D.—l

103

The maximum demand per head of population in the area supplied is 0-105 kw., 70 per cent, of the allocation of 0-15 kw., or 0-2 h.p. per head of population, which is the basis of the design of the Government schemes. The units sold per head of population supplied were 398, as compared with 320 last year_ The total length of distribution-line is 17,759 route-miles, as compared with 17,063 last year, an increase of 696 miles, or 4-1 per cent. The number of consumers per route-mile is 15, as compared with 14-3 last year, the increase being due to the extra mileage of new lines erected during the year and to the increased generating-capacity made available. The maximum power-demand per route-mile is now 8-15 kw., the sales 30,600 units, and the revenue £211. The units are better than last year (26,800), and there is a slight increase in revenue as against £198 last year, and there is an increase in the maximum demand of 6-9 kw., last year. The revenue per kilowatt of maximum load of all stations was £26, as compared with £28-4 last year. The water-power stations show a revenue of £27 per kilowatt, steam stations of £21-97 per kilowatt, oil stations of £37-01 per kilowatt, and gas stations of £44-28 per kilowatt. These are valuable figures for use in forecasting the revenue from systems of various descriptions. The water-power systems include the greatest proportion of large consumers, and the gas-engine stations the greatest proportion of small consumers. Out of the ninety-six scheduled supply authorities, sixty-nine showed a profit for the year amounting to £673,256, and twenty-seven showed a loss amounting to £159,441. The general result is a net profit for the whole Dominion of £513,81.5 after paying working-costs (£1,814,633) and capital (interest and sinking fund) charges (£1,425,793) at the rate of 5-99 per cent, on the total capital outlay of £23,813,228. This shows a net profit of 2-16 per cent, as compared with 2-13 per cent, last year. The business, on the whole, is thus a thoroughly sound and remunerative one, as well as supplying a public necessity to 91 per cent, of the population of the Dominion. The following table summarizes the results of the year's operations in connection with electric supply throughout the Dominion :—

Results for Electric-power Supply of New Zealand for the Year ended 31st March, 1929.

GROWTH OP LOAD. In the early days of electric supply electricity was used almost exclusively for lighting purposes, but with the advent of electric motors and the application of electricity for heating purposes the power and heating load increased, until at the present time the energy used for lighting is small compared with that used for other purposes. The benefits of electric drive in factories and workshops have to a large extent been taken advantage of, and the use of electricity for commercial heating and domestic heating and cooking is rapidly increasing. The use of electric ranges, water-heaters, and portable domestic appliances, such as radiators, toasters, percolators, vacuum cleaners, and kettles, during the past few years confirms the opinion that the use of electricity for domestic purposes will soon exceed the demand for industrial and commercial uses. An interesting graph has been prepared showing the growth of load from 1919 to 1929, and is published with this report. This graph shows the annual increments in the installed generatingcapacity, aggregate maximum demand on the generating-stations, the number of consumers supplied, number of units generated, and total connected load. The figure for the installed capacity of hydro

Water. Steam. Gas. Oil. Total. . * I __J Number of electric-supply authorities .. 88 3 2 3 96 Installed capacity (main plant only), (kilowatts) 146,512 27,324 112 1,016 174,964 Average installed generating capacity (kilowatts) 1,665 9,108 56 339 1,822 Maximum load (kilowatts) .. .. .. 113,360 29,650 87 1,129 144,226 Units generated .. .. .. .. 483,795,760 107,851,325 102,554 3,158,222 594,907,861 Units sold .. .. .. .. 441,182,465 97,471,660 80,623 2,519,316 541,254,064 Annual load factor (per cent.) .. .. 48-8 45-43 13*46 34-45 47*1 Number of consumers .. .. .. 216,811 44,659 448 4,388 266,306 Capital outlay .. .. .. .. £20,584,109 £2,980,555 £22,672 £225,892 £23,813,228 Capital outlay per kilowatt installed (including £140-49 £109-08 £202-43 £222-33 £136-10 reticulation) Total working-costs .. .. .. £1,447,644 £330,555 £3,408 £33,026 £1,814,633 Working-costs per unit sold .. .. 0-79d. 0-81d. 10-14d. 3-15d. 0-81d. Working-costs per kilowatt (maximum) .. £12-8 £11-15 £39-17 £29-25 £12-5 Total capital charges .. .. .. £1,213,066 £199,664 £1,708 £11,355 £1,425,793 Capital charges per unit sold .. .. 0-66d. 0-49d. 5-08d. l-08d. 0-63d. Capital charges per kilowatt (maximum) .. £10-66 £6-73 £19-63 £10-06 £9-88 Capital charges as percentage of capital outlay 5-89 6-70 7-53 5-03 5-99 Total annual costs .. .. .. £2,660,710 £530,219 £5,116 £44,381 £3,240,426 Total costs per unit sold .. .. .. l-45d. l-30d. 15-22d. 4-23d. l-44d. Total costs per kilowatt (maximum).. .. £23-46 £17-88 £58-80 £39-31 £22-38 Revenue (not including rates) .. .. £3,057,335 £651,273 £3,852 £41,781 £3,754,241 Revenue per unit sold .. .. .. l-66d. l-60d. ll-47d. 4-00d. l-66d. Revenue per kilowatt (maximum) .. .. £27-0 £21-97 £44-28 £37-01 £26-0 Net profit.. .. .. .. •• £396,625 £121,054 -£1,264 -£2,600 £513,815 Ratio of working-costs to revenue (per cent.) 47-35 50-76 88-47 79-05 48-34