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CONDITIONS AFFECTING THE SUCCESS OF MAIN
W. S. MURRAY,
Member of the Institute.
DISCUSSION MR. ALFRED W. GIBBS (Chief Mechanical Engineer, The Pennsylvania Railroad Company).—While recognizing the merit of the paper and its frankness throughout, I call attention to a few points where it is not sufficiently explicit, or with which I do not agree.
As for the first, I allude especially to the tendency of cities to require electrification through their limits, usually for the purpose of eliminating smoke. While it is true that the inhabitants of a small community may be as much inconvenienced as those of the largest city, it must be recognized that this demand, if fully carried out, means the establishment of as many steam locomotive terminals as there are separate lines of road leading into the city, the alternative to this being the electrification of the whole line. These local terminals would involve not only a heavy capital outlay, but a continued charge to expenses, due to the increased cost of the additional organizations and the less efficient use of the labor and equipment. This is properly a charge to electrification, and a heavy one.
Mr. Murray is not quite fair in his criticism of the engineers who are responsible for the introduction of the direct-current system into the large terminals in New York City. It must be remembered that a long period of agitation had preceded the determination to electrify. The electrification was to avoid the objection to steam operation into the heart of a great city, and the first condition was that it should be a success from an operating standpoint. Is it surprising that the engineers in charge should turn to methods which had been thoroughly tried out? In at least one case the proposal to adopt the alternating-current system of transmission was not seriously advanced until after a very large outlay had been incurred for direct-current operation, * Concluded from page 557, May issue of this JOURNAL.
a large part of which would have had to be absolutely thrown away to introduce the new system—and that untried on a large scale in this country. It must be remembered, further, that any serious operating failure would have jeopardized the whole investment and put back electrification for years. The engineers did not then have to settle the question of future extension of electrification.
There was not then, and there may not be for a long time, any necessity to consider the question of future road electrification. By that time the air will have cleared considerably. It must be admitted that the operating results in New York have fully justified the engineers responsible.
I criticise, also, the statement that one pound of coal burned under the boiler of a central power plant will develop twice the drawbar power that the same amount of coal will produce when burned in a locomotive firebox, Proper allowance has not been made for the improvement in the modern steam locomotive with more liberal boiler capacity and with superheat. As an example, I have a record of coal per drawbar horse-power for 27 tests of one locomotive on the locomotive testing plant at Altoona. It shows: 2.5 to 3 pounds .
12 tests 3 to 3.5 pounds ....
7 tests 3.5 to 4 pounds
3 tests 4 to 4.5 pounds
.................. I test 4.5 to 5 pounds .... .......................... 4 tests These are the rates when running, added to which are certain standby losses at terminals.
The figures for the coal per kilowatt-hour at Cos Cob, as given by Mr. Murray, when reduced to drawbar horse-power for the locomotive, do not justify the statement of relative efficiency.
There is great difficulty in arriving at a fair basis of comparison between steam and electric operation. For road locomotives and through electric operation the problem is the simplest. For switching service, where the steam locomotive may waste more steam at the safety valve that it uses in the cylinders, the problem is very different. This part of the paper covers one of the greatest advantages of the electric operation.
In the table giving the cost of power the total costs are not given. Operation and maintenance account for 0.511 cent; fixed charges, including taxes and insurance, amount to 0.180 cent. No allowance is made for depreciation in the form of obsolescence in the power-house and its equipment. From data of somewhat similar power-houses, I should say that the fixed overhead charge, including depreciation, would be nearly double the figure given, say 0.35 or 0.4 cent, in the inverse ratio to the output. I regard this part of the expense account as a most important part of the accounting; otherwise, the time comes with startling suddenness when you have obsolete equipment, with insufficient reserve to replace it.
While making these criticisms, it is but fair to recognize the courage of those responsible for the electrifications described in this paper and preceding ones.
The paper is, in my judgment, very instructive, and all the more so because no claim is made for the 100 per cent. perfection which we never realize.
MR. GEORGE R. HENDERSON (The Baldwin Locomotive Works).—Mr. Murray's paper on Main Line Electrification will stand out as a “classic,” giving, as it does, actual figures for cost of operation on an alternating-current line. Several years ago Mr. W. J. Wilgus gave similar data for the direct-current lines of the New York Central. Both of these papers show that “uniformity” of traffic is just as important as “ density” of traffic, otherwise the overhead charges of the power plant, which must be abnormally large, will more than “eat up” any saving due to fuel consumption, repairs, and labor, as the plant must take care of peak loads, and these can only be “smoothed out " when the traffic is uniform. As one hundred dollars per kilowatt will hardly cover power-house and transmission lines, the importance of this observation will be obvious.
The fuel saving is stated as 50 per cent. for a fixed drawbar pull, yet it must be borne in mind that this comparison is made with the old type of saturated steam locomotives, and modern steam engines, fitted with superheaters, will reduce this ratio very considerably, say to 65 per cent. the amount of coal for such a locomotive as would be built to-day.
The fact that electric locomotives cost about three times as much as a steam locomotive of similar power must not be overlooked, also the flexibility of service of the latter is very important, as it may be transferred to any division desired owing to traffic conditions, and is not tied to a particular section whose limits are the lengths of the conductors leading from the powerhouse. This is of prime importance to roads carrying intermittent business, such as live stock, which may have a week's work consolidated into a single night, or on the ore ranges in Michigan, which deliver cargoes to lake boats only during the period of navigation. Under such conditions the overhead charges would be out of all proportion to the work accomplished, and the electric locomotives would be idle a large part of the time, as they could be used only on electrified divisions.
However, we are glad to note that Mr. Murray does not wildly and enthusiastically proclaim electrification a “sure cure " for all evils, regardless of environment and operating conditions, as did some electrical experts a few years ago, and the conservatism for which he pleads will surely benefit the whole problem of electrification, by insuring the large expenditures chargeable to capital only where they will produce remunerative returns from operation.
Mr. E. H. McHENRY (McHenry & Murray, Engineers, New Haven, Conn.).—Mr. Murray strikes a very important key-note in the opening paragraphs of his interesting paper, in referring to the two-fold necessity for satisfying the requirements of both the public and the railroad as the touchstone of success.
The first requisite in the interest of the public may be fairly claimed as already satisfied, but the greater task of insuring adequate returns to the railroads upon the large capital investments required for conversion from steam to electric traction is as yet far removed from the state of an exact science. As stated by Mr. Murray, there are many places where electric traction could now be installed with profit, but the ability and ingenuity of the engineers will be taxed to the utmost degree in further widening and enlarging the present commercial field of application. The progress of recent years in the development of the art all tends in the right direction, as with experience and a clearer perception of the governing principles, the commercial efficiency of the invested capital grows greater, and there is no reason to doubt that the past progress will be continued in the future, with the result of greatly extending the present limits. With the growing tendency toward the consolidation of the best features of all the divergent systems into one system of greatest combined merit, the so-called war of the systems is already nearly at an end, and even now it will be found that there is more to be gained by a study of the possibilities afforded by the new method of train propulsion in securing the closest adaptation of its many points of merit to the operating requirements than by any probable difference between rival systems. There is room for much optimism in this general direction, although many cases will arise of special difficulty, in which the community or that part of the public most benefited by the improved facilities are least able or least willing to pay the cost of the service, as in the case of communities using costly passenger terminals, and unless some satisfactory method can be devised for spreading the cost of such service over a city or a state substantially in the form of a tax, no practical solution of this difficult problem will be clearly apparent. In electrification, as in all other branches of engineering, the highest art will be shown by “ the ability to make a dollar earn the most interest.”.
MR. C. RENSHAW (Westinghouse Electric and Manufacturing Company).—As a traveller climbing a mountain will often not realize the height he has attained until, pausing, he looks back over the route he has traversed, so, although from the beginning I have followed the New Haven electrification through its various stages, the summary which Mr. Murray gives of the electric mileage, equipment, and activity to which the road has now attained has impressed me particularly.
The application of electricity to the operation of every class of passenger, freight, and shifting service on an entire engine division of one of the busiest trunk line railroads of the country is an achievement that stands without a parallel in the entire world. It should be particularly gratifying, not only to those who are interested in electrical matters, but to the general public as well, that the undertaking is proving an economic as well as a technical success.
No less notable than the achievement itself has been the policy of the railway company in giving so freely to the engineering public the full results of its investigations and experience, not only with regard to its successes, but—what is of perhaps greater utility and certainly of greater rarity—with regard to its difficulties. The costs and other data which Mr. Murray has included in this paper