GEOTHERMAL POWER

Press, Volume LXXXIX, Issue 27132, 31 August 1953, Page 13

GEOTHERMAL POWER

CONSULTANTS CHOSEN FOR WAIRAKEI

PROGRESS OF SCHEME REVIEWED (Neto Zealand Press Association) “The h a NGTON ’n August 28 - 4! age bas now been reached consStante i app ° lntme "‘ of specialist SWiW® (Mr W q r„ the M ! nlster of Works ™ poosman) today. Mera aJSd n McT r B n nnOU ? ced that Mea srs capacity of Wlth “ lnltial Kr® a Establishment 7 at iabora'te hiCh Th he consaltan is will coladvfee eeneSn consultants will also at Wairakei powe? prSi? power p ™. agred SrS to t an w MdLellan C °ha"d head Of »h=? ei i d '? New Zealand‘the a specialist ,r i dcvalopmen t department, initiate «sis?°thT(Vve Thls consulta nt would * • ,9 v ® rn ment s engineers in duce a P? natlon °f proposal to prowere mad?, h Sai ? it shmn? i Londor > fan that ence -niis thl « teelf of Italian ex Peri- *?• J" ls the firm was well equipped kn ° WledSe °“ hc

Ro,. i „ Wol ' k l Minlstr y’ s Tests °f k alrea dy done at ** a ake h Jh e Minister said that, after of Wmk? e i„ act i Vity by the Ministry nJ? , ln . cloBe association with tr^l D R??I tm t nt 4 ? f Scien t>fic and Induswere h ’ the conclusions reached deride??? ? nc O“ ra ging. It was then „ d to check the feasibility of elecle o an,U e o7.w: P of b ’ e o^er ProdUCing * -..A*"? objective has now been reached, and it is certain that 20,000 ?°wer can be obtained from ehaijpw noles, said Mr Goosman. 2 e f r ’ drillin * of the first . bad been begun with a large Tig. and RoIUS to (16DthS Of 2000 ft and 3200 ft had now been drilled, *J2 le was a t present b £ lp S d ? iU .u d ’ and tbe productivity of be tested® gr ® ater depths W ° Uld flrst hole has been allowed to nl.l'sPS®?’ » ant ! equipment is now being E»i/?£ ed M -°< t . eßt the yield of steam, said the Minister. "It is without doubt much greater than that of any of the shallow wells drilled." One of the larger shallow wells had recently been measured, and proved to be discharging steam equivalent to 4000 k.w. of power, the Minister said. The deeper holes, of larger diameter and nearly twice the cross-sectional area discharged at a substantially greater pressure, so that it was not un. reasonable to believe that the discharge might be equivalent to 10,000 k w. of power for a single hole. The steam discharging from Wairakei usually contained a large amount of a l mo st complete separation of the steam from the entrained water fad peen proved to be entirely practicable, Mr Goosman said. It was possible that a somewhat better quality of steam might be obtained from the deeper holes, and the results of the tests now to be undertaken would indicate whether that was so. Corrosion Problem The entrained water in the separated steam contained various dissolved chemicals in small proportions, as well as very small quantities of gas, mainly carbon dioxide. A good deal of data on such matters, which were vital to turbine designers, had already been assembled, and.this information would enable plant designers to make a suitable choice of metals to minimise corrosion.

The amount of chemicals and gas present was, however, much less than encountered at Lardarello, and the problem was believed not to be serious at Wairakei, the Minister said. “The maximum power potential of <pe Wairakei area is. of course, not definitely known,” said Mr Goosman. ‘but the Department of Scientific and Industrial Research, in a recent report, stated 1 that at least 70,000 k.w. of power could be expected from shallow holes m the area.

rt These figures are based on estimates of the total natural heat escaping from the surface of the area, allowing for a conservative utilisation factor, but as drill holes, particularly deep holes, are likely to open up further paths for the flow of heat from the depths, it appears possible that the power potential is much greater,” concluded the Minister.