Electrification is the process of powering by electricity and is usually associated with changing over from another power source. The broad meaning of the term, such as in the history of technology and economic history, usually applies to a region or national economy. Broadly speaking, electrification was the build out of the electrical generating and distribution systems which occurred in the United States, Britain and other countries from the mid-1880s until around 1940 and is in progress in rural areas in some developing countries. This included the change over from line shaft and belt drive using steam engines and water power to electric motors.
The electrification of particular sectors of the economy is called by terms such as factory electrification, household electrification, rural electrification or railway electrification. It may also apply to changing industrial processes such as smelting, melting, separating or refining from coal or coke heating or chemical processes to some type of electric process such as electric arc furnace, electric induction or resistance heating or electrolysis or electrolytic separating.
History of electrification 
Development of magnetos, dynamos and generators 
In 1831 Michael Faraday, using a magnet and rotating copper disc, demonstrated that a moving conductor can be used to generate electricity. Around 1832, Hippolyte Pixii improved the magneto by using a wire wound horseshoe, with the extra coils of conductor generating more current, but it was AC. André-Marie Ampère suggested a means of converting current from Pixii's magneto to DC using a rocking switch. Later segmented commutators were used to produce direct current.
William Fothergill Cooke and Charles Wheatstone developed a telegraph around 1838-40. In 1840 Wheatstone was using a magneto that he developed to power the telegraph. Wheatstone and Cooke made an important improvement in electrical generation by using a battery powered electromagnet in place of a permanent magnet, which they patented in 1845.
The self-excited magnetic field dynamo did away with the battery to power electromagnets. This type dynamo was made by several people in 1866.
The first practical generator made by Z.T Gramme, who sold many of these machines in the 1870s.
E.E.B. Crompton improved the generator to allow better air cooling and made other mechanical improvements. Compound winding, which gave more stable voltage with load, improved operating characteristics of generators.
The improvements in electrical generation technology increased the efficiency and reliability greatly in the 19th century. The first magnetos only converted a few percent of mechanical energy to electricity. By the end of the 19th century the highest efficiencies were over 90%.
Electric lighting 
Arc lighting 
The use of electricity to produce an arc with carbon electrodes was discovered by Humphry Davy in 1802, but it was not used to any great extent until a practical means of generating electricity was developed.
Carbon arc lamps were started by making contact between two carbon electrodes, which were then separated to within a narrow gap. Because the carbon burned away, the gap must be constantly readjusted. Several mechanisms developed to regulate the arc. A common approach was to feed a carbon electrode by gravity and maintain the gap with a pair of electromagnets, one of which retracted the upper carbon after the arc was started and the second controlled a brake on the gravity feed.
In 1857 a joint British and French company began electrifying English lighthouses, using arc lamps powered by electricity generated using large magnetos. Arc lamps began being manufactured after the development of the Gramme generator in the early 1870s, and near the end of the decade were being used for lighting of street and parks. In the next few years they began being used in factories and large buildings.
Incandescent light bulbs 
Various forms of incandescent light bulbs had numerous inventors; however, the most successful early bulbs were those that used a carbon filament sealed in a high vacuum. These were patented by Thomas Edison in 1879 in the U.S. and Joseph Swan in 1880 in Britain. Edison’s lamp was more successful than Swan’s because Edison used a thinner filament, giving it higher resistance and thus conducting much less current. Edison began commercial production of carbon filament bulbs in 1880. Swan's light began commercial production in 1881.
Central power stations and isolated systems 
The first central station providing public power is believed to be one at Godalming, Surrey, U.K. autumn 1881. The system was proposed after the town failed to reach an agreement on the rate charged by the gas company, so the town council decided to use electricity. The system supplied arc lamps on the main streets and incandescent lamps on a few side streets. By 1882 between 8 and 10 households were connected, with a total of 57 lights. The system was not a commercial success and the town reverted to gas.
The first large scale central power station was Edison's Pearl Street Station in New York, which began operating in September, 1882. The station had six 200 horsepower Edison dynamos, each powered by a separate steam engine. It was located in a business and commercial district and supplied 110 volt direct current to 85 customers with 400 lamps. By 1884 Pearl Street was supplying 508 customers with 10,164 lamps.
By mid-1880s, in addition to Edison Co., other electric companies establishing central stations power and distributing power were the Thomson-Houston Electric Company and Westinghouse. By 1890 there were 1000 central stations in operation. The 1902 census listed 3,620 central stations. By 1925 half of power was provided by central stations.
Load factor 
The ratio of the average load to the peak load of a central station is called the load factor.
One of the biggest problems facing the early power companies was the hourly variable demand. When lighting was practically the only use of electricity, demand was high during the first hours before the workday and the evening hours when demand peaked. As a consequence, most early electric companies did not provide daytime service, with two-thirds providing no daytime service in 1897.
For electric companies to increase profitability and lower rates, it was necessary to increase the load factor. The way this was eventually accomplished was through motor load. Motors are used more during daytime and many run continuously. (See: Continuous production) Electric street railways were ideal for load balancing.Many electric railways generated their own power and also sold power and operated distribution systems.
New York Edison's load factor increased from 19.3% in 1884 to 29.4% in 1908. By 1929 the national central station load factor was greater than 50%, mainly due to motor load.
Isolated systems or self-generated power 
Before widespread power distribution from central stations, many factories, large hotels, apartment and office buildings had their own power generation. Often this was economically attractive because the exhaust steam could be used for building and industrial process heat, which today is known as cogeneration or combined heat and power (CHP). Most self-generated power became uneconomical as power prices fell. In the U.S. in 1902, isolated power systems greatly outnumbered central stations. By 1930 half of industrial power in the U.S. was purchased and half self generated.
Cogeneration is still commonly practiced in many industries that use large amounts of both steam and power, such as pulp and paper, chemicals and refining. The continued use of private electric generators is called microgeneration.
Electric motors 
Direct current electric motors 
Frank J. Sprague developed the first successful DC motor (ca. 1884) by solving the problem of maintaining a constant speed with varying load and reducing sparking from the brushes. Sprague sold his motor through Edison Co. Sprague also developed a system that allowed separate motors in a group to collect current from the overhead bus powering railway cars while allowing the motors to all be controlled from the engineer’s cab. In 1887 Sprague used his motors to power a street railway in Richmond, Virginia.
It is easy to vary speed with DC motors, which made them suited for a number of applications such as electric street railways, machine tools and certain other industrial applications where speed control was desirable.
Alternating current electric motors 
A problem in the development of the AC motor was getting it to start. Nikola Tesla was able to overcome the starting problem by using a rotating magnetic field. Tesla's concept was to use poly-phase current to produce the rotating field. Tesla developed the first practical AC motors in 1888. By 1895 GE and Westinghouse both had AC motors on the market. With single phase current either a capacitor or coil (creating inductance) can be used on part of the circuit inside the motor to create a rotating magnetic field. Capacitors are also commonly used to assist starting of single phase motors.
AC motors are typically either synchronous or induction motors. Synchronous motors lock into a multiple of the frequency, depending on the number of poles. Induction motors rotate at a slightly slower speed that is related to the frequency, again with the speed depending on the number of poles.
In 1897 Tesla patented an early type induction motor. Because induction motors are economical and run at constant speed, they are the most common type of motor in both industrial and household applications.
Multi-speed AC motors that have separately wired poles have long been available, the most common being two speed. Speed of these motors is changed by switching sets of poles on or off, which was done with a special motor starter for larger motors, or a simple multiple speed switch for fractional horsepower motors.
Since the development of silicon-controlled rectifiers and inverters it has been economical to regulate the speed of ordinary AC motors by adjusting the frequency. This type speed control has become common in industrial applications in recent decades.
Alternating versus direct current 
Factors favoring alternating current for energy transmission and distribution were:
- Alternating current can be transformed to high voltage to reduce transmission losses
- AC motors run at constant speeds, operate without brushes and are efficient
For direct current, power losses in an electrical conductor are proportional to the square of the current carried, while power transmitted is equal to the voltage times the current. Therefore, for a given amount of power transmitted, the higher the voltage, the lower the power losses by a factor proportional to the square of the reduced current. For example, for transmitting the same power, increasing the voltage by a factor of 10 reduces the current by a factor of 10 and the power loss by a factor of 100. However, to compare losses with DC to AC, it is necessary to correct for power factor, which would slightly increase the power loss. See: Electric power
In power generation, voltage is typically limited to just over 2000 volts, above which arcing will occur in the generator. Although electricity can be generated at 2000 volts, this voltage is too dangerous for most uses. Because there was no simple and economical way to transform voltage with direct current in early systems, DC was generated at the voltage that it was distributed to users, which usually was from 100 to 200 volts. This resulted in high transmission and distribution losses. With AC, the voltage can easily be changed with a transformer. The typical arrangement is to use a step up transformer to increase the voltage for distance transmission and a step down transformer near the point of local distribution.
Despite the superiority of alternating current for most applications, a few existing DC systems continued to operate for several decades after AC became the standard for new systems.
Poly-phase current 
Polyphase current generators and motors were developed in the mid to late 1880s in part by several engineers and inventors working on independent lines of inquiry including the Italian physicist Galileo Ferraris, American engineers Charles S. Bradley and Nikola Tesla, and the German technician Friedrich August Haselwander. It would be another decade after their work before complete practical Polyphase system were developed by manufacturers.
Polyphase current can be generated by having a separate commutator connected to different poles of an alternator. In commonly used three phase power, the poles are spaced 120 degrees apart and each will produce a sine wave pattern of current and voltage 120 degrees apart. Three phase power is used in commercial and industrial applications but not normally in households.
It is possible to generate poly phase current in a number of phases. The efficiency increases with the number of poles, but so does the number of wires. The marginal benefit of four phase compared to three phase was not considered worth the cost of an additional wire.
The direction of rotation of a three phase motor can be easily reversed by interchanging any two non-neutral wires.
Transmission and distribution of power 
Pioneering work on AC transmission was being conducted in Europe during the 1880s while the U. S. focused on DC, which was favored by Edison.
In 1887-9 a 10,000 volt AC generating station was built by Ferranti at Deptford on Themes to supply London. In an 1885 experiment a generator was installed at Ceril to supply AC to Paris, a distance of 56 km.
On a trip to Europe, George Westinghouse learned of AC research and development there. In 1885 Westinghouse and the electrical engineer William Stanley obtained certain patent rights and developed AC lighting using an improved transformer developed by Stanley. In 1886 Westinghouse installed a transmission system using a 20:1 step up voltage with step-down. In 1890 Westinghouse and Stanley developed a system to transmitting power several miles for a mine in Colorado. In 1893 Westinghouse was awarded the contract to supply AC power for the World's Colombian Exposition at a fraction of the competing bid by Edison Co. for a DC system.
One of the most decisive events for alternating current was the decision to use AC for power transmission from the Niagara Power Project to Buffalo, New York. Proposals submitted by vendors in 1890 included DC and compressed air systems. A combination DC and compressed air system remained under consideration until late in the schedule. Niagara commissioner William Thompson (Lord Kelvin) argued that using AC power would be a serious mistake. Ongoing developments and new experience with AC eventually shifted the decision AC, which had been proposed by both Westinghouse and General Electric. In October 1893 Westinghouse was awarded the contract to provide the first three 5,000 hp, 250 rpm, 25 Hz, two phase generators.
Electrical grid 
With the realization of long distance power transmission it was possible to interconnect different central stations to balance loads and improve load factors. Interconnection became increasingly desirable as electrification grew rapidly in the early years of the 20th century, but it became a national objective in the United States after the power crisis during the summer of 1918 in the midst of World War I. Interconnection progressed in the U.S. and Europe over the following decades.
Interconnection helped the spread of electrification to rural areas in the United States. Rural areas in Europe were electrified earlier than in the U.S.
Household electrification 
The electrification of households in the U.S. began around 1905 in major cities and in areas served by electric railways and increased rapidly until about 1930 when 70% of households were electrified. Many of the remaining mostly rural households were electrified before 1950 by the Rural Electrification Administration.
Rural electrification 
In the U. S. in 1930, only 10% of farms had electricity. Partly through the establishment of the Rural Electric Administration (REA) in 1935, the percentage of farms with electricity increased to 33% in 1940. Farms were electrified in Europe before the U.S.
Steam turbines 
The efficiency of steam prime movers in converting the heat energy of fuel into mechanical work was a critical factor in the economic operation of steam central generating stations. Early projects used reciprocating steam engines, operating at relatively low speeds. The introduction of the steam turbine fundamentally changed the economics of central station operations. Steam turbines could be made in larger ratings than reciprocating engines, and generally had higher efficiency. The speed of steam turbines did not fluctuate cyclically during each revolution; making parallel operation of AC generators feasible, and improved the stability of rotary converters for production of direct current for traction and industrial uses. Steam turbines ran at higher speed than reciprocating engines, not being limited by the allowable speed of a piston in a cylinder. This made them more compatible with AC generators with only two or four poles; no gearbox or belted speed increaser was needed between the engine and the generator. It was costly and ultimately impossible to provide a belt-drive between a low-speed engine and a high-speed generator in the very large ratings required for central station service.
Parsons turbines were widely introduced in English central stations by 1895. The first U.S. turbines were two De Leval units at Edison Co. in New York in 1895. The first U.S. Parsons turbine was at Westinghouse Air Brake Co. near Pittsburgh.
Steam turbines had capital cost and operating advantages over reciprocating engines. The condensate from steam engines was contaminated with oil and could not be reused, while condensate from a turbine is clean and typically reused. Steam turbines were a fraction of the size and weight of comparably rated reciprocating steam engine. Steam turbines can operate for years with almost no wear. Reciprocating steam engines required high maintenance. Steam turbines can be manufactured with capacities far larger than any steam engines ever made, giving important economies of scale.
Steam turbines could be built to operate on higher pressure and temperature steam. A fundamental principle of thermodynamics is that the higher the temperature of the steam entering an engine, the higher the efficiency. The introduction of steam turbines motivated a series of improvements in temperatures and pressures. The resulting increased conversion efficiency lowered electricity prices.
The power density of boilers was increased by using forced combustion air and by using compressed air to feed pulverized coal. Also, coal handling was mechanized and automated.
Electric street railways (trams or trolleys) 
One of the first uses of electricity was electric street railways, which became a major transportation infrastructure before being displaced by motor buses and automobiles.
Electrochemistry provided a means to isolate numerous elements that were previously difficult separate by other means. Using electrochemical processes greatly lowered the cost of these chemicals and created major industries. Some common electrochemicals are:
- Sodium (commonly as sodium hydroxide)
- Potassium (commonly as potassium hydroxide)
- Refined copper (electrolytic)
Electric furnaces 
Electric furnaces can produce high temperature heat needed to melt or smelt metals with melting points higher than attainable with conventional fossil fuel furnaces. Electric furnaces also avoid problems of contamination caused by sulfur and other compounds present in fossil fuels.
Historical cost of electricity 
Central station electric power generating provided power more efficiently and at lower cost than small generators. The capital and operating cost per unit of power were also cheaper with central stations. The cost of electricity fell dramatically in the first decades of the twentieth century due to the introduction of steam turbines and the improved load factor after the introduction of AC motors. As electricity prices fell, usage increased dramatically and central stations were scaled up to enormous sizes, creating significant economies of scale. For the historical cost see Ayres-Warr (2002) Fig. 3
Benefits of electrification 
Benefits of electric lighting 
Electric lighting was highly desirable. The light was much brighter than oil or gas lamps, and there was no soot. Although early electricity was very expensive compared to today, it was far cheaper and more convenient than oil or gas lighting. Electric lighting was so much safer than oil or gas that some companies were able to pay for the electricity with the insurance savings.
Pre-electric power 
"One of the inventions most important to a class of highly skilled workers (engineers) would be a small motive power - ranging perhaps from the force of from half a man to that of two horses, which might commence as well as cease its action at a moment's notice, require no expense of time for its management and be of modest cost both in original cost and in daily expense." Charles Babbage, 1851
To be efficient steam engines needed to be several hundred horsepower. Steam engines and boilers also required operators and maintenance. For these reasons the smallest commercial steam engines were about 2 horsepower. This was above the need for many small shops. Also, a small steam engine and boiler cost about $7,000 while an old blind horse that could develop 1/2 horsepower cost $20 or less. Machinery to use horses for power cost $300 or less.
Many power requirements were less than that of a horse. Shop machines, such as woodworking lathes, were often powered with a one or two man crank. Household sewing machines were powered with a foot treadle; however, factory sewing machines were steam powered from a line shaft. Dogs were sometimes used on machines such as a treadmill, which could be adapted to churn butter.
Electric motors were several times more efficient than small steam engines because central station generation were more efficient than small steam engines and because line shafts and belts had high friction losses.
Electric motors were more efficient than human or animal power. The conversion efficiency for animal feed to work is between 4 and 5% compared to over 30% for electricity generated using coal.
Economic impact of electrification 
From 1870-80 each man-hour was provided with .55 hp. In 1950 each man-hour was provided with 5 hp, or a 3% annual increase, declining to 1.5% from 1930-50.
The period of electrification of factories and households in the U. S., from 1900 to 1940, was one of high productivity and economic growth.
In economics, the efficiency of electrical generation has been shown to correlate with technological progress.
Power sources for generation of electricity 
Most electricity is generated by thermal power stations or steam plants, the majority of which are fossil fuel power stations that burn coal, natural gas, fuel oil or bio-fuels, such as wood waste and black liquor from chemical pulping.
The most efficient thermal system is combined cycle in which a combustion turbine powers a generator using the high temperature combustion gases and then exhausts the cooler combustion gases to generate low pressure steam for conventional steam cycle generation.
Hydroelectricity uses a water turbine to generate power. Between 1880 and 1895, hydropower was beginning to be used for generating electricity; these first hydroelectric plants produced direct current (DC) used mostly to power nearby arc and incandescent lighting.
Advances in recent decades greatly lowered the cost of wind power making it one of the most competitive alternate energies and competitive with higher priced natural gas (before shale gas). Wind energy's main problem is that it is too intermittent and there is no practical storage infrastructure.
Geothermal requires very hot underground temperatures near the surface to generate steam which is used in a low temperature steam plant. Geothermal power is only used in a few areas. Italy supplies all of the electrified rail network with geothermal power.
Electrification pioneers 
Energy resilience 
- the ‘stickiest’ form of energy: it stays in the continent where it is produced.
- multi-sourced. If one source suffers a shortage, electricity can be produced from another, including renewable sources.
As a result, it gives the greatest degree of energy resilience and the energy system is going to electrification.
See also 
|Look up electrification in Wiktionary, the free dictionary.|
- Electric vehicle
- GOELRO plan
- Mains electricity by country Plugs, voltages and frequencies
- Railway electrification system
- Renewable electricity
- Renewable energy development
- Rural electrification
- Devine, Jr., Warren D. (1983). From Shafts to Wires: Historical Perspective on Electrification, Journal of Economic History, Vol. 43, Issue 2. p. 355
- *Nye, David E. (1990). Electrifying America: Social Meanings of a New Technology. The MIT Press. Text "Cambridge, MA, USA and London, England " ignored (help)
- Constable, George; Somerville, Bob (2003). A Century of Innovation: Twenty Engineering Achievements That Transformed Our Lives. Washington, DC: Joseph Henry Press. ISBN 0-309-08908-5.
- McNeil 1990
- McNeil 1990, pp. 359
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- McNeil 1990, pp. 360–65
- McNeil 1990, pp. 366–68
- McNeil 1990, pp. 369
- Hunter & Bryant 1991, p. 191.
- Hunter & Bryant 1991, p. 242
- Hunter & Bryant 1991, pp. 276–9
- Hunter & Bryant 1991, pp. 212 Note 53
- Hunter & Bryant 1991, pp. 283–4
- Nye 1990, pp. 195
- Hunter & Bryant 1991, pp. 248
- McNeil 1990, pp. 383
- Hunter & Bryant 1991, pp. 250
- Hunter & Bryant 1991, pp. 221
- Hunter & Bryant 1991, pp. 253, Note 18
- Thomas Parker Hughes, Networks of Power: Electrification in Western Society, 1880-1930, JHU Press - 1993, page 118
- [[David Landes|Landes, David. S.]] (1969). The Unbound Prometheus: Technological Change and Industrial Development in Western Europe from 1750 to the Present. Cambridge, New York: Press Syndicate of the University of Cambridge. p. 286. ISBN 0-521-09418-6
- Hunter & Bryant 1991, pp. 285–6
- Moore, Stephen; Simon, Julian (Dec. 15, 1999). The Greatest Century That Ever Was: 25 Miraculous Trends of the last 100 Years, The Cato Institute: Policy Analysis, No. 364. p. 20 Fig. 16Fig 13.
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- Steam-its generation and use. Babcock & Wilcox. (Numerous editions).
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- [Vaclav] (2006). Transforming the Twentieth Century: Technical Innovations and Their Consequences. Oxford, New York: Oxford University Press. p. 33<Mximum turbine size grew to about 200 MW in 1920s and again to about 1000 MW in 1960. Significant increases in efficiency accompanied each increase in scale.>
- Ayres, R. U.; Ayres, L. W.; Warr, B. (2002). Exergy, Power and Work in the U. S. Economy 1900-1998, Insead’s Center For the Management of Environmental Resources, 2002/52/EPS/CMER
- Cardwell, D. S. L. (1972). Technology Science and History. London: Heinemann. p. 163.
- Unskilled labor made approximately $1.25 per 10 to 12 hour day. Hunter & Bryant cite a letter from Benjamin Latrobe to John Stevens ca. 1814 giving the cost of two old blind horses used to power a mill at $20 and $14. A good dray horse cost $165.
- Hunter & Bryant 1991, pp. 29–30
- Hunter & Bryant 1991
- Two Paradigms of Production and Growth
- Kendrick, John W. (1980). Productivity in the United States: Trends and Cycles. The Johns Hopkins University Press. p. 97. ISBN 978-0-8018-2289-6
- Energy Timelines - Hydropower
- "Our Electric Future — The American, A Magazine of Ideas". American.com. 2009-06-15. Retrieved 2009-06-19.
Hunter, Louis C.; Bryant, Lynwood; Bryant, Lynwood (1991). A History of Industrial Power in the United States, 1730-1930, Vol. 3: The Transmission of Power. Cambridge, Massachusetts, London: MIT Press. ISBN 0-262-08198-9.
- Hills, Richard Leslie (1993). Power from Steam: A History of the Stationary Steam Engine (paperback ed.). Cambridge University Press,. p. 244. ISBN ISBN 0-521-45834-X, 9780521458344 Check
|isbn=value (help). Retrieved May 2012.
- McNeil, Ian (1990). An Encyclopedia of the History of Technology. London: Routledge. ISBN 0-415-14792-1.
- Nye, David E. (1990). Electrifying America: Social Meanings of a New Technology. The MIT Press. Text "Cambridge, MA, USA and London, England " ignored (help)
- Zambesi Rapids - Rural electrification with water power