b.—i

82

transmission-line would gel ihe benefil of the lower rate. Ai such rate I estimate thai within five years the load taken over would be as follows, allowing for the normal growth in each city during that period. and allowing also a most important point—that 100-horae power of steam and gas engines can usually be replaced by 60- to 80-horse power of electric motors, owing to the saving in shafting, belting, and mechanical transmission losses, and the capacity of the motors for occasional overloads. The probable power of steam-engines and gas and oil engines remaining is also shown : —

These estimates show a reduction in the total nominal horse-power in each case, although the actual power employed in these factories will be from 10 to 20 per cent, greater than ai present. It will also be noted that I do not estimate any serious falhng-off in the business of t he existing gas-supply concerns. No doubt a good many gas-engines will be replaced, but this should be quite counterbalanced by the normal increase of business in motive power, lighting, and cooking. The rates may have to be reduced slightly to retain this business ; but such reduction need not threaten the stability or successful results of the gas companies undertakings. Allowing an average load-factor of the factory and general motors of 12") per cent, and a maximum total demand at any moment at 55 per cent., the full rated output, the power-requirements, and the estimated revenue from this source in five years' time would be as follows : —

Average revenue (pence) per unit .. .. .. .. . . l-25d. Units sold per rated horse-power .. .. .. .. .. 820 Average revenue per rated motor horse-power per annum .. .. £4 ss. Revenue per average actual horse-power for forty-eight hours per week . . £9 16s. Revenue per maximum horse-power demand .. .. .. £7 14s. Revenue per maximum kilowatts demand .. .. .. .. £10 ss. These figures are well on the safe side. A load-factor of only 12-jj per cent, is estimated, whereas the Dunedin motors already show a load-factor of 14-6 per cent. It is certain that this figure would be improved on. with consequent improvement in the revenue. The consumption per rated ho.rse-power is estimated at only 820 units, whereas Dunedin already shows 1.285 units, and Christchurch, at 3d. to 2£d. per unit. 792 units, per rated horse-power. This power-load woiild have a fairly steady maximum of the amounts shown from 8 a.m. till 5 p.m., with a dip from 12 to 1 p.m. It would then fall off to about 30 per cent, of the maximum throughout the evening till 9 p.m., and then down to about 20 per cent, lor the all-night load. Electric Lighting. In estimating the future demand an enormous development must be provided for in electric light ing. The present charges for electric light range from 7d. to sd. in Wellington, with an average revenue of 6-29 d. per unit, and 6d. to 3£d. in Christchurch, with an average revenue of 5-ld. per unit. In Dunedin, on the other hand, the price is sd. to Id., with an average <>f 3d. per unit. The proportion of houses already supplied in each city is as follows : —

Wellington. Auckland. Christchurch. Dunedin. Steam . . olas and oil Electric motors .. 4.200 6,000 10,800 21,000 4,800 6.00( i 6,100 Hi.OOO 2,200 3,200 6,600 11,900 2,500 2,200 9,500 14,200 '

Wellington. Auckland. Christchurch. Dunedin. Total mred horse-power Average horse-power for 48 hours per week . . Average kilowatts for 7,200 hours per annum Maximum demand (kilowatts) .. Consumption units per annum Total revenue .. .. .. 10,800 6,100 4,700 2,660 1,230 700 4.500 2,500 8.850,000 ' 5,000,000 £46,000 £26,000 I 6,500 2,840 740 2.700 5,330,000 £27,700 9.500 4,150 1,080 3,900 7,780,000 £40,500

Wellington Auckland . . Christchurch Dunedin .. Total Houses. 15,200 14,802 13.138 13,130 Number Bupplied ,. with BHectrio Light. Proportion. 4,147 28-1 loo 2-7 337 2-9 820 6-2 i