HYDRO-ELECTRICITY.

Otago Daily Times, Issue 19759, 9 April 1926, Page 10

HYDRO-ELECTRICITY.

“ MISLEADING PRESS STATEMENTS.” PRIME MINISTER’S REPLY. THE COST OF GENERATING, (Fjioii Ore Own Correspondent.) WELLINGTON, April 8. Recently an article appeared in the Napier Telegraph on the subject cf hydroelectricity in New Zealand. Interviewed on the subject to-day. the Prime Minister said the article contained many statements that were misleading. “The fundamental mistake made in the comparison of the Waikaremoana power plant with the existing plants at Lake Coleridge and Mangahao.” he said, “is that in the case of Waikaremoana the estimated cost of the generating station only has been compared with the total cost of the whole system, including generating station, transmission linos, sub-stations and a certain amount of distribution lines. In the other two cases the comparison of Mangahao with Lake Coleridge is also misleading, in that the cost of the Lake Coleridge development is given at March 31, 1925, at which time the developed capacity was not 36,000, but 16,000 h.p. the figure for Mangahao is given for some subsequent date. A considerable increase in the total capital cost for Lake Coleridge will he required before the horse-power mentioned is available. The capital figure stated however has. ns in the case of _ Mangahao, included also the transmission linos, etc., which are not included in the estimated cost of Waikaremoana, with which it is compared Before Waikaremoana can come into operation transmission lines would have to be built to Gisborne and Napier and in addition to provide the load necessary to make this station anything like a commercial success it would he necessary for it to take over considerable additional lengths cf transmission line to other sub-stations m the Hawke’s Bay and Wairarapa districts, which have been charged to the Mangahao system. •The department’s general policy in embarking upon a scheme of three_ major stations instead of developing Waikaremoana alone and requiring that station to supply the whole of the North Island is criticised. A scheme of development utilising one station was gone into very carefully before the present scheme was finally "decided upon, and complete estimates of the alternative development were made. Waikaremoana was considered in this connection, but the department’s engineers were emphatically of the opinion that even if one power station were to be developed for the supply of the North Island, that power station would not be at Waiknretnoana, but would bo at one of the larger sources of power on the VVaikato River, which were much more suitably situated for a general scheme of power distribution It was felt, however, that it was better to develop the power available in the three sources rather than concentrate in one station with the consequent risks in the long transmission lines radiating over the whole island. The installation of a single generating station would have necessitated going to a still higher voltage than the lIO.COO volt which has been adopted for the present scheme, and which is very consideiably in advance of anything previously attempted in this country. It cannot be denied that the estimates given in the report of 1918 have been very considerably exceeded. These estimates were definitely stated as being made on a basis not exceeding 12 per cent, increase on pre-war costs. At that time it was quite impossible to state what the trend of prices was going to be. Actually the costs of material have been very much more than 12 per cent. _ above pre-war costs, in many cases running to 250 and 300 per cent, above pre-war costs. If Waikaremoana had been commenced at the same time ns Mangahao the estimate for its construction would have been exceeded in exactly the same way as has the estimated cost of Mangahao. Indeed, it is probable that owing to the very large proportion of the total cost which is represented in pipe lines at Waikaremoana the actual cost of construction would have exceeded the estimated costs in an even greater proportion than it did at Manga* hao. , , As an example of the way costs rose during Hie periol when a great deal of the material for Mangahao was ordered it might be mentioned that whereas the original Coleridge pipe lines cost in the neighbourhood of £2O per ton of steel, the small pipe line w-hich was erected at \\ aikarenionna in 1922 cost over £IQQ per ton delivered in Wniroa without erection. About the same time the lowest of the tenders received for the Mangahao pipe linns was in the neighbourhood of £9O per ton. With conditions such ns those prevailing it is very difficult to say what the cost of Waikaremoana might have been if the construction of it had been commenced at the same time as Mangahao. It is pleasing- to note, however, that although prices have not come down to anything like a pre-war basis a very considerable reduction on the high prices ruling in 1922-23 has been obtained. For example, the Lake Coleridge pipe line built during the past year has cost only about £36 per ton, and it is hoped that future orders can be obtained at still lower prices. While the department does not fail to appreciate fully the value of AVaikaremoana as a source of power and has made due provision for its development in the general scheme of power supply, it is however quite emphatically of the opinion that the present scheme, which includes Mangahao, is the right one to have adopted in the general interests of the country. When Mangahao becomes overloaded Waikaremoana will be brought in to supply the additional amount of power required, and the department is hopeful that Waikaremoana under these circumstances can be built up at a very much lower cost than if it had been developed at the period of high prices during which the Mangahao development was installed. The districts more immediately adjacent to Waikaremoana have been so diffident n coming forward and guaranteeing to take the power when developed that this station must depend very largely on the growth of the load in districts further remote to make it commercially successful.