STREET LIGHTING

Press, Volume LXX, Issue 21147, 24 April 1934, Page 8

STREET LIGHTING

INTRODUCTION OF NEW TYPE

CITY'S SYSTEM REVIEWED

KICCARTON AVENUE SELECTED

Eiccarton avenue, from the Public Hospital to Deans avenue, will be lighted with the new gaseous discharge lamps; the process in operation in residential areas of improving the worst cases will be continued with filament lamps; further consideration will be given to a suggestion that the new lamps be installed at the Bank of New Zealand corner and at the corner of Armagh stree{ and Colombo street; lighting of Papanui road, and other considerable main thoroughfares will be considered on the basis of replacement of the present 100 candle-power lamps with 250 candlepower lamps; half the annual cost of such improvements to be met by a reduction of £9OO a year in the present street lighting charges. These decisions were made by the Christchurch City Council at its meeting last night after long consideration of a report on street lighting which was the outcome of the demonstration of tho new lype of gaseous discharge lamp on Papanui road during the second week of last month. The report was prepared by Mr E. Hitchcock, general manager of the municipal electricity department. The demonstration of the gasous discharge lamps, which aroused so much public interest when given a trial on Papanui road from Beaiey avenue to Merivale Jane, was under the direction of an officer of the municipal electricity department and with the co-operation of the representative of the British General Electric Company. Three types of lanterns were tested. I

Report of Demonstration In his report for the demonstration Mr Hitchcock stated:— "The lamp used in each of these lanterns has a useful life of 1500 hours. The candle-power is approximately 1600. The two directional fittings are arranged to throw GO per cent, of the light along the highway in the direction in which the traffic is travelling, and only 31 per cent, in the opposition direction. The fittings were erected at a mounting height of 25 feet and a spacing of 200 feet. Nine lamps were used, three undirected over the centre of the roadway. and six with directed lighting on the poles on alternate sides of the road. The spacing recommended by the British General Electric Company was 150 feet. but this could not be obtained as the existing poles were not suitably spaced, and a spacing of 200 feet was therefore adopted. The _ existing lamps arc mounted at a height of approximately 25 feet, and spaced approximately 300 feet apart, being plain i suspension fittings with 100 candlepower lamps. The price of the new lamps and lanterns, apart from any mains, switch-gear, or transformer equipment, varies from £2O to £24 for (he directional fillings, and about £l2 for the plain fitting. The cost of the existing lilting is £2, and ot the lamp 3s Id. "On Ihe prices gUeii and the present, basis of annual charges, the cost per annum of the new lamps would be approximated" £lO each," the report continues. "The new lamps are suitable only for parallel operation, and coidd not therefore be supplied front the city's street lighting system. Supply had to be taken from the ordinary street mains. This necessitated separate control. The cost of the demonstration to the department was £22. As was to be expected with the extreme increase in candle-power and the closer spacing, the demonstration lighting was an overwhelming improvement on the existing lighting. The uniformity of illumination was a marked feature. The centrally-hung lamps without refractors were not as effective as the staggered bracket lighting with elongation effect. The abnormal colour effect was another marked feature. There was a good deal of adverse comment on this aspect. It. would certainly not be a merit in city lighting. The single unit was erected at the intersection of Montreal street and Worcester street as requested. The British General Electric Company advise strongly against the use of this lamp in single units. Tnis recommendation can be understood in that it would obviously be distinctly misleading and would not serve any really useful purpose merely to demonstrate the pronounced difference between a 1600 candle-power lamp and a 100 candle-power lamp. Sudden changes from extreme brilliance to normal lighting within the economic possibilities would not be good practice. > "Welcome Advance in Lighting "The demonstration, like all such demonstrations, shows that the first practical examples of a new discovery are inevitably attended by certain limitations and disabilities, but the chief feature and significance lies in the very welcome and impressive fact that another marked advance has been made in illumination efficiency. It is but a few years ago that the normal filament lamp required four or five watts of energy to produce one candlepower of illumination. It was considered a great advance when lamps were made which required only two watts of energy a candle-power. The one-watt lamp was a still further ad-\-ance, and when gas-filled lamps made it possible for only one half-watt of energy to provide one candle-power of light, the half-watt lamp was hailed as a great advance. These new lamps lor each one watt of energy consumed are yielding approximately four candle-power. When this discovery comes to its fully proved and tested development, it must inevitably have? a far-reaching effect upon ideas and; standards of lighting." I Relation to General Problem The bearing that the demonstration had on street lighting generally Mr Hitchcock made the subject of a separate report:—ln it he stated that the following points were unaffected by the demonstration:—(l) The ultimate character of the problem was financial: (2) arbitrary selection of locality for improvement would have to be made (3) residential streets required consideration apart from the new type of lamp: (4 )smaller units at closer spacing were desirable, especially in residential areas:; (5j any substantial increase in lighting required provision of mains capacity, transformers. and switch gear: ((j) additional amount of annual expenditure would govern amount of new equipment secured.

Arising from (he demonstration Mr Hitchcock raised the following points: (1) The demonstration could not help providing an extreme and dramatic contrast. It would have been possible for the council to have arranged a similar contrast at any time apart from the new type of lamp. (2) The colour effect was excused rather than recommended. (3) In the same field of lighting there was evidence of keen trade competition and it was probable that, the lamps would improve in characteristics and probably in price. One company already claimed elimination of

the colour defect. It might be desirable to await, demonstrations of other lamps also. (4) The lamp was suitable for parallel system while the street lighting at present was of a series type. (5) The use of single lamps had definite disabilities; an isolated patch of peculiar light of high intensity would have dangers. (6) The extreme jump from 100 i candle-power to 1000 candle-power 1 was difficult to justify. An improvej ment of less magnitude could be made i at much less annual cost. i (7) The new lamp had captured j popular imagination and the city's ! "up-to-dateness" would be judged by I some in terms of its adoption of the new lamp. In a public utility that could not be eliminated from consideration. (8) The case for stronger street lighting grew as motor traffic increased. . , . It was suggested that in making a decision answers would have to be given to several questions. The demonstration illustrated the last word m -treet lighting for the highways of older countries carrying dense traffic. To what extent should it be considered and made a basis of compaiison for Christchurch requirements? Could the city afford to increase a portion of an annual burden to be abnormally lighted? Was it wise to adopt immediately the first commeicial product of a new development? Was not the public interest aroused by the demonstration a desirable opportunity to secure approval for increased annual cost to provide a necessary increase in the city lighting?

| Suffffcstiom for Improvements The report concluded with the following suggestions: (1) That Riccarton avenue be lighted with the new lamps. Twentyfour lamps would be required, involving an approximate annual cost Of £3B4 ' , ' Koi^r, (2) That the process alreauv bein„ carried out in residential areas of steadily improving the worst cases, be Continued systematically. It is recognised that the gaseous discharge lamp will not. for a long time, replace the filament lamp. The ial'.er must, of necessity, continue to Lx: used for suburban .streets. C.i) That in spite of the undesirabuity of some patches of intense illumination,, consideration should be given to the bank corner and the corner of Armagh and Colombo streets, as possibilities for the application of the new lamp. t4) That in the m:antim_> the lighting in Papanui road and other comparable main thoroughfares be considered on the basis of replacing the present 100 candle-power lamps with 250 candle-power lamps—the extent to be determined by expenditure authorised, plant capacity, and other controlling factors. (5) That some pro rata improvement be effected in the area bounded by Rolleston avenue, Colombo street. Armagh, and Cashe! streets, either by respacing or by increase of candlepower. <C) Consideration has been given by the council to an increase of £2OOO per annum in the city street lighting. As part of the detailed examination of the whole street lighting problem, the present, street lighting charges have been carefully reviewed. There are several respects in which possible adjustments are suggested, and it is recommended that a 10 per cent, reduction be made in the present street lighting charges. This represents approximately £9OO per annum. The proposed annua) increase in the amount of street lighting could therefore be carried out, and practically half the annual cost met. by the reduction in charges now recommended.

Council's Discus ion In moving Ihe adoption of the report, Cr. E. R. MeCombs, M.P., said she wished to dissociate herself personally from some of the proposals of the report. although it was her duty as chairwoman of the committee to present it. Riccarton avenue had been selected for the new type of lighting because it. was a type which would not blend with the general lighting of Ihe city. 11 might be confusing for motorists io drive from one type of light to another. Other firms were inventing lamps that did not have the disadvantage of colour of those demonstrated in Christ church. She thought street lighting should be a charge on the ratepayers and not a burden on the users of electricity, who were already paying the;r fair share of street lighting. Cr. T. Millikcn moved as an amendment that the report be adopted with the exception of that clause recommending that the new lights be installed on Riccarton avenue. He thought the lamps were still in the experimental stage and that it was too early to install them. Cr. W. Kayward seconded the amendment. Cr. F. T. Evans supported the whole of the report as unproved street lighting was needed by all road users. He thought the proposed reduction or £9OO a year an excellent one, and that the Bank of New Zealand corner and Cook and Ross's corner should be well lit by the new lamps. Cr. E. H. Andrews said the estimated life of the lamps was only 1500 hours. At eight hours a night they would not last 200 nights. What did it cost to replace them? The general manager of the Municipal Klcctricity Department (Mr Hitchcock) said the life of the normal lamps now in use was 1000 hours. Part of the annual cost was the replacement cost, and replacements were allowed for in the estimated annual cost of the new type. A street light was estimated to burn 3600 hours a year. The present replacement cost of the new type was £2 12s, but no doubt that would improve. Cr. M. E. Lyons said he believed that if a plebiscite were possible, 90 per cent, of the population would say the street lighting of Chrislchurch was antcdeluvian, and he believed that a change would be well founded. The council should experiment, and see wnat effects it could got. Here was an opportunity and the council should seize on it. Cr. J. K. Archer suggested that Ihe report be referred back for further consideration. He thought a demonstration shouhl be given in some place where it could be seen, not in the backblocks of Riccarton avenue. He appreciated the report, but it was a dif- ! ferent thing to adopt ail its recommendations. He thought the demonstration could well be given in Cathedral square, or in a section of Colombo street. Cr. Hayward said he thought it was dangerous and unwise to put the lamps, which provided intense illumination, at any particular corner Heagreed with Cr. MeCombs that they were going ahead 100 iast. Clauses Passed J ; Clauses two. three, lour, and five! were then put to the council and i passed. ; 1 Discussing clause one. the Mavor' (Mr D. G. Sulivan, M.P.) askeil "the council to decide first whether an experiment should be made at all, and if so, where'.' Gi. O. 1. Thurston said all the proposals were to be paid for by the saving of £9OO recommended "in clause six. The replies of the general manager showed that the lamps were suited to highway lighting rather than for an isolated spot. There were alreadv 35 lamps of 100 candle-power each in Cathedral square. Cr. Lyons said Riccarton avenue had been more or less deliberately selected on account of its nculralilv He thought it would be dangerous to put the lights in a business area. The Mayor thought that a city of the size and importance of Christchurch should be prepared to assist in some measure in such an experiment. Cr. MeCombs said the charges for street lighting were reckoned just about to cover the cost, Generally speaking, Chrislchurch had cheaper street lighting than any other city in New Zealand. The council decided by eight votes to six that a experiment be made, and by 11 votes to three that it bo made in Riccarton avenue. The voting on the first issue was: Ayes, Crs. Butterfield, Barnett, Thurs-