BORED FOR SALTS AND GOT STEAM POWER

Taupo Times, Volume I, Issue 2, 23 January 1952, Page 5

BORED FOR SALTS AND GOT STEAM POWER

Taupo residents ~Ior some months past have be*sn made aware by sundry explosions and noises like giant, engines blowing off steam from tbeir saiety valves, of the prog)ressive explorations in tbe Wairakei region of the possibilities of harnessing the steam from Nature's iS'ubterannean boiler houses for electric power. Opportunity will be taken at intervals of reporting to our readers on these developments. Apart from Taupo's more immediate interest in its own hydro-power scheme on the Hatepe, the story of Naly's experience with underground steam is worthy of more than a passing reference. "The ancients," said Mr Christopher Serpell in a talk in the Home Service of the B.B.C. "found that the water in the Larderello Valley in Italy had medicinal properties, and in the late eighteenth century learned men found that the principal constituent of their deposits was what they called 'Homberg's Sedative Bait' — in more modern language, boric acid. "By the nineteenth century an industry had sprung up to extract borax and boric acid both from the water and from the mixture of gases and natural superheated sfeam which was found to be making the bubbles. This steam was also used to heat the boilers in which the water was being evaporated, and as the industry developed, more and more attention was concentrated on it. The idea grew that there must be somewhere underground a vast reservoir of this steam, and drilling operations were begun to tap it at other places than the natural escapes. It was difficult and dangerous work. The bores had to be carried. doep into the earth; sometimes the steam failed to appear, and sometimes it burst forth with a rush of debris and boiling water. "By the beginning of this century several artificial blow-holes had been established, and efforts were being made to use the steam not only for its chemical properties but also for its heat and energy. There were mtany technical difficulties, due mainly to the chemical effeets of the steam on the apparatus, but by 1905 an engine, driven by natural steam, was operating a dynamo and supplying electric current to the whole boracic industry plant at Larderello. "Between the two wars the situation was revolutionised by the use of new drilling techniques and improved apparatus. In 1931 one of these drills had reached the depth of 877 feet, when there was a tremendous explosion and steam at a temperature of 401 degrees Fahrenheit came rushing out of the hole at a pressure of 50 pounds to the square inch, and a capacity of 220 tons an hour. This enormous supPly °f natural energy was successfully harnessed and since then, with an interruption due to the second world war, drilling operations have been pressed forward. "Today there are more than 140 of these blow-holes, some of them are a mile deep, all pouring out super-heated steam which is converted into electric energy. I recently visited the plant- and saw the whole hillside interlaced with huge metal pipelines leading from the various blow-holes.