HYDRO-ELECTRIC POWER

Otago Witness, Issue 3384, 22 January 1919, Page 28

HYDRO-ELECTRIC POWER

THE NORTH ISLAND SCHEME.

THREE PROPOSED INSTALLATIONS.

Tho scheme prepared by Mr E. Pa ? r y> Chief Electrical Engineer, for tho establishment of a State hydro-electric system for the North Island embraces pr°P°*°g for tho development of three P» n "Pf power sources, at Mangahao, Waikaremoana, and Arapuni,. with resection that if the construction of tho dam re ■ quired for tho. last-mentioned fa practicable or at least inadvisable Aiapuni will be replaced by Aratiat.a, which * the next in order of merit as regards size and l ™ll°h recommended that in tho interest of national economy and P«**urtion &J scheme should be planned in such ajn«jn« and on such a scale that a supply of power shall be available With the <*-°V*™™* of the local authorities for every household in the North Island or tewyjj; dustry requiring the supply of power tern porarily or otherwise, for main-line electn ■fcoation, light railways, coal and other mines for winding, pumping, ventilating, • £X melting, and for any other pv mente outlined above a total sub-station gSI of 130,000 horse-power is neceesanyj > quiring a. plant capacity Ml the mam power sSoS of 160,000 horse-power, allocated as follows, viz. :-96,000 horse-power A ; ' puni, 40,030 horsepower at waitore moana, and 24,000 horse-power a Mang hao The power to be provided is equiva tent to one-Sth of a hope-power per head oi the present population of the JNortn JS «' The total capital expenditure is estimated at t .during: co£ recoverable in from six to .seven years in Dortina after a reasonable interval WW tnl a total of £767,728, requiring an average ing a M»im » , , üb . s tation load, return oi »o »s per a.y. y* ~, .v,. -Wails which is under consideration, but the details return should be easily secured. AGRICULTURAL RAILWAYS. «< Another branch of electric haulage which may pojsibly have an important influence £2n the destinies of New Zealand is the instruction of light railways which wou d ■ Svette roads of heavy traffic and would nromoto exchange between town and counTryTnd fo?m an important link between producer and consumer." CAPITAL EXPENDITURE. " The' complete estimate to provide for the general scheme of electricity supply outlined herein then becomes:— I Generating stations (total plant capacity, 160.00 J

In the event of taking over the Waihi Company's Hora Hora works a further sum dependent on the terms arranged with that company would have to be added. "Throughout this report estimates have been based on a rate not exceeding 12 per cent, above pre-war prices. With the present unsettled condition of markets and supplies, it !•> impossible to estimate exactly ' od work* destined to be completed some ' tir.mt ahesd; but even if the present high prions i-euain after the war the balance wili mill be in favour of such a scheme of devn.iopJ-.ent, for although the cost may be gre».t<»r &o coso °f au competing powers w ! »l also be greater in much the same proporti'in. It will probably take 10_ years to carry out all the works included in the obUovaw. Jti» initial expenditure on headwords wwfl be heavy, but, on the other h'«vi, to* pLuifc ■woul'' vnly be installed as r «-tjlw*d to meet the growth of the load. r !>o orrera.ge rate of expenditure on the above assumption would be about £730,000 p*t aiijiunv. FINANCIAL RESULT.

"X% may readily be inferred that, inasmuch as "rie estimated capital expenditure per horse-power does not exceed the expenditure per horse-power on the Lake Coleridge undertaking, tho financial result will be satisfactory. The capital charges for interest, depreciation, and sinking fund at 7i per cent, will amount to £547,728 per annum. The working expenses should not exceed £220,000 per annum, making a total annual expenditure of £767,728, requiring an average return of £5 9s per horse-power per annum per horse-power of maximum load. . "Further, tho total capital charges, including interest, sinking fund, and depreciation of 7g per cent., amount to seveneighths of a penny in the pound on the present unimproved Value of land in the North Island. We know, however, by experience of the Lake Coleridge undertaking, Hitvi even at vory lav rates for which compare favourably with rates charged in any part of tho world, sufficient revenue is obtained at an early stage of development to meet all capital charges, whilst at the same time values aro enhanced, production increased, and expenses <>f production diminished."

horse-power):— x Cost. Per h.p. Mangahao H-Jg Wadkaremoana ... Arapuni - 06 > 000 £ 438,054 644,360 1,078,700 £18.3 13.16 10.8 Total amount and cost per horse-power 2,061,723 12.88 Main transmission lines shown on drawing E1116 1,563,880 Extra branch transmission lines at lower voltage to main sub-stations not on main lines Main sub-stations ... ••■ 241,360 838,808 11.22 5.24 Distribution lines and secondary sub-stations ... 2,086,000 13.04 6,781,771 42.38 ' Interest during construction 271,271 1.69 ' Assistance to local authorities and power users ... 100,000 0.62 Working capital 150,000 0.94 Totals 7,303,042 45.63