POWER SCHEMES

Evening Post, Volume XCIX, Issue 120, 21 May 1920, Page 8

POWER SCHEMES

TO THE EDITOR.

Sir, —In reference to the advocacy by the Central Progress League of pushing on the development 01 hydio-c'.ectrx energy, including the harnessing of the Hutt River as a F.ta::d-by for Wellington City, I appreciate the iiinvw letters and articles in the presu boilr i'oi- ;;;:d against our .proposals. They .ill sarve a useful purpose in bringing tho {,-ocitior. before the public, and focussing attention on the urgency of and benefits to be derived from the utilisation of the tremendous resources of power ai Dreuer.c going to

waste,

Many people take me to tssk in assuming that I oppose Mr. Perry's proposals in bringing forward ihe merits of the Hutt River scheraa. Perhaps I have failed to make the attitude oi' the Central Progress League plain. Let ma restate it:—

(I) To urga the completion of Manga hao. with ail possible speed. ■

(2.) vo develop Waikaremosjia, in orriar that thesf powers may be interlinked, in accordance with Mr. Perry's scheme, at the earliest possible dste. ■

. These two r-ov.rcea of supply won id provide ail tie power required in the districts concerned for many years to oome. But if both sources of supply are harnessed it will st-i.i be necessary for the city to have a "stand-by plant in case of a break-down in ther-e hydro-electric powers. Tho City Co:.nci!, realising this necessity, has decided or. a very large expenditure for the improvement of their steam (power plant-. On account of the probable riss in fee coat of- coui snd labour, and the uncertain supply of both, the Central Progre&s League is ardently supporting the Kuti Elver power ccheme, in preference to any proposal to extend the present system of power supply, which is expensive to run to-day, and in connection with which the chief factors, coal and labour, s.re always likely to become dearer and uncertain of supply. Wo therefore advocate tli3 development of the Hutt -River as a stand-by power for Wellington City and the Hutt Valley.

Messrs. Hay and Vickermann state that ths Hutt River would develop 8000 h.p., at a cost of £45 per h.p.—that, this would save the City Council £50.----000 per year, in comparison with steam power generated by coal. This is a clear and definite statement of policy. It has not, to far, been answered by the press. The Central Progress League is not committed or biassed in any way. All that we seek is the onrly supply of cheap power to our citytind district, but until we are shown that a further extension of steam power is more in the interests of the city than the development of the Hutt River scheme we must continue- to support the latter.

The question of the height of the dam ; danger from earthquake; suitability of the ground ; ■ interference with railway deviation are purely technical matters, and have been faced and provided for by the engineers concerned. The land required by the Hntt River scheme already belongs to the Crown, having been acquired for this purpose some years ajjo. » We are in entire agreement with the press in advocating that a body of representative engineers should go thoroughly into this question,' lind advise the people upon the points at issue : . ' 1. Will it be. necessary—when Mangahao is developed, and later on, Wai-; karemoana —for the. city to have a stand-by power-plant. 2. If so,-is it in the best interests of the city to extend the present steam generating plant, or to develop the hydro-electric resoui'ces of the Hutt River. ; The question of comparative time of construction, initial and running costs, and other points would, naturaily, be the big consideration. t The first cost of the Hutt. River scheme would, no doubt, be greater, but the running cost per annum. v.-ou!d, according to Messrs. Hay and Viekerman, save the corporation at least 1 £50.000 per year. A copy of. the report j of Messrs. Hay and Viekerman has been. : sent on to the City Council and will, no doubt, receivs their seriouji consideration. —I am, etc., G. MITCHELL. 19th May.

River.

TO THE EDITOR,

Sir, —Your leader of. tho 13th inst. on the Hutt scheme is very • much to tho point. A considerable amount of information is necessary before a decision can be made on the proposal. In addition to yo.ur own valuable questions, may I add the following:_ (1) Is 9000 n.p. the full load output of, and at, all the turbines? (2) For how many hours a day can the above power be maintained continuously (a) in a normal summer, (b) in a very dry summer? (3) What does the £45 per h.p. include "in detail? Any land values or water rights ? (4) 'What are the dimensions of the proposed dam? (s)' What- is the length of (a) tho tunnel, (b) the pipeline, (c) the transmission line? (6) Is the latter a singie circuit lins and at wha;' voltage? (7) How far is (a) the dam, (b) the powerhouse from the nearest railway station? . (S) What roads are available, and what require constructing? The construction of hydro schemes is always more costly and lengthy <han steam plants, and in' view of the jarge amount of 'labour and cement required for such civil works, it is difficult to see how the work can bo done in anything approaching the time required to erect a steam plan:. The point of comparison is not the total expenditure on the city scheme, which must include converting and transforming sub-stations, with distribution cables, but simply the generating plants and equipment to deliver the power in bulk to the sub-sta-tions. The two 3000 k.w. steam, sets proposed for the city station would-.be more than equivalent to the Hutt scheme, and should not cost more than £240,000 complete and installed in a new station.

Now, I question very strongly if the Kutt scheme complete will cost less than double that air.ount. TKe proposal is for a running plant until Mangahao is available, and then a stand-by plant until Mangahao is absorbed, with a gradual building up of an excess load. Ib it a sound proposition to-double your capital charges for standby purposes? If the Hiiti scheme is run at its full capacity' after Mangahao arrives, it will be a bad lookout for the public money in Mangahao, with the loss of its main load during its years of inception. The- cost of taking peak loads by steam and providing a standby would i bo much cheaper than by the Kutt j acheme. When the steam load reaches to | ! 3000 or 4000 k.w. above tho Mangahao] supply, then it is time to have the Hutt i scheme linked up, either by the city or tne Government, and even then I am confident that the steam plant will not be | wholly dispensed with. Apparently, tho ! estimated saying of £$5,000 per annum on ; the Kutt scheme is the city coal bill on I the present plants. TaKng the estimate in my first letter the coal bill for 17 million units would bo £33.000. However, the capita, chr^-es on the Halt scheme would be at least -321.000 per annum higher than for steam, leaving a difference of £12.000 per annum if the otaam plant were running the full load, but it •mil not be, so that the cost c£ rue! for peak load and standby purposes will be lower for some years thj,a .he 6::t:s- capiial chai-geij on the Hutt scheme. (i I greatly appreciate the remarks of "B.Se." Ho is quite correct about the single pfjEfts 80 cycie system. However, he \s apparently unaware that the Governmerii has fcpo ii-.p primr.;^- distribution at 11,000 volts o ph^S3 £0 cycljl", so an incennoiliate vbltatrp of 6000 is quite unr.euofssary. . The-. 220-440" volt sysisir. is aiso^ unouitabic, a" it .1.5 i; taiee-wtre method citric-:* lo~: <i.c, v^n^ie phase, or off each "leg" of tho 3 phaue. ...'.o simpiesr ana' cheapest method :.-. :o transform direct from 11.000 voh- vo 400-230 vol:a oalhc 3 pr.aee 4-wire system. Tlr'c system only iBo-lre'j about 8 p?~ ct'r.t. r:: the copvu-r -v.joivet: -jn tH> ii-fic-'U syrrfum. Yr. tli-, ii-.-tsciit- oysterr of '10 vo'.i3 .". re- j ta'.nc-c!, .". double t~an».\orin:itioii will be : required v.iih double lofio-j &:k! uooufc | tlirea ti.ir.ee. ihe capital cost. Jn acclitkn. ■

it will not be available for power purposes bayon-d small motors. The U.S.A. standard is 220-110 volts, a wire, which k much superior to that existing here; but even tins was highly developed before lamps, etc.. wore suitable for 230 volte, and therefore it- is too late for them to change over now. Thu_ cost of changing to the standard for this country 400-230 rolls will bo cheaper and more efficient than changing- to 110 volts 50 cycles. In connection \v\tii the station site, ihc con<litior.a r.ro different in every cc'se. WateT and fuel crs the first ruquiromona., tlion the ior.d centre if tho. site is cheaper thaa ti-.o cos" oi cables, to a position outside the city. It. Aro is not smtabb for ~0/!, is the fuel "B.Sc." recommends. If 'oil fuel was not in view for standby parpcsa.;. and the new coa! wharf is ;o be shortly completed, theii Ik Aro would nave some important advantages.—l ara, etc.,' ■ ENGINEER.

13th May, 1920.