HYDRO-ELECTRICAL POWER.

Wanganui Chronicle, Volume LXXIV, Issue 17695, 22 October 1919, Page 2

HYDRO-ELECTRICAL POWER.

THE WANGAEBU SCHEME.

MR. TALBOYS IN REPLY.

At a meeting of the Borough Council last night the following report was presented by the Borough Tramways engineer and manager (Mr F. P. Talboys) :—

A letter from Mr E. Crow has been published recently in the. two local ..papers, purporting to discuss my report to you on the proposed Wangaehu Hydro-Electric Scheme and my recommendations of a steam plant for our purposes. I don't think Mr Crow has made a contribution of any value on either subject, but desire to comment on his criticisms in case anyone should :be inliuenced by them.

I consider that Mr Crow might have refrained from attacking me personally Avhile discussing these questions. As he has not done so, 1 feel justified in pointing out that my sole interest on these matters is as a servant of. the public. Can he on the other hand, say that no personal advantage' Would accrue to him if the Wangaehu scheme was adopted?

Mr Crow expresses a strong desire to "cut out guessing;." How any person can anticipate future events without "guessing," or. as I should prefer to term it, estimating, is more than I can see and more than Mr Crow manages to do, but I think that the quality of this guessing leaves much to be desired.

MANGAHAO SCHEME. '#

Mr Crow warns us that the Wangaehu scheme cannot possibly be relied upon to supply Wanganui's requirements. There may be excellent reasons for a Wangaehu scheme, but this alleged inadequacy of the Mangahao scheme is not one. of them. Mr Crow's opinion on this point is directly contrary to the opinions held by. Mr Parry, late Chief Electrical Engineer 'to the Government, and Mr L. Birks, his success*oi*, shares Br Pai'ry's opinion. In connection with this I avoulcl refer you to a report from the Public Works electrical engineer (Mr Parry), published" in the "Chronicle" of October Kith, 1917, in which is suited: —

"As regards the area to be supplied, there is an economic .limit to Lfte area over AVhich a given amount oT power can be distributed, and one of the obstacles to a satisfactory '-clieme of power supply in New Zealand at present, is the small amount of power required per square mile of area supplied. Having regard to this principle, and stretching it to Ihc limit we should be working on economical lines in serving the following districts from this source: The whole of the Wellington province as far north as Taihape and Wanganui, and-the southern portion of Hawke's Bay. 1 would propose, in the first place, to run trunk lines to Wellington. PalmerstoU' North, Wanganui and Masterton, as chief centres, and from these centres, as well as from intermediate points on the trunk line, to provide for the necessary distribution lines and substations to serve the surrounding dis!trictf=."

Mr Crow's guessing on this point is rendered more defective., by two fundamental errors. He has apparently forgotten that the electrical consumption of each district will not be limited by the "electrical manufacture of that district, as the Government scheme provides for linking tip all the North Island power stations. He also'forgets that the Government scheme not only contemplates future development of its producing power, but also aims at providing for a demand in excess of what will be made for a good many years.

Mr Crow quotes figures giving the j actual amount of horse-power delivered per capita of population in different countries; this information evidently having been taken from a report of the Public Works Department, but he has apparently not realised that to be useful, such figures must be considered intelligently. We have some experience nearer to hand than America or Norway, and With a more practical bearing on our particular problem. Dunedin, after fifteen to twenty years' run 1 ning, at present absorbs .125 horsepower, and Wellington .12 horsepower. Mr Crow has guessed .2 horse-power for this district, basing his guess on the fact that the North Island scheme, looking well ahead, provides for that output. It must be admitted that Dunedin and Wellington are more highly industrial is:;<l than Wanganui, and have been twenty years or more working up to this present consumption, and yet they are still a long way short of what Mr Crow considers necessary for Wanganui "right from the outset." * PROPOSED WHANGABHU SCHEME. Mr Crow accuses me of desiring to squash Mr Poison's scuerue. This accusation is contrary to fact. I was asked to report on a conditional offer made by Mr Poison to supply from the Wan en eh v River a minimum oi" 2000 h.p. at £12 per h.p. per 'annum, the price to be reduced by £1 for every. 1000 h.p. taken over this minimum. I think I was doing no more than my duty pointing out that this offer

should be carefully investigated in view of the adverse opinion on the ' Wangaehu as a source of hydroelectric power expressed by the late i Mr Pr"STHay. Mr Hay's opinions j are not to be set aside merely be- | cause Mr! Crow boldly asserts the j contrary. Neither do I hold that Mr Hay was infallible, but I consider that before dropping the assured source of supply offered by the Government scheme, the Borough ought to require from the promoters of the rival scheme reliable expert opinioil on the feasibility of their scheme.

As an additional reason io those furnished by Mr Hay's report for regarding the Wangaehu scheme critically, I have recently received information that guaging3 in many of the North Island streams; the Hautapu and Mangawhero for Instance, over a considerable period have given very considerably smaller flows than are assumed in Mr Hay's report. It is, therefore, quite likely that if the Wangaehu had been constantly guaged over a long period it's minimum flow would be found to be much less than is estimated. It would be interesting to know how many guagings. and at what seasons, Mr Crow has taken of the Wangaehu.

Wit\i regard to the price that Mr Poison names—£l2 per horse-power, I stated that I consider it too high. Mr Crow retorts that the cost from a steam plant would be £19 per h.p. I should, like to ask him how he gets this figure, and in particular what load factor he assumes or guesses. But steam costs have nothing to do with the case. If steam power was as cheap as water powerj there would be no need for a hydroelectric scheme. The real rival to the Wangaehu at £12 per h.p. is the Mangahao at some figure yet to be fixed. As an aid to "guessing" what that figure will be we know that the Government sells power from Lake Coleridge at £6 10s per ii.p. for the first 300 k.w. and £3 15 per h.p. for all in excess of 300 k.w. Mr Crow attempts to discount this fact by staling that Lake Coleridge is run at a loss. It is true that tife first four years showed a loss —very slight in the fourth year, but it may surprise Mr Crow to learn that the current year is expected to show a profit and make a start at paying off arrears. Many successful industries have had a similar experience ot' losing money until c market for their output was treated. The Government engineers cannot yet say what the Mangahao cost is to be, but Mr Crow has decided that it is to be £11 9s per h.p. I agree that it may be higher than the Lake Coleridge charges of £6 10s and £3 15s; because wages and material are higher than when the Lake Coleridge undertaking was carried out. Suppose we say 25 per cent, higher, that would still admit of a much lower charge than the £12 per h.p. suggested by Mr Poison. As an illustration of Mr Crow's looseness and inaccuracy, 'it* is worth comparing, with the facts, his statement .that "the -estimated cost of Lake Coleridge was some £230,000, whereas, up to the present, about £390.000 has been expended." The cost of Lake Coleridge works was £269,342, which is very close to the original estimate. The balance of the £390,000 is /mainly distribution items. Yet it is largely on this imaginary discrepancy of 70 per cent, between estimated and actual cost of Lake Coleridge works, that ; Mangahao scheme upon Which he !Mr Crow arrives at the cost of tlio i Mangahao scheme upon which he ; bases his. figure .of all Cs per h.p. i Against Mr Crow's absurd guess I [have authority- for statfaxg that power will be sold by the Govern|iiient on the same basis as at ColeI ridge, and that loads of similar magjnitude and nature in any part of the country will receive similar rates, also that though our rate may be slightly higher than the present Coleridge rates, it is also possible that if the total'load can be put up to any extent, these rates might be reduced.

Apropos the idea o£ a local scheme like the Wangaeliu for our district, I am privileged to quote the following from a paper yet to be published by a leading electrical engineer:

"It is now generally recognised I that a multiplicity of small stations does not lead to economical operation. During the reorganisation of the war period, both in England and j America, the tendency everywhere has been to amalgamate small power Concerns and interconnect their supply systems to affect economies in coal supply and in labour. Thers are many economies to be effected in this way. It takes practically the same stafl: to operate a station, particularly if a water power station is considered, of 500 h.p. as it takes to operate one of 5000 h.p. or even 50,000 h.p. The cost of the machinery per h.p. will be considerably less (with the larger aized units, and the j efficiency will be greater. Then ! again, the total amount of installed plant.can be considerabty less because instead of each small station haying to carry extra spare plant considerably' in excess of its normal (requirements to meet . sudden de- ■ mantis or breakdowns, a limited I amount, oi spare plant will be cari ried in the central station which j would bo available for a breakdown lor emergency load on any section of its distributing system. Also the I plant in a:iy one station has to bs j proportional to curry the maximum I ioail thai may bo thvov/n on it, but | there- is always, si diversity in the ipcak load,'; of dilYorent places. They Ido not all occur exactly ;u the fuuae ; iimc .so that the plant capacity of a |central station supplying several disitricls need not be courti to the sum •of the peak loads likely to occur on jits various feeders. This has been j taken advantage of to a considerable 'extent on existing pJanis in Eugiaiul, (where systems have been- interconnected and it is found that by rtuinihg the larger and more economijcp.l plaiitw nearer to their full capacity it has been possible to close I down sonic of the •smaller and leys ■economical generating plants altoIgether."

STAND-BY PLANT,

The nece^siLy for a stand-by plant does not admit of any discussion. As no suggestion has bt'en made that a stand-by plant is proposed to be Installed an a part of the Wangaehu .scheme it is evident that Wanganui must supply its own stand-by. The only question then at issue is what type of plant is most suitable. Mr Crow. favours a suction gas plantMr Crow's opinion does not coincide with that of any expert I have heard of when dealing with requirements of any magnitude. There is no need to repeat here the arguments adduced in my report of August Bth, 191.9, in favour of a steam plant, which may he summarised in the statement that the suction gas engine is not suitable. One remark I would like to make is that suction ;;as, is no better than steam for intermittent service. If town gas were used for this class of work would the Borough Gas Works be prepared to supply, for four or five hours, the ne-