiled hv Dr L. I. Grange, of the Geologieal Society. Many Centres Tested The natural heat-flow from 14 centres, of which Wairakei, Waiotapu and Orakei -Korako have the highest flows, totals 7390 million Kritish thermal units an hour. This total, says the bulletin, can be roughly converted into terms of electricity to give a total power potential for these areas of about 250,000 kilowatts. As it is u n likely that areas capahle of yielding under 10,000 kilowatts will be brought into production, the total can be reduced to about 200,000 kilowatts. This figure is hased on heatflow at the surface, and it is apparent that at least this amount will be obtained on drilling. How much more can be tapped is not known. In additlon there is a great store of heat in the high-temperature unclerground water in the thermal region. This is a great bank of energy, but for how long and at what rate it could safeiy be drawn upon is not known. 30 Holes Sunk Although drilling has been concentrated at Wairakei, geologieal, geophysical and other scientific surveys have been made over many parts of the thermal region. At Wairakei 30 troles have been sunk to depths of Crom 574 feet to 3200 feet. Half of these are regarded as development

wells and the remainder as exploratorv. rIhvo of the deeper eight-incli bores have a combined outpnt of more than 17,100 kilowatts. A contract is to be let. shortly for the construction of a power station of 40,000 killowatts at Wairakei to operate in conjunction with a plant extracting heavy water. It is planned to double this outpnt.