Electric tramway

“ Dismissing all these systems, we turn to electricity, as admittedly the best agent for tramway traction, and, until some marvellous discovery displaces it as a force, likely to remain and to become universally adopted.{132}
Blackpool was first in the field with an electric tramway in 1883. Several other provincial districts followed suit, including Bristol and Stockton-on-Tees. London, in 1900, welcomed the completion of Mr. J. Clifton Robinson’s great scheme for electrifying that portion of the London United Tramways running between Hammersmith and Kew. ”

“ A regenerative tramway may thus be represented, from the energy point of view, as one in which all the cars are running at normal speeds on level roads.
Incidentally the regenerative system gives a very perfect control of the speed of the car on all gradients, owing to the regeneration which begins automatically when the motors start 'coasting.' It is a power-saver and a brake in one; and its efficacy as a means of control is so great that, if its incidental drawbacks could be avoided, it would be worth adopting for this purpose alone, both on electric tramways and on electric railways. ”

“ But with electric traction the main item is the cost of the standing equipment—the power house, [Pg 26] mains, and overhead lines—and unless that equipment is adequately utilised the revenue will not cover the standing charges. A fifteen-minute service is, generally speaking, the lowest economic limit on an electric tramway. Every tramway manager tries to attract sufficient passengers for a more frequent service ”

“ ELECTRICITY IN LOCOMOTION The electric tramcar has become such a necessary feature of our everyday life that it is very difficult to realize how short a time it has been with us. To most of us a horse-drawn tramcar looks like a relic of prehistoric times, and yet it is not so many years since the horse tram was in full possession of our streets. Strikes of tramway employees are fortunately rare events, but a few have occurred during the past two or three years in Leeds and in other towns, and they have brought home to us our great dependence upon the electric tram. ”

“ The higher speeds with more frequent, more comfortable, and more commodious cars have created a volume of traffic far beyond what could have been handled with horse traction. The change also led to a great increase in the length of tramway routes and to the construction of new tramway systems. In 1898, when the electric tramway movement began in earnest, there were 1064 miles of tramway in the United Kingdom. Now there are 2562 miles, and the number of tramway passengers is more than double the total of third class passengers on the whole system of British railways. ”

“ At one stage, no doubt, people were a little too enthusiastic about electric traction. They imagined that electric traction would create profitable traffic along the most deserted of side streets. Acting on that theory, municipalities constructed—or forced tramway companies to construct—lines along roads which could never supply [Pg 58] enough traffic to justify the expenditure involved. The interest on capital and other standing charges for an electric tramway route are so substantial that a certain minimum of traffic density must exist before any profit at all can be earned. ”

“ Pending that revolution, tramway authorities are seeking to develop a cheaper means of electric traction than the tramway. At the present stage, urban tramways have spread through suburbs towards villages and small towns which are anxious for better transport facilities but have not sufficient population to justify a tramway extension. Inter-urban tramway systems—those connecting towns with a network of lines—are also adjacent to such minor centres of traffic. ”

“ A further rival to the electric tramway is arising in the system of railless electric traction, the fundamental principle of which is the application of electric power, derived from overhead wires, to electric cars, resembling motor-omnibuses (or alternatively, to goods lorries and vans) , driven on ordinary roads without rails, and capable of being steered in and out of the traffic over the whole width of the roadway. ”

“ Existing tramways can be adapted to this system with rapidity, and all experts bear testimony to the fact that electric haulage is comparatively so cheap, and the development of traffic on its adoption so great, that horse traction has no chance against it.
There are four kinds of electric-tramway traction which, though apparently rather puzzling, are readily explained. These are the Conduit; the Surface Contact; the Overhead (or trolley) ; in each of which the{133} current is conveyed to the line—as in an electric railway—from a power house ”

“ Along the Boulevard Andrassy at Buda-Pesth there is a shallow electric tramway built upon similar principles, a few feet under the main thoroughfare, which is by no means a failure, financially or otherwise. ”

“ If, in the result, private enterprise, thus driven to adopt new expedients in locomotion, should so far perfect a motor-omnibus, or any other alternative service, that the electric tramway will not only have a powerful competitor but be largely superseded, the position of the municipalities which first sought to exclude or to exploit private enterprise and then invested large sums in speculative tramway undertakings of their own will be sufficiently serious. ”

“ The engines used to produce this are of 16,000 h.p. capacity, while each of the generators is of the great weight of ninety tons, almost the largest in existence for traction work.
Altogether, the tramway enterprise of Glasgow is in its magnitude and its good management almost unique. The size of its power-house will be surpassed by that which supplies the Electrified Metropolitan District Railway; but the wise and economical arrangement of its traffic can hardly be beaten, and is a model to other large cities and towns contemplating the adoption of electric tramway traction. ”

“ Some of these were promoted by local authorities, one or two were by tramway companies, one was by an omnibus company, and the remainder were schemes by various private promoters.
Municipal corporations already owning and operating tramways would seem to favour the railless electric traction system because it enables them (1) to utilise to greater advantage the electric power they are already generating for tramway purposes; and (2) to provide transport facilities for parts of their district where, as is said, the traffic prospects would not warrant the laying of a tramway. ”

“ It is not generally known that the country people along the line of the electric railway make strange uses of the insulated rails, which are the medium of electricity on this tramway, in connection with one of which an extraordinary and very remarkable occurrence is reported. People have no objection to touch the rail and receive a smart shock, which is, however, harmless, at least so far. ”

“ The motor-omnibus requires no special track, no overhead wires, no power station and sub-stations, and no costly widenings of streets and roads or rebuilding of bridges. Consequently, the capital expenditure involved in the provision of a large stock of motor-omnibuses is far less, in proportion, than that entailed by electric tramways providing an equivalent service. The motor-omnibus, too, has greater freedom in a busy thoroughfare—and is thus quicker in its movements—than the tramway car, limited to a fixed track and much more liable to be detained by blocks of traffic. ”

“ The general conclusion to which these experiments bring us is that, undoubtedly, if it could certainly be relied upon, the electric car would be the preferable form of tramway motor in towns, because it is simply a self-contained ordinary tram-car, and in a town the service requires a number of separate cars, occupying as small a space each as is compatible with accommodating the passengers, and which follow each other at rapid intervals. ”

“ The advantages of accumulator traction, apart from the saving in first cost, are the absence of obstruction and danger from overhead wires, and of the risk of a general stoppage of the service when the current at the generating station fails from any accidental cause. When accumulators are used, the conversion of a horse tramway to an electric tramway becomes a very simple matter. All that is required is to erect a generating station and provide each car with a storage battery and electrical equipment. ”

“ These are entirely, or almost entirely, electric, and have certainly, if we are to judge by the patronage accorded to them, been very favourably received by the Japanese people. According to the latest returns I have available there were twenty-two tramway companies in Japan, which between them, in the year 1904, carried the very respectable total of over 73,000,000 passengers. All of these lines save one are electric. The first electric tramway, that in Kyoto, was opened in 1895, so that the development of the country in this direction has proceeded rapidly. ”

“ The electric tramway, while having to keep to a certain route, and involved in greater capital expenditure by reason of its need for rails, overhead wires and power stations, may, if owned by a local authority, still be materially aided, directly or indirectly, out of the local rates. ”

“ The first thing which strikes one about the trolley omnibus in comparison with the electric tramcar is the cheapness in first cost. All the expense of concrete foundations, heavy rails, and granite paving [Pg 62] is avoided. On ordinary roads the overhead construction is much less costly, as a single line of poles supporting two wires is sufficient for the up and down services. Estimates show that the equipment of a mile of roadway on this system will cost only from one-fourth to one-third of the corresponding tramway system. ”

“ There is no separate locomotive, the motor-dynamo being on the car itself. In 1882 Messrs Siemens constructed an electric tramway in the mines of Zankerode, in Saxony, and built for it a locomotive able to draw 8 tons at a speed of 71/2 miles an hour. Overhead conductors were employed, consisting of a pair of insulated I-shaped rails fixed to the roof of the workings; the current was conveyed to and from the locomotive by means of a pair of contact carriages sliding on these conductors, and connected with the car by short flexible cables. ”

“ A high average speed with numerous stops was, however, only one of the improvements which the public derived from electric traction. Tramway passengers expect to find a car not only at a convenient point but within a convenient period of waiting. With electric traction the service became much more frequent than with horse traction. It is quite possible to run a horse tramway service profitably with cars at intervals of fifteen to thirty minutes, if the passengers are patient enough to wait and fill each vehicle. ”

“ The increase of traffic brought with it the demand for larger as well as speedier cars with a shorter 'headway' or interval between one car and another. The capacity of a horse car is limited by the fact that it is not convenient to harness more than two horses to a single vehicle. But with electric cars there is no extraneous limitation to carrying capacity. Large double-decked cars with seats for seventy passengers are now quite common. In America it is a frequent practice to attach 'trailers' to the cars, making a short tramway train. ”

“ Electric tramways have reached a period of middle age in which they are more concerned about their internal economy than the prospect of enterprise in new directions. Such development as they feel capable of making under present legislative conditions is only by proxy and tentatively, with the aid of the trolley omnibus. ”

“ From time to time attempts have been made to meet the demand by means of petrol omnibuses, but they have rarely been successful—partly, no doubt, owing to the difficulty of working a limited petrol omnibus service economically at the extremities of an electric tramway system. ”

“ Apart from such a large project as the electrification of the District and Metropolitan Railways, there is scarcely a municipal authority in Great Britain which has not in hand some scheme of electric railway, tramway, or lighting. It is as well to think that electricity is not the agent of the future, but of the present, and an era which has already dawned. ”

“ Except in very small tramway systems, the power is generated as high-tension alternating current, and transformed and converted at substations suitably placed in the area covered by the tramway (see Electric Power Transmission and Distribution) . The low-tension D.C. power is distributed from the substations to the trolley wire. The car rails are earthed, and provide a return path for the current. In order to minimize the flow of current to other conductors in the vicinity of the car rails, copper cables returning directly to the substation are connected to the rails at suitable intervals. ”

“ Time is the vital element in all transport, and it is especially vital in connection with tramways, which have to stop with great frequency. If the time which elapses between putting on the brakes at each stop and getting up to full speed again can be materially shortened, then the average speed of the tramway journey can be materially raised. It is easy, by means of powerful brakes, to bring a car to rest quickly; the electric motor enables speed to be regained quickly. ”

“ The American manufacturers and tramway companies, in their keen competition with one another and perfect freedom to compete on even terms with horse traction, soon took the lead in all matters pertaining to electric traction, and the British public, at the close of the nineteenth century, have had to witness the humiliating spectacle of their own public [Pg 280] authorities being forced to import electrical apparatus, and even steam-engines applicable to dynamos used for tramway purposes, from the other side of the Atlantic! ”