POWER AVAILABLE

Nelson Evening Mail, Volume LXXII, 23 November 1938, Page 10

POWER AVAILABLE

REQUIREMENTS IN WAIMEA BOARD AREA SPECIAL REPORT BY ENGINEERS "NOT MUCH TO WORRY ABOUT” The power requirements of the Waimea Electric Power Board to the end of 1539 were reported on fully by the consulting engineers, Messrs Vickerman j and Lancaster, at the board meeting ; yesterday, i The report stated: GENERAL jl "The question of power requirements j naturally falls under two headings: (a) [Power demand and (b) consumption in i units. We have assumed that the board’s j instructions refer not only to the prob- | able increase in these two items during I next year, but also to the means wherei by such increased requirements can be ! met, under the supply arrangements which are or may be made available to the board. "In considering the probable requirej ments of next year, we have reviewed i the general development of the board’s business during the past eighteen months, the increase in the number of consumers, the increased sales of units per consumer by reason of the exten-

sive adoption of ranges and waterheaters, and the effect of these increases on the total power demand, and on the total units to be made available, either by generation or purchase. ‘‘The monthly figures for the period from January, 1937, up to the present are set out in a curve sheet, and the dotted extensions, covering next yeai*, indicate what we think is a reasonable forecast, assuming that the progressive methods now being pursued are continued by the board. NUMBER OF CONSUMERS ‘‘The number of consumers has steadily increased during the past two years, due in part to the extensions in the Waimea area, and in part to general development in the Motueka area. “The figures are: January, 1937, 2,022; January, 1938, 2.219, increase 9 per cent.; October, 1938, 2,632, increase 19 per cent. “A further substantial increase will take place shortly when Wakapuaka, Monaco and other small extensions, and Government houses at Motueka, are connected, and the total will then reach approximately 2,750, after which the rate of increase will slow down until provision is made for the Central area. “To be on the safe side, however, we have assumed that by the end of 1939 the number of consumers may reach 3,000, and we have estimated accordingly. POWER DEMAND “It is somewhat difficult to estimate prospective power demand, as the peak figure varies considerably month by month, depending on the weather and the over-lapping of certain types of; load. The maximum to date is 720 k.w., corresponding to about .275 k.w. per consumer. If supply is unrestricted, as at present, this figure can be expected to increase to. say, .360 k.w. per consumer in the coming year, a value about 10 per cent, above that reached by the Marlborough Electric Power Board. On this basis and with approximately 3,000 consumers, the demand would reach from 1000 to 1100 k.w. Under its tariff, however, the board has the right to restrict the demand in the case of certain industries, and, if this right is exercised, we would expect that the demand would not exceed 1000 k.w. or about 40 per cent, above the present figure.

UNITS PER CONSUMER PER MONTH “The development of the board’s electric supply business is very clearly shown by the increase in consumption per consumer per month, this figure being 56.5 for January, 1937, increasing to 73.4 by January, 1938, and to a maximum of 112.0 for September, falling again slightly last month. “The reduction of the last step of the board’s domestic tariff to Id, coupled with increasing confidence in electric ranges, will no doubt result in the installation of these appliances, together with electric waterheaters, in increasing numbers in the near future. “In addition, a number of industries in the board’s district are coming into production, and these, combined with the increase in domestic sales of electricity, will raise the units per consumer per month by a considerable proportion during the coming year. We have again assumed a liberal figure, 160 units per month per consumer by December, 1939, an increase of 43 per cent, over the figure for September, 1938. This may be compared with 151 units per , month per consumer, the average obtained by Marlborough over the 12 months of last financial year. UNITS PER MONTH GENERATED I AND PURCHASED “The total units per month to meet! the requirements of the board's busi- i ness have shown a more or less steady increase, as the following figures will; indicate: January, 1937, 114,460; Janu-j ary, 1938, 162,760, increase 42 per cent, i September, 1938, 291,260, increase, 79 per cent, in eight months. “‘Based on the arugement set out' above, the units will continue to in-1 crease and by the end of next year, jf! our forecast is realised, will have reach- i eel the figure of 480.000 for the month, I or approximately 65 per cent, in 15 j months. “This figure corresponds to 1920 unils* per consumer per month, as compared with 828 for last financial year, and 668 for the previous year, and no further; comment need be made on this point 1 POWER SOURCES AND LIMITATIONS "The preceding paragraphs, ancl the curves, indicate that by the end of next year the board may have to provide supply up to a demand of 1000 k.w., and a consumption of 480,000 units per month. "With sufficient water available for continuous fall output, the capacities of the board’s plant§ may be set down at: Brooklyn, 250 k.w., 162,000 units per month (maximum to date 155,370). Motueka, 100 k.w., 32.400 units per month (allowing 12 hours per day at 90 k.w.). Brightwater, 150 k.w., 97,200 units per month. Total: 500 k.w., 291,600 units per . month.

“The Stoke plant is rated at 750 k.w., and, to meet the deficiency between the board’s requirements and the units generated by it, the Hume Electric Power Company would be required to supply 183,400 or an average of 7250 units per day for 26 days. The plant is running on this output on two-shift operation at the present time and the service may therefore be regarded as well within the plant’s capacity.

“Under conditions of low water flow, the capacities of the board’s hydro stations must be considerably reduced, and the following are, we think, conservative figures:—

Brooklyn, 250 k.w., 56,000 units per month.

Motueka, 100 k.w., 32,400 units per month, as above.

Brightwater, 100 k.w., 50,000 units per month.

Total: 450 k.w., 138,400 units per month.

“The Stoke plant, combined with the board's plants, would still be able to handle the peak demand, but the hours of working, at least on the 250 k.w. set, would require to be extended to make up the water deficiency at Brooklyn.

“Allowing for two-shift operation on the 500 k.w. set and three-shift on the 250 k.w. set, and an average loading of 80 per cent, capacity on 26 days of the month, the output from this plant could be brought up to 9600 units per day, or 249,600 units for the month. The total provision for the board’s requirements will then be 388,000 units, leaving a deficiency of 92,000 units.

“Low-water periods on the board's plant occur during the summer, when the demand on the Nelson City Council’s steam plant is a minimum.

“While we have not discussed the matter officially with the Nelson City Council, we understand from the informal discussion which recently took place between the chairman of the board and members of the City Council, that suitable arrangements can be made whereby the deficiency, if a reasonable amount, in the board’s supply, may be met from the council’s steam station during periods when their plant would otherwise be relatively lightly loaded. TRANSMISSION OF POWER TO MOTUEKA AREA "As has been previously stated to i | the board, the Motueka and Waimea' I systems are designed for reticulation j purposes, and not for the transmission ! | of relatively large blocks of power from | Stoke to Motueka and vice versa. I 1 “During the early part of next year! j the Hume Power Company’s transmis-1 j sion line will be constructed, and it is i recommended that the company be re- | quested to make this line available to I the board, if required by it, pending the | completion of the Cobb hydro-electric j works. Its use would result in more j uniform voltage over the area, and a j j reduction in transmission losses, and j generally in more satisfactory service to 1 [ the board’s consumers, if it is necessary! j to transmit 400 or 500 k.w. from Stoke! tc the Motueka district. CONCLUSION i "In submitting this report to the [ board, we have, we believe, taken a fairly optimistic view of the probable development of the board's business during the next year. There is no reason, however, to assume that the present rate of increase in sales will not continue, and estimates must oe based accordingly. At the same time, the figures we have deduced for demand and consumption are not such as to warrant any undue anxiety that the position cannot be handled by the present generating plants of the districts. "In preparing this report we have conferred fully with Mr Andrews, as the boax-d’s engineer, and we understand that he concurs with the conclusions we have reached.” “PRETTY SAFE LINES” The chairman, Mr H. E. Stephens, | said he thought that the board members l

would agree that the engineei's hud worked on pretty safe lines in making the estimates. They had allowed for a reduction from 291,000 to 138,000 units if I dry season occurred. In that case the board would have to buy a small quantity of power from the Nelson City Council. "We have not got much to unduly worry about,” he remarked. Mr W. Max pointed out that the estimates took the board up to the end of the extension of time allowed the Hume-Cobb River Company. Mr J. A. Logan inquired what would happen if they were not connected up with the Cobb scheme by then. The chairman said that if by the middle of next year the company wanted another extension they should discuss the position in regard to putting in an extra standby plant. The board would have to watch its position on the chart month by month. If there was any indication of a shortage they would have tc get into contact with the Hume Com- j pany and see if some arrangement could | not be made, either by subsidising a supply from the City Council or by putting in a standby plant. Mr C. B. Webby remarked that as far as the report went it was all right, but they had to trust the weather. It was decided on the motion of the chairman and Mr L. A. Higgins to thank the engineers for the comprehensive report and to adopt it.