The Press MONDAY, AUGUST 4, 1952. Geothermal Steam Bill

Press, Volume LXXXVIII, Issue 26800, 4 August 1952, Page 6

The Press MONDAY, AUGUST 4, 1952. Geothermal Steam Bill

! The project for developing the exi tensive geothermal steam areas of ■ the North Island for the generation of electricity was inaugurated by the previous Government and continued by the present Government; perhaps this explains why the Geothermal Steam Bill was put through the committee stages in the House of Representatives last week with rather less explanation and discussion than the subject seems to demand. The bill provides for the control and use of geothermal steam to generate electricity and for the control of the tapping of geothermal I steam in special areas. Members no doubt saw in it a hopeful augury for i the eventual success of the project; for the Government obviously be- . lieved that a stage had been reached I where legislative authority and sup- ' port for the undertaking were necessary. There is no doubt at all about the very great help that would be given to the strained electricity generating resources of the North Island if the underground reservoirs of natural steam could be used as similar reservoirs in Tuscany are. The present installed capacity of seven natural-steam power plants at Larderello exceeds 280,000 kw., which is 100,000 kw.'s more than Arapuni's installed capacity, and nearly twice the present installed capacity of Coleridge, Highbank, and Waitaki combined. Geothermically produced electricity from natural steamdriven plant contributes about 6 per cent, to Italy’s total electric power production.

The Italian achievement, indeed, appears to have inspired the interest in New Zealand's geothermal steam reservoirs. An engineer of the Public Works Departfhent, while serving with the armed forces in Italy, visited Larderello at the suggestion of the New Zealand Government and furnished a report; later, a Government mission, including the chief engineer of the Works Department and the government geologist, visited Larderello. The 1949 statement of the Ministry of Works mentioned these visits, and said that a survey of New Zealand’s thermal areas—“ vast ’’ in comparison with those at Larderello—had been put in hand. Last year’s report mentioned that exploration of the Wairakei area had been “ pushed ahead “vigorously . . . with such plant as “ was available in the country Results had beenkuffieiently encouraging to warrant procuring heavier plant from overseas; this plant, the Minister of Works (Mr Goosman) said in Parliament last week, had arrived in Auckland and would soon be in use at Wairakei. The new plant, if it is heavy enough to drill large and deep holes, will begin a really effective phase in drilling holes to tap geothermal steam. It appears that hitherto the mining technique of sinking a number of small exploratory holes has been used; and this is probably so much wasted effort. Geothermic

power generation in Italy did not assume significant proportions until heavy drills and drilling operators skilled from long experience in oil and natural gas production were used. At Larderello, tool bits up to 23 inches in diameter are sometimes used in bringing in steam wells, ths flow of which in many cases exceeds (50,0001 b an hour, at steam pressures of 1001 b a square inch. Operations on such a scale, obviously, are costly; but the high cost is justified by the promise of great benefit. This is something that must be done on a big scale or not at all; and it must be done by men well equipped to handle the technical problems involved.

It is interesting to notice from the bill that the law applying to geothermal steam is to be administered by the State Hydro-electric Department This is probably satisfactory as long as the idea is to concentrate on using geothermal steam to produce electricity. But a point is raised about which little has been heard in New Zealand, and which finds no mention in the bill. The basic resemblance between drilling for natural steam and drilling for oil and natural gas is also found in the by-products field. Just as oil and natural gas yield a host of

petroleum-chemicals, so the natural steam at Larderello not only serves the generation of power, but is also a source of various chemicals, of which boric acid is the most important In addition to boric acid, for home use and export, Italy’s steam wells yield ammonia and hydrogen sulphide, and appreciable quantities of carbon dioxide. No doubt New Zealand’s steam wells would yield a range of chemical products, some, possibly, of commercial value. It would be scarcely within the field of the State Hydroelectric Department to exploit and possibly market a range of chemicals, though these might substantially off-set the cost of producing electricity from geothermal steam. If it is not too early to legislate for the control of a new source of powjer It is not too early for the Legislature to give some consideration to these relatively minor but still very important questions.