OCO-4& PAE Y2 Public Welfare Service Bulletin No. 2 (Seventh Edition) 1927 LOF TH OCT 1 9 19 a UNIVe ig a ASITY og Aunojg ELECTRICITY How It Is Made and How Distributed For Use of School Students, English and Current Topics Classes, and Debating Clubs Issued by ILLINOIS COMMITTEE on PUBLIC UTILITY INFORMATION 79 West Monroe Street - . - - Chicago, Illinois (Additional copies will be furnished on request) ELECTRICITY —The Burden Bearer Introductory: Electricity, nature’s gigantic energy and today the burden bearer of the world, has revolutionized life, commerce and industry within the memory oi men now alive. Within the past half century it has made possible greater progress than was made in all the preceding years. Man has learned to harness, distribute and util- ize this magic power for day and night service throughout the civilized world. It is banishing darkness, has lightened the burden of the house- wife and has become the silent partner of indus- try. The story of the development of the use of electricity is a fascinating recital. It is a story of progress. Electricity has brought about a rev- olution in industry, for it has enabled one man to do the work of many men, and has made pos- sible huge production in our factories, rapid trans- portation and better living conditions in our homes. It has built our great cities and industrial centers. It has torn away the barriers of time and distance and made all men _ neighbors. Through radio it has brought entertainment and knowledge to millions. Your ‘‘Thirty Slaves:” The Smithsonian Institution has figured that if all our machinery operated by electrical and steam power should be taken away, it would require the services of 30 times as many hardworking slaves as we have population to duplicate the work done in America. In other words, the use of power and machinery gives to every man, woman and child in our country the equivalent of 30 slaves, hence the average family of five has 150 “slaves” working for it. But instead of this army of slaves we have elec- tricity working for us at a “wage” so small that it brings its services within reach of the poorest man’s pocketbook; a sum so small that it would not pay for a servant’s meals. Push a button and the home is illuminated as by the midday sun; an electric vacuum cleaner banishes dirt and dust; an electric washing ma- chine and electric iron help with the housework; . a fan gives cooling breezes and an electric heater radiates warmth; an electric range cooks the fam- ily meal; an electric refrigerator makes ice, and many other familiar labor-saving appliances are placed in action. Today, electricity rings the door bell; tows a ship through the Panama Canal; lifts a great bridge; milks the cows; chops feed on the farm; increases production in factories by providing good lighting and ample power; lights homes and stores ; even provides illumination for surgical op- erations in hospitals. It is ready to perform these tasks 24 hours of each day. Yet it was only a short time ago—less than 50 a years—that the richest kings had none of the com- monplace conveniences which make life easier and better for even the poorest Americans at the pres- ent time. This change is due to the tremendous efforts of the nation’s electric utilities. The Great Minds of Electricity: Many great minds have contributed to the de- velopment of the present-day electric central-sta- tion systems which provide our electricity. If only one name were to be mentioned, it undoubt- edly would be that of Thomas A. Edison. But before Edison, with his marvelous inventions, and contemporary with him, were a host of other electrical scientists and inventors who contrib- uted their part. Such men as Dr. William Gilbert, Benjamin Franklin, Luigi Galvani, Alesandro Volta, Sir Humphrey Davy, H. C. Oersted, A. M. Ampere, G. S. Ohm, Charles Wheatstone, Michael Fara- day, Joseph Henry, Z. T. Gramme, J. C. Max- well, A. Pacinotti, S. Z. deFerranti, Werner von Siemens, Lord Kelvin and many others did very important work. Since Edison’s discoveries other scientists, among them the late Dr. Charles P. Steinmetz, have added achievements of great value. Early Inventions: Although the electric light and power business, as we know it today, is a development of com- paratively recent origin, the foundations for it were laid by early experimenters in the Seven- teenth and Eighteenth centuries. Back in 1600, Dr. Gilbert, an English physician, conducted nu- merous experiments and made many important discoveries, but it was nearly a century and a half later before any great progress was made by others who studied the subject. Benjamin Franklin’s demonstration by his fa- mous kite experiment in 1752, proving that light- ning is an electrical phenomenon, is well known. About 1790 Galvani discovered a current of elec- tricity. Up to that time electricity had been de- veloped only by friction. Volta developed the electric battery in 1800. Oersted of Copenhagen in 1820 discovered the magnetic effect of electric current. This paved the way for the later devel- opment of electrical machinery. Michael Fara- day of England in 1831 discovered the basic prin- ciples on which dynamo electric machines are de- signed. Many other scientists and inventors made important discoveries during the early part of the Nineteenth century. The telegraph was the first great electrical in- vention. It was invented by Morse in 1837. Elec- troplating was perfected about the same time. The electric motor was developed about 1873. Radio is a development of the present generation. The First Central Station: Development of the electrical industry, how- ever, really dates from September 4, 1882, when the first central electricity generating station in the world was opened in New York city and fur- nished electricity for lighting a small area in downtown Manhattan. Three .years before this Edison had invented the electric light but the light had been regarded as an impractical curiosity until the central sta- tion, known as the Pearl Street station, was opened. With this opening a new epoch in elec- tricity began for the basic principles of this plant were the same as those used today by electric power and light companies. This station—opened little more than four dec- ades ago—served 59 customers, and from this be- ginning the electric industry has grown until now there are 20,500,000 customers, of whom 16,650,- 000 take residential lighting service. Customers of electric light and power companies doubled between 1909 and 1915 and again: doubled in the six years following. The annual increase now is about 2,000,000 customers. The Pearl Street station had six generators with a total generating capacity of 559.5 kilo- watts. The capacity in the United States in 1927 was 23,000,000 kilowatts or almost 31,000,000 horsepower. Output of electricity in 1926 set a new record with more than 73,000,000 kilowatt-hours. The Commonwealth Edison Company, serving Chi- cago, produced a 1926 output of 3,482,632,000 kilo- watt-hours of energy, a 12.7 per cent increase over the previous year, and the largest single production of any steam central station in the world. Development of the electric industry may be seen from the fact the Commonwealth Edison Company had a generating capacity of only 640 kilowatts in 1888. Today the electric industry represents an in- vestment of $8,400,000,000 and about $900,000,- 000 is invested annually in new plants, equipment and extensions made necessary by constant de- mands for increased service. Gross revenue of the electric light and power companies of the country in 1926 was $1,630,000,- 000. The industry is owned by more than 2,500,- 000 men and women investors, banks, insurance companies and others whose money has pro- vided funds for building up the great electric systems whose services are available to all. Where Electricity Comes From: Electric light and power service starts at the central generating plant—called the “central sta- tion’”—where electric energy is produced in large quantities. From these central stations wires carry the energy to the homes, stores and fac- tories of the nation—to provide illumination, to turn the wheels of the machines in factories, to operate electric railway cars and to help the housekeeper by supplying energy for her vacuum cleaner, toaster, flat iron, washing machine and other appliances. Electricity is produced most economically in central stations where large generators are used, and it is transmitted and distributed at much less expense if all of the electrical needs of one large community, or several small communities, are supplied from one common system of wires. Therefore, the modern tendency is to replace small generating stations with substations, which are distributing stations for the large systems. This gives the benefit of the economies of the large stations to small communities. There are two kinds of electricity made and distributed by a central station—‘“direct” and “alternating.” Direct, or continuous current, flows constantly in one direction. This kind of current, because it cannot be sent any great dis- tance, is used largely in the congested centers of populous cities. Alternating current flows first in one direction, then reverses, but so fast that the changes cannot be detected in an electric light by the naked eye, except in low cycles, in which it is visible. This has resulted in adoption of a gen- eral standard of 60 cycles for lighting. Alternat- ing current can be sent, economically, hundreds oi miles, and, therefore, now is used almost uni- versally. Statistical Data Showing Development of Electric Light and Power Industry in the United States During the Last 25 Years Capital Invested. $504,740,352)$2,175,678,266 | $5,100,000,000/ $5,800,000,000/$6,600,000,000) $7,500,000,000) $8,400,000,000 Gross Revenue...... 78,735,500} 302,273,398] 1,084,000,000} 1,300,000,000] 1,350,100,000/ 1,475,000,000} 1,630,000,000 Kilowatt Capacity 1,212,200 5,165,439 14,313,438 17,000,000 18,840,000 20,000,000 23,000,000 Total Customers Aa Ny 7 eae 1,465,060 3,837,518 12,353,790 14,400,000 16,500,000 18,500,000 20,500,000 Residence Cus- tomers ............. ey 9,903,830 11,620,000 13,350,000 15,000,000 16,650,000 Commercial Cus- eoniers)... 1,988,020 2,260,000 2,560,000 2,850,000 3,140,000 Power Customers 461,940 520,000 590,000 650,000 710,000 Total Generation in Kilowatt- NOucS ..... 2,507,051,515! 11,569,109,885!44,084,575,000! 51,498,450,000! 59,013,590,000! 65,870,000,000!73,000,000,000 How Electricity Is Made Available: Electricity is produced from some form of heat energy, as that obtained by the combustion of coal, oil, gas or wood; from some form of me- chanical energy like that of falling water or (to a slight extent) wind power, or from chemical energy, as in batteries. In the case of water- power plants the momentum of the falling water is used to revolve waterwheels which in turn op- erate electric generators. The water may be small in volume but have a great pressure because of a high fall, or it may have low pressure and much volume, or have any combination of these quali- ties. The most desirable class of streams for water power developments are those having a fairly con- stant flow throughout the year. This covers a comparatively small number of streams. Utilization of these streams is expensive as water-storage facilities are necessary to keep water available throughout the year. Then there are “flashy” streams—erratic and experiencing sudden and short flood periods with intervening periods of little or no water. They are uneconomical for development. ‘This class includes many Middle Western streams. Water power development also may be uneco- nomical if the proposed site is so far from the power market as to make necessary an extremely expensive transmission line, or because of large power losses through transmission over a great distance. Because most of the streams in Illinois are in the “flashy” class very little water power has been developed in this state, less than 4 per cent of the electricity being produced in this man- ner. Sometimes electric generating plants are built right at the coal mine in Illinois and other states. This is seldom practical, however, as efficient op- eration of turbines requires from 500 to 700 tons of water for every ton of coal burned, to chill the condenser tubes and to condense steam after it has done its work in the turbines. In New York, Chicago, Philadelphia, Boston, and other large cities, more water is pumped for condensing purposes in electric generating sta- tions than the city water-works pump for all oth- er purposes. This need of an abundance of water is an outstanding reason why more generating plants cannot be built at the mouths of coal mines, where there is seldom a large supply of water. At the central station the coal is handled by mechanical conveyors and crushers, themselves operated by electricity, and is delivered to the automatic stokers of the furnaces without being touched by human hands. The other raw material required is water. This is delivered to the boilers, where the heat of the burning coal con- verts it into steam. The steam is piped to the turbines, where the impact of its expansive force and its momentum rotate the shafts of the elec- tric generators. The Turbine: The principle of the steam turbine is very sim- ple. It is practically the same as the water tur- bine, and the water turbine is only an elaborated water wheel. The latter receives its power from water pressure of rivers or reservoirs of water so stored that when the water flows it strikes the blades of the wheel, rotating it and producing power with its pressure. In like manner steam generated in central station boilers by coal is directed against the blades of a steam turbine which rotates from this impact, perhaps 1,800 times a minute, and produces power. These tur- bines—“electric machines” or generators, as we now call them—are attached directly to the shaft without the use of belts. The energy we have so far pictured as being created in a central generating station is mechan- ical and not electrical energy, but right here, in the generator, the transformation takes place. The power that goes into the turbine as mechanical energy is taken from the generator at the other end of the shaft as electrical energy. In spite of the enormous power produced by a modern generator, the principle of its work is based on simple laws. Early experiments by the famous Faraday (born in England, 1791) marked the beginning of the electric generator, and the same laws that Faraday worked out are applied in the making of the huge generators of today. Nothing of importance has been added except elaboration of machinery. Faraday used a coil of wire and a magnet. Each time the magnet was thrust into the coil its magnetism was found to cause a flow of electricity in the coil, as indi- cated by a compass placed near the coil of wire. The same phenomenon takes place when a gen- erator rotates. It contains magnets and coils of wires, which are, of course, much stronger than those used by Faraday. As long as the magnet rotates inside the coil, electricity is generated. Nowadays the turbine and the generator are so closely related they are made in one complete unit known as a “turbo-generator.” The electricity which comes from the genera- tors is so powerful that it must be controlled very carefully. This is accomplished by means of copper switching devices. Copper is used be- cause it is one of the best conductors of electricity and is relatively cheap. Alternating current is often raised to high voltages, because at high pressure it can be economically transmitted long distances by comparatively small copper wires, and its voltage can be changed by transformers. Direct current is not adaptable for this long-dis- tance, high-voltage transmission, and its voltage cannot be changed by transformers. The Transformer: Although high voltages are necessary for trans- mission lines, electricity is generated and is used for lighting and power purposes at low voltages. Transformers are used, therefore, to “step” the voltage up as the current comes from the genera- tor and to “step” it down when it leaves the transmission line. Sometimes huge transformers are used in substations from which energy is distributed to large sections of a city or to small towns. The transformers, which are a familiar sight on poles in streets or alleys, finally reduce the pressure to a safe point for domestic use and send it into the dozen or more houses near which the transformer is located. The Basic Laws of Electrical Energy: Something very interesting takes place within the transformer. We have already noted above, in connection with the generator, that when a piece of magnetized iron was moved through a coil of wire electricity was produced. Early experiment- ers found that when electricity flowed through a coil of wire around a piece of iron magnetism was produced in the iron. These two principles taken together illustrate how a transformer works. Electrical energy travels from the power station into the transformer box and into a coil of wire which surrounds a piece of iron. The electricity in the coil magnetizes the iron and the magnet- ized iron in its turn produces electricity in an- other coil, which is around the magnet but entire- ly separate from the first coil. The pressure in the coils is proportionate to the turns of wire. The more wires in either of these two coils the more pressure we have; therefore, if one coil has ten times as many wires as the other, or “secondary” coil, the pressure at the other, or “secondary,” side of the transformer will be reduced to one- tenth of what it was when it entered it. From the other side of the transformer elec- tricity is led at low pressure into the house or factory through a service switch where it can be turned on or off, and then through a meter, which measures the current. After that it is available for household uses. In the case of the large neighborhood substations power taken from the secondary side of the large transformers is often used to operate street railways or street lighting circuits. Electricity Has Revolutionized Industry: Electricity has made America machineland. There are no less than 3,000 uses for electricity. Most oi them are in industry, and the use of elec- tricity for power, as well as for lighting and heat- ing in the home, is growing steadily. Although the use of electrical energy for driv- ing motors is its most common employment in industry, aside from illumination, it is being used more and more for generating heat and bringing about chemical reactions in many manufacturing processes. In the latter field electricity has a wide use in electro-chemistry, a department of industrial en- deavor with which most people are not familiar. In electro-chemistry, electricity is used to break down, build up, cover, uncover, separate and blend. Some remarkable accomplishments result. These are probably better understood by refer- ence to the experiment conducted in school lab- oratories of reducing water to its component parts, hydrogen and oxygen, by passing an elec- tric current through it. That is an example of breaking down. Electro-plating is an example of the building up process. In electro-plating, cop- per plates are immersed in a solution of silver nitrate and by passing current through the solu- tion, silver is deposited on one of the plates. There are many other reactions brought about by electricity on a large scale which are the bases of the electro-chemistry industry. Eighty per cent of the copper produced in the United States is separated from ore by electricity. Gold and silver are separated from the ore in the same way. Aluminium, nickel and silver are “recov- ered” from ore and waste. Almost all gold plated jewelry is gilded by electrolysis. Use of electricity for smelting ore is a compar- atively recent development. Making of “electric steel” is a fast-growing industry. By using electricity, vanadium and chrome— new kinds of steel—were produced. These are used for automobile and airplane parts and for castings where a “perfect texture is necessary. Electric steel is also utilized in making tools such as drilling bits which must stand hard usage. Electricity as a Producer of Heat: Electric heat is being applied to iron, nickel, copper, silver, brass and bronze and other non- ferrous metals. Electric furnaces produce such electro-chemical “mysteries” as ferro manganese silicon, tungsten, molybdenum, chromium and ti- tanium, abrasive materials such as carborundum, alaxite and magnesite. During recent years electricity has heen used extensively for operating electric ranges in those communities which do not have gas available. Through perfection of this appliance the house- wife in the smaller.community is able to cook as efficiently, cleanly and with the same degree of comfort as is possible in the larger cities. Electricity is being used extensively in coal mining. In Illinois, alone, hundreds of mines pur- chase all or part of their power from central sta- tions. Formerly, when coal mine operators gen- erated: their own electricity, 20 pounds of coal were burned to produce one kilowatt-hour. As modern central stations produce this same en- ergy with less than 2 pounds of coal, a great con- servation of fuel has taken place and the cost of power used in mining coal has been lowered. Future Development of Railroad Electrification: : One of the great developments of the future will be the more general electrification of steam railroads, as the experimental stage of this use ol electricity seems to be passed. In several cities in the United States the railroad terminals have been electrified, and through Montana, Idaho and Washington one large steam railroad has electri- fied its tracks for 600 miles over mountains. Four- thousand-ton trains go up and down steep moun- tain grades under perfect control at speeds never attained under steam operation, and with a regu- larity that leaves no doubt as to the practicabil- ity of electrification. All railroads leading into New York City are electrified within the city limits. In Illinois, the Illinois Central Railroad has electrified its tracks for suburban service, and is working on a general electrification program for its entire terminal facilities. When first placed in operation the electrification comprised from two to six parallel tracks extending thirty-five miles from the Randolph street terminal, and, with two electrified branch lines, made a total of 125 track miles. When completed, there will be as many as fifteen parallel tracks electrified, and in all there will be about 400 miles of track equipped, for elec- tric trains. Power Obtained from Central Stations: When the Illinois Central Railroad’s manage- ment planned for electrification of its Chicago terminal, it had expert engineers investigate a supply of power for the project. They reported that power could not only be purchased cheaper from electric light and power companies than it could be generated by the railroad, but that a pur- chased supply was much more reliable. Seven substations, provided by the central station com- panies serving Chicago and vicinity, supply the railroad with power for the operation of its trains, for its signals, and for its repair shops. Has Many Advantages Over Steam: Some of the public advantages of electrified steam railroad suburban service are greater com- fort, speed and frequency of service; extension of suburban residence districts, thus making avail- able a greater number of attractive home-sites ; in- crease in value of real estate; beautifying of resi- dential and shopping districts; advertising value to the city as a whole; elimination of the smoke nuisance; lessening of noise nuisance; making possible sub-surface operation of trains, which opens a way for through streets and lessens traf- fic congestion; and aiding the growth of small suburban towns by making them more a part of the big city. Engineers say that if all steam railroads were electrified and energy furnished by coal-burning generating stations, 136,000,000 tons of coal would be saved each year. If hydro-electric generating stations furnished one-third of the electricity, 162,000,000 tons of coal would be conserved each year. Farm Electrification: Electric light and power companies are devot- ing much time and effort to the electrification of farms in the belief that electricity will increase the productivity and the earnings of farm work- ers and make their life more pleasant, as it has done for residents of towns and cities. The use of electrically-operated labor-saving machinery has made the American worker the best paid worker in the world. The American farmers use more machinery and produce more per capita than do farmers in any other country. The tendency is towards the use of mechanical and electric power in place of man-power and animal-power. The value of electricity on the farm is deter- mined by both its economic advantage and its betterment of living conditions. From an eco- nomic standpoint, its value is measured by the labor displaced, increased production, and reduced cost of operating the farm. Its other value is that it makes farm life more pleasant, keeps the boys and girls from leaving for towns and cities, and gives to the farmer a pride and satisfaction that cannot be measured. Also, it opens up profitable lines of farming, which many farmers avoided because of the large amount of labor involved. Dairy farming is one of these farm activities which is made easier by electricity. Milking can be done electrically, the separator can be operated by an electric motor, and the milk and cream kept fresh and sweet in an electric refrigerator. Farm Electrification Experiments in Illinois: On ten farms near Tolono, Illinois, where there is a large diversity of operations and products, the University of Illinois is conducting experi- ments in rural electrification. Electric light and power companies of the state, farmers’ organiza- tions, and manufacturers of farm machinery and electric appliances are co-operating with the school. Accurate records of the cost of electricity used and the value of the products are kept. Elec- tricity is being used in dairying, poultry raising, PLANT V OUTDOOR HIGH VOLTAGE He |] ELECTRIC SWITCHING STATION ae | TRANSMISSI 4 My * xX —S OUTDOOR HIGH VOLTAGE STEP-DOWN TRANSFORMER ‘Nea stock farming, grain farming, seed production and general farming. It is believed that these experiments will bring about a more general use oi electricity on Illinois farms. Among the uses which have been found for elec- tricity on farms are: grain elevating, ensilage cutting, feed grinding, grain cleaning, grain threshing, hoisting hay, milking, mixing concrete, pumping water, refrigeration, sawing, cream sepa- rating, auxiliary heating, brooding chicks, incu- bating chicks, cooking, ironing, water heating, barn ventilation, corn shredding, corn shelling, timber utilization, dish washing, and lighting of houses, barns, poultry houses and out-buildings. Already many farms have electricity delivered to them by the central station plants and it is to be expected that within a short time the rural districts will have the same efficient and modern service possible in the thickly populated cities. As farmers develop more uses for electricity, the extension of service will increase. What an Electrical Map of the U. S. A. Would Look Like: If one could see, upon a map of the United States, outlines of systems for generating, trans- mitting and distributing electricity the impres- sion would be something like that of seeing a number of inter-connected spider-webs, each large generating station being the center of its own web. Each system may have several generating stations, the whole network being tied together in such a way that the breakdown of a machine in one generating station or the failure of a sub- station would not, usually, mean loss of service to the customer, other sources of supply being available in emergency. The same plants that serve the cities now fur- nish service to the smaller communities and to the farms. They are no longer local distributors, but reach out as far as their wires are strung. One company may serve hundreds of communi- ties from its central station energy-producing plants. That is why the rendering of service is now regulated by the state. It has outgrown its original city boundaries. PRIMARY LINE Be I SiS SS } me sauce