THOMAS M. C. MARTIN

AS the title of this article indicates, I am an incorrigible believer in railway electrification. I should like to indulge in the rather human trait of looking backward wistfully. My thesis is that at least some railroads erred grievously in embracing 100 per cent dieselization so quickly after World War II. The reciprocating steam locomotives which had served with distinction for over a century were unquestionably ticketed for retirement. I would agree that locomotives utilizing electric motors for traction were the most logical replacements. The point of departure is the question of where the electricity to run these traction motors is to be generated. A modern diesel-electric locomotive and an equally upto-date straight-electric locomotive are nearly identical in many respects. They can and do use precisely the same type traction motors. Their running gear and controls are quite similar. Electric energy for the diesel comes from a direct-connected generator which, together with its liquid petroleum fuel supply, must be packed along as dead weight. The straight-electric locomotive through its pantographs and a trolley system is connected to central station generators. The latter may be parts of large systems embodying hydroelectric and/or thermal-electric sta

tions and before long will include substantial amounts of nuclear-based energy as a primary resource.

The first cost of a section of railroad supplied from central stations must always be greater than if it were operated with diesel locomotives, since trolley must be provided and some changes effected in communication and signal systems. There is the counterbalancing fact that the fully electrified section costs considerably less to own and operate. In my further remarks I shall confine myself to freight operations. Passenger movements will be disregarded, since there seems to be some doubt as to their permanency. I believe that I can establish a case for mainline electrification on the basis of freight traffic. Should passenger traffic survive or even revive it could only add to the economic justification for electrification.

With respect to operating costs, the advantages accruing to locomotives operating with central station electricity arise chiefly in three ways: (1) locomotive running repairs; (2) locomotive depreciation charges; and (3) the cost of electricity vs. diesel fuel. It is now fairly well established that, taken over the normal service life of the locomotive, approximately one-half of all running repairs for diesel-electrics are chargeable to their prime movers. This means that trolley-fed locomotives of equal normal continuous tractive effort will cost about one-half as much for running repairs. It is also evident that in

creasingly accelerated obsolescence promoted by their automotive-oriented sponsors is necessitating an upward revision of depreciation charges for diesel-electric locomotives wherever conservative and realistic studies of alternatives are made. Finally, there have been, and possibly are, situations where central station electricity can be purchased at some advantage over that produced on locomotives with relatively small power plants. Quite mistakenly, it has been assumed that a railroad must either electrify or dieselize all the way. These, however, are not mutually exclusive alternatives. It is neither necessary nor wise to erect trolley over all kinds of track. The wise course is to combine the two types of motive power after careful study of relevant operating and financial factors have disclosed the proper proportions of each to be included. Generally speaking, only mainline tracks with a reasonable freight-traffic density would be electrified. Branch lines and yard operations would be handled with diesels.

Effect of electric power rate schedules

Soon after the close of World War II the United States Department of Interior through one of its agencies, the Bonneville Power Administration, established a special electric power rate schedule for direct sales of power to railroads for traction purposes. This schedule which

required and received the approval of the Federal Power Commission was the culmination of a four-year study by Bonneville Power of the engineering and economic factors involved in developing industrial markets for excess energy available at the great Federal projects on the Columbia River and its tributaries. The interest of the Federal Government, among other things, was in discovering ways of saving our rapidly diminishing natural resources such as petroleum while also reducing to a minimum wastage of potential hydroelectrically generated energy through forced spilling of water for want of power markets.

This special rate schedule for railroad electrification was unique in the annals of public utility practice in this country. It not only offered electric energy to railroads at the lowest price ever, but it dealt more sympathetically and realistically with their needs so far as the practical operation of motive power was concerned. One of the most profound deterrents to railroad electrification, the demand charge, was eliminated from this schedule. This highly restrictive element in most railway power contracts had long been the best tool in the sales kits of diesel promoters who quite correctly pointed out that their motive power suffered from no such limitations. The electric demand charge, if applied by analogy to the use of diesel fuel, would mean that you couldn't know how much your fuel had cost per gallon until you reported at

the end of the month the maximum consumption in any one of the 1460 clock half hours during the average month. In other words, railroads would have to pay not only for total quantities of fuel burned but also on the basis of how fast they burned it. This is not to argue that the reasoning back of the electrical demand charge is not legitimate. It is generally levied by power suppliers to cover their fixed costs such as capital investment, interest, depreciation, and taxes, while the energy charge is to reimburse for operating expenses such as labor, fuel, and ordinary maintenance. With most industries the usual demand and energy charge schedule operates to "civilize" the industrial customer by discouraging him from "peaking" his use of energy and encouraging him to level off his demands. In the jargon of the trade, he is stimulated to improve his load factor. But railroads are also public utilities, and unlike some industrial consumers, they cannot manipulate their demands widely. Freight traffic largely determines the magnitude of peak power demands by virtue of the exact time maximum tonnage trains happen to climb ruling grades. This freight is offered to railroads as common carriers in accordance with the desires and practices of shippers and in the long run must be handled to suit the latter's requirements. Transportation is now a very competitive business.

Bonneville, in its study of the problem of attracting railroad loads, discovered that, at least in the Western United States, there was a considerable natural variance in the scheduling of freight trains. While some traffic was moved on more or less fixed schedules, a great deal more was handled by means of extra trains which were run whenever sufficient tonnage accumulated at the various terminals and principal classification yards. Careful analyses of thousands of dispatcher's train sheets revealed the fact that had these railroads been electrified, the average monthly electrical load factor would have been quite satisfactory from a power supplier's standpoint. In the language of the electrical engineer, there was a substantial natural diversity in railroad electrification. Because of this research, conducted from the viewpoint of a possible user, Bonneville reasoned that the Government could accomplish the basic purpose of the demand charge and still not alienate all railroad train dispatchers and yardmasters. One Western private utility which in the beginning had started with very restrictive load-limiting devices and rate schedules had substituted a fixed annual mileage charge together with an energy charge for service to its railroad loads. The basing of a fixed charge on the number of route-miles electrified did not seem as relevant a method as the imposition of a simple minimum bill. Bonneville's rate schedule called for a straight energy charge of 4 mills per kilowatt hour of net energy delivered. It was provided that contracts for service under the schedule would specify a minimum monthly bill based on the normal continuous capacity which the railroad requested at its points of feed.

By this means, railroad managements, it was hoped, could be freed of fears that the use of central station power would be less flexible and their costs of doing business more uncertain than when diesel locomotives were used. At the same time, as evidence submitted to the Federal Power Commission showed, the Government could sell power to railroads and earn a return on its general and special investments required to serve them quite as compensatory as revenue provided by rate schedules applicable to more conventional industrial customers. In summary, this railroad rate schedule was merely an attempt to reconcile the interests of power suppliers and power users that were really not adverse but only seemed to be so by reason of the semantics of power contracts and rate schedules.

Electrification opportunities

in the Pacific Northwest

To return to my main thesis, this rate schedule was something "new under the sun." Here was a really matchless opportunity for at least five mainline railroads in the Bonneville service area to enter into long-term contracts that could have assured them of low-cost energy for many years. It is believed that among them these five railroads could have found use for this power on about 2000 miles of their main lines. This was not all. The Department of Interior in December 1946 held a departmental conference on Western railroad electrification. Although its petroleum advisers were unimpressed and entirely negative, the Bureau of Reclamation, a sister agency of Bonneville, expressed some interest in adopting the form of Bonneville's schedule if not the substance. The feeling was that Bonneville's energy rate could not be met. A rate of about 7 mills per kilowatt hour seemed more probable. Had such additional incentive been added to the picture, it is conceivable that 6000 miles of additional Western main line could eventually have utilized central station power from the Government's resources. The Bureau's facilities in point of time would not have been available as early as Bonneville's. In fact, some of them are only now beginning to reach a stage where railroads I could be served.

In the Pacific Northwest all five railroads were made aware at the executive level of this new rate schedule. In addition, various studies and reports were offered to the motive power departments in an effort to stimulate interest. Needless to remark, none of the efforts bore any fruit and those who had pursued this will-o'-the-wisp were relegated to the dustbin.

Private enterprise is endeavoring to prove its right to survive as the entrepreneur of the nation's railroads. One of the cardinal principles of engineering economics would seem to be that when alternative levels of capital investment are required to perform the same task, the prudent entrepreneur must do more than merely choose the alternative requiring the least initial investment. If he plans to stay in business he must give more than passing attention to alternatives that give promise of lowest longterm operating costs.

In 1946 it was pointed out to these Pacific Northwest railroads that with this new rate schedule in existence there also existed a possibility that certain sections of railroad could be electrified with a very high probability of early payout for the additional capital investment required. The arguments were these:

1. These railroads had already decided to retire steam locomotives as fast as possible.

2. Physically and financially diesel-electric locomotives were attractive replacements.

3. Physically the straight-electric locomotive was an even better replacement.

4. Financially electrification cost more initially but not as much more as diesel proponents contended.

5. On an equated traffic basis the annual operating costs were enough less for full electric operation to amortize the extra investment required in not more than 15 years.

The cost of diesel fuel utilized in these studies was about 51⁄2 cents per gallon delivered on locomotives. That the then existing economic margin favoring electrification could widen was pointed out to railroads. Two principal factors were cited that could break the contest wide open. The first was the cost of fuel. It was underscored that the energy source to which these railroads were almost inextricably tying themselves was a "middle distillate" which came from the same portion of the petroleum bar

rel as that utilized by the nation's growing heavy commercial highway vehicles. The then barely visible jet age to come also was to be fueled from this same source. The fact is that diesel fuel has long since reached a figure of approximately 10 cents per gallon on locomotives.

The second factor they were urged to examine more critically was the cost of locomotive running repairs. At that time, and even until recently, the entire subject of diesel locomotive running repairs has been beclouded with a certain amount of pettifoggery through the bookkeeping device of merging repair costs for new units and old units into a mélange figure for entire rosters which completely obscures the rise in costs with age of units. When more care is exercised and costs are kept by age groups, it is now clear that the statement made earlier is a correct one. On an equated tractive effort basis the costs of maintaining a diesel-electric locomotive and a straight-electric locomotive are as 2 is to 1.

Speaking only of these 2000 miles of railroad in the Pacific Northwest that might have been electrified but weren't, it is now evident that an outstanding opportunity went "over the dam," to use a lowly pun, but one that is more than a little apropos. The economics of this case history in lost opportunities works out as follows:

1. The change from steam to diesel operation of these 2000 miles of main line, had it occurred in 1947, would have cost about 60 million dollars.

2. To have electrified these same operations in 1947 would have cost about 120 million dollars.

3. Assuming identical traffic, the electrified portions would have saved about 7.5 million dollars annually in operating expenses, again based on 1947 dollars.

4. It is readily apparent, therefore, that instead of the 15 years for amortization of the extra investment in electrification that had been envisioned in the Bonneville studies, it could have in fact been accomplished in about 8 years.

Conservation possibilities of electrification

The contribution to natural resource conservation which this relatively minor amount of railway electrification would have made may not impress an oil man but the amounts sound big to an electrical engineer. To operate these 2000 miles under the assumed traffic would require 125 million gallons of diesel fuel per year. In the nearly 15 years this has been going on, some 1.875 billion gallons could have been saved for other purposes which are not as susceptible of replacement with central station energy. A railroad is actually one of the few places such a shift in energy base can be accomplished.

The interesting corollary is that in many of these years it would have been possible not only to save 125 million gallons of diesel fuel but also to "save" an equivalent energy in kilowatt hours. What goes on here? you ask. The answer is that when the water which could generate this much energy must be set free over the spillways of hydroelectric projects because there is insufficient demand for the product of their generators, this also is a waste of natural resources. This is one measure of the national disservice for which an insufficient concern with the development of potential markets for surplus power is also somewhat responsible.

In the Pacific Northwest, the Federal Government's Columbia River projects have been spilling energy in this way recently owing in part at least to short-sighted marketing policies of recent years. Apparently this situation is likely to continue for a number of years unless something drastic is done to find indigenous markets or unless a tie line is built which can save this waste through the export of surpluses of both prime and secondary power to California where a population explosion, to em

ploy the cliché of the decade, seems to promise unceasing demands for both water and electricity. This, then, is not an inspiring story either of conservation of natural resources or of private enterprise girding for survival in the field of railroad operation.

Comes the diesel-hydraulic locomotive

At this point the reader may ask about the new dieselhydraulic units being tested by two of our Western railroads. Will not a satisfactory performance by these locomotives set back the cause of railway electrification once more? May not, as happened 15 years ago, the dreams of electrification advocates be lost in new clouds of diesel exhaust? One would be optimistic indeed to presume that the follies of an earlier generation will never be repeated. We seem at times to embody a positive genius for repetitive error. Where the economic choice between alternative levels of capital investment requires courage and a willingness to take the long-term view, we more than occasionally content ourselves with extremely conservative short-term solutions.

These new West German locomotives are the largest units of their kind thus far built. They continue a trend in evidence for some time in European motive power circles. Arguments made in support of these units, if substantiated by the tests now under way, could suggest rather eloquently another go-around by the diesel manufacturers with complete replacement of existing diesel-electric units in service in the United States as the objective.

What are the principal contentions made on behalf of these new diesel-hydraulics? One claim is for greater working adhesions. Another, they are supposed to deliver more useful tractive effort per ton of locomotive weight. The former, if true, would justify assigning increased tonnage ratings to these locomotives per ton of weight on drivers. The second characteristic, also if true, would enable these locomotives to produce more gross ton-miles trailing per train-hour per ton of locomotive weight. Continuous adhesion limits

Taking up first the factor of adhesion: Practical experience has served to limit the maximum tractive effort expected from any locomotive with electric traction motors to the equivalent of about 16 per cent of its total weight on drivers. This limitation has been founded upon a realistic regard for such adversities as wet, icy, and even sometimes greasy rail, plus the almost universal aversion of railway operating officials to having trains stuck on mountain grades. A few instances of being forced to set out tonnage or to "double the hill" has convinced some otherwise adventuresome dispatchers to abide by this rather conservative adhesion limit. Electric locomotives commonly have their traction motors connected in series either permanently or during some of their operating sequences. While these arrangements obviously have many things to recommend them, one certainly is not the fact that they tend to accentuate any possible effects of slipping by one axle of a pair whose motors are in series. Slipping of one such axle brings the average torque of both motors to zero, thus causing the pair to unload. If a locomotive is working at or near its adhesive limit, this process of unloading may become cumulative with first one and then another pair of axles slipping until the entire locomotive relapses into a stall. Two remedies have been employed. The first is mechanical and involves the use of sensitive devices to detect and anticipate incipient slip by a single axle. Main reservoir air pressure is used to effect an instantaneous application of air brakes to the slipping axle. The objective is to keep full power applied to the axle which is at the slipping point and control slipping by

applying braking effort just sufficient to prevent any increase in rotational speed. This braking effort is then just as quickly removed as there is detectable evidence of a tendency for the axle to rotate more slowly. This process, sometimes called "no slip, no slide" control, has been fairly effective. The second remedy has already been mentioned. It is to employ conservative limits of working adhesion based upon year-around, all-weather operations and thus not permit the problem to arise. The whole affair is tending to solve itself to some extent through a changed attitude toward the operation of freight trains.

Nevertheless, most motive power authorities will agree with the general statement that diesel-hydraulic locomotives are more likely to "hold their feet" than electric-drive locomotives. The question is one of degree. Exactly how much more adhesion can these locomotives be counted upon to produce under the same adverse rail conditions that have dictated the 16 per cent upper limits for electricdrive units? The principal reason for the greater adhesive ability of the hydraulic drive seems to arise from truck design which mechanically couples all axles of one truck together. Thus slipping of one axle by itself is not possible. Most observers feel that this feature entitles the diesel-hydraulic units to higher adhesive ratings than electrics but probably not as much higher as some ardent advocates of the hydraulics would have us believe. The manufacturer of the units now under test is apparently rather conservative about claiming higher adhesive limits since published curves apparently limit the continuous tractive effort of these 165-ton locomotives to 76,000 pounds. This is 23 per cent adhesion. The quoted speed at this point is only 10.5 mph, however, which means that the continuous output of these units is 2128 rail horsepower quite a reduction from the so-called "4000 brake horsepower" of their nominal ratings. Some motive power observers would still like to see how this 23 per cent figure is realized in practice. Even should it prove entirely workable there are still some reasons to doubt that it proves very much about the future of motive power utilization.

Freight operating patterns changing

The competitive nature of modern railroading is perhaps nowhere demonstrated more forcefully than in the tendency to sack the age-old practice of operating mostly "drag freights" in favor of operating mostly "hotshots" on what used to be thought of as passenger-train schedules. These latter-day flagships of their fleets have replaced the time-honored varnish in the concern of all operating personnel from vice-presidents to brakemen. They are run up hill and down dale as fast as the track will permit. Motive power must necessarily reflect operating requirements. When the custom is to hang as much tonnage on a locomotive as it will possibly handle over a ruling grade, adhesion is something of considerable concern. If in the process of extracting maximum continuous tractive effort from a locomotive the speed falls to 10 mph - so what? When, however, changes in operational techniques call for running freight trains up even 2 per cent grades at 30 mph it is obvious that motive power requirements have been affected fundamentally. It now appears that the ability to develop high rail horsepower and maintain this horsepower over the entire speed range of the locomotive is a characteristic more to be sought after than high adhesions at low speeds. And it is this increasing emphasis upon high rail horsepower output at higher speeds that gives electrification advocates at least some cause for rejoicing. We feel that we have something in the roundhouse-or maybe it should be the "squarehouse" - that should be of inter

ever, and be fairly representative for purposes of comparison. The curves for the electric unit have also been synthesized in the sense that they represent a commercial frequency (60-cycle) rectifier type locomotive with six 625 rail horsepower traction motors built into a total cab weight of 165 tons. This is likewise the weight of the diesel-hydraulic locomotive and permits a direct comparison of two locomotives of equal total weight with all axles of both units powered.

Three curves are shown for the electric locomotive, which illustrates one of the points of superiority of locomotives with electric traction motors supplied from a central station. A locomotive forced to carry its own prime mover around as dead weight, such as a diesel, has no overload ability whatsover. This is true irrespective of its form of transmission. The limitation is in the prime mover itself. An electric locomotive supplied from a central station enjoys a number of advantages. Trolleyfed locomotives can supply all of their auxiliaries including motor ventilation equipment without diminishing the power available for traction. Electric traction motors can be given several ratings. There is the full load or continuous rating, and then there are incremental ratings above the continuous based upon motor heating limitations. These latter are known as "short-time" ratings, and their use must, of course, be closely monitored and conditioned by operating needs. Obviously the only continuous rating is the full-load rating, but the curves representing 1.1 and 1.5 times continuous are useful as representing possible operations for short periods for purposes of acceleration and for the negotiation of grades less than ruling at speeds higher than otherwise possible. The ability to utilize these short-time ratings for

est.