Manhattan Electrification: Difference between revisions

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=== References for Further Reading ===
=== References for Further Reading ===


Cunningham, Joseph J. ''Manhattan Power'' (North Charleston, SC: 2013).
Cunningham, Joseph J. ''New York Power'' (North Charleston, SC: 2013).


Cunningham, J. J. ‘‘Architect of Power: Thomas E. Murray and New York’s Electrical System,’’ ''IEEE Power & Energy Magazine'' 10, no. 2 (March–April 2012), pp. 80–94.
Cunningham, J. J. ‘‘Architect of Power: Thomas E. Murray and New York’s Electrical System,’’ ''IEEE Power & Energy Magazine'' 10, no. 2 (March–April 2012), pp. 80–94.

Latest revision as of 17:27, 7 June 2015

This article was initially written as part of the IEEE STARS program.

Citation

The first quarter century of electric utility operation in New York City represented a technological road map of the engineering and development of practical systems from the primitive arc street lamps of 1881 to the established commercial and industrial supplies of 1906.

Essay

Introduction

The first 20 years of electric power development in Manhattan represents the birth of commercial utility systems in what is still the world’s most densely concentrated site of electrical load. Commercial sales began with the Brush Electric Company’s arc light contracts to illuminate major streets and Madison Square Park in 1881. Edison opened the Pearl Street station the following year, introducing the concept of metered power sales for interior lighting and eventually electrically powered equipment. Subsequent development was delayed by political issues until 1888, when Edison opened ‘‘vertical’’ stations in midtown. midtown.

The first competition appeared in 1889 when Westinghouse Electric & Manufacturing Company introduced alternating current (ac) lighting to lower Manhattan through its acquisition of the United Electric Light & Power Company. Despite continued technical problems, Westinghouse and United initiated 60 Hz ac in Manhattan below 59th Street by the end of 1896. At that time, prevailing theory favored direct current (dc) distribution due to power loss in ac distribution systems. However, dc generation was impractical given the limited distribution range of low-voltage dc power. The continued construction of power stations to supply neighborhoods was also economically and logistically impossible. Therefore, the Edison Company began planning for large-scale generation based on 25-Hz ac transmission to local substations, where the voltage was reduced and converted to dc for distribution to customers. United, echoing the belief of Westinghouse, sought to provide a complete ac system and began research in concert with Westinghouse engineers to address the power losses encountered in ac distribution systems.

In 1899, Westinghouse extended its systems beyond Edison’s northern limit at 135th Street to offer ac to customers anywhere on the island. The limitations of the ac motors available at that time, however, discouraged the use of ac by customers. The Edison Company continued to supply 90 percent of the commercial power on Manhattan and constructed the Waterside generating station as a central facility. The expansion of the Edison Company territory was funded by mergers and acquisition of smaller companies, an effort spearheaded by financier Anthony N. Brady with technical direction by Thomas E. Murray. That effort was so successful that within five years the load forecast for ten years was in sight and a second Waterside station was constructed. Thus, an entire industry had been created that was vital to urban life and commerce.

Initial Systems, 1881-1883

Commercial power distribution in Manhattan began formally in June of 1881 when the Brush Electric Company began receiving from the city payment for the arc light illumination of Broadway between Herald Square and Union Square. Power was supplied by a small power station on West 25th Street over a two-wire direct current line energized at 2000 volts (see Fig. 1). Experimental operation for demonstration purposes had begun in late December 1880, with the initial line completed in January 1881. Arc lights were also made available to private customers with large interior spaces, such as hotels and theaters, at the rate of ten dollars per lamp per month. The high cost was offset by the increased income produced by the new attractive appearance. Street lighting also improved the income of stores as signs and window displays were more visible at night.

Additional lamps were installed on a 160-foot tower to illuminate Madison Square Park and reportedly could be seen from New Jersey and Long Island, although the glare from the clustered lamps occasioned complaint from local residents. Arc lights had been considered a civic improvement ever since Father Joseph Neri, S.J., chairman of the physics department at St. Ignatius College in San Francisco, illuminated the adjacent Market Street with his lamps for the nation’s centennial celebration in 1876. Neri predicted that developments in electrical science would revolutionize transportation, commerce and most of daily life within a short time. Arc light systems were installed in public spaces in Wabash, Indiana, and elsewhere but New York City was the first to install a large-scale public lighting system. After the initial Brush installation, plans moved forward rapidly to franchise similar lighting systems on the other major thoroughfares of Manhattan.

Indoor lighting was a different matter. While Brush constructed an additional station to illuminate the docks, warehouses, and piers of the Lower West Side, most rooms required a light that was softer and more comfortable than the harsh glare of an electric arc. The immediate solution appeared in the form of incandescent lighting as developed by several experimenters and brought to a high state of

Fig. 1. Brush Electric’s carbon arc lamps illuminated wealthier districts of Manhattan, like 25th Street and Broadway, shown here in 1881.

practicality by Thomas Edison (see Fig. 2). A number of residences, institutions, and businesses installed Edison lighting plants, but the duplication of boilers, steam engines, and generators made that an expensive and cumbersome approach. Edison determined to make electric lighting affordable to the general populace by development of a distribution system modeled on that of gas light companies. In that scenario, the expense of generation would be distributed across a number of customers to make electric lighting affordable to smaller merchants and residents of the expanding middle class.

Fig. 2. Edison’s pioneering electric lighting station at Pearl Street, ‘‘but a minute’s walk from Fulton Ferry,’’ received a cover story from Scientific American in 1882.

Such a system required development and manufacture of the necessary power conductors, external and internal wiring components, and lamp fixtures. Following the experimental operation of a station at Holborn Viaduct in London, power was first distributed from Edison’s station on Pearl Street in lower Manhattan in the late summer of 1882; metered sales commenced in January 1883 (see Fig. 3). Power consumption was measured through a chemical meter that recorded current flow by electrolytic transfer of metals between plates, which were weighed at 30-day intervals. Power was distributed initially over a two-wire, 110 volt, underground circuit. Pearl Street was the basis for the development of both his ‘‘Village’’ (overhead conductors) and ‘‘City’’ (underground distribution) systems marketed by the Edison Electric Illuminating Companies that were established in municipalities across the nation.

Edison's Expansion, 1883-1891

Edison believed the midtown commercial area to hold the most market potential, but had begun operations in the lower Manhattan financial district for its proximity to the banking houses from which he sought the capital to finance construction. Soon the demand was such that additional ‘‘annex’’ stations were constructed in nearby commercial properties, with steam supplied by an outside vendor.

Distribution of power at 110 volts necessarily entailed high current with a resultant need for cables of substantial, and thus expensive, cross section. John Hopkinson of England had devised a three-wire system that placed two generators in series to double the voltage, with a neutral wire between to provide 110-volt power. The reduced current in the two outside ‘‘legs’’ of the circuit enabled a reduction in cable diameter that effected a 62 percent reduction in copper requirements. The system was developed for Edison by Frank Julian Sprague, later renowned for his electric railway innovations. Sprague also introduced the use of mathematical modeling to system design.

Provision of electric lighting was still an uncertain business and the initial Edison Pearl Street installation did not recover its capital or operational costs during the first two years. The breakthrough came in late 1884 when Sprague placed on the market a practical industrial motor, the first approved by Edison for use on the system.

The sale of power for motors introduced a daytime power load that made Edison’s New York operation profitable in 1885. The Sprague motor also saved from financial collapse numerous other small electric companies that sold incandescent lighting elsewhere. The electric motor simplified industrial plants, which made them both more efficient and safer. The installation of electric motors was made a condition of the settlement of a garment workers strike and thousands were installed within a few years.

Still, there had yet to be any substantive progress in the effort to enter the midtown market, which offered the greatest potential for return on investment. That delay, largely political in origin, blocked the necessary street opening permits required to install the distribution lines, but allowed time for design and devlopment of the ‘‘Vertical Station’’ intended for urban lots where land was at a premium. Instead of the single-level approach in which boilers, steam engines, and generators were placed in ranks, it stacked them to reduce the area required and thus the cost of the property required for a power station. The generators were placed at the street level probably to minimize the length of cable runs while boilers were on an upper floor followed by the coal bunkers above - probably to simplify the distribution of coal by gravity. The concept was adapted to meet the needs of other municipalities where land was expensive near the ideal ‘‘load center’’ of the area to be supplied.

A pair of these stations commenced operation on 26th and 39th Streets in late 1888. With the Sprague distribution improvements in both design and operation - the former with his mathematical modeling, the latter by use of the new three-wire system plus his motor to assure daytime load - the Edison Company had the income potential for continued expansion through the construction of additional stations. The largest in any city at that time was constructed at 55 Duane Street in 1891 to replace the obsolete Pearl Street station. It was followed by plants on East 12th and West 53rd Streets. Those, however, abandoned the vertical format as power demand exceeded the practicality of the arrangement. Large illuminated exterior advertising signs soon joined arc lighting to brighten the street scene and provide additional income in the areas supplied by the new stations.

Fig. 3. Thomas Edison as he appeared in 1890; painting by Alan Archibald Anderson. Smithsonian National Portrait Gallery, Google Cultural Institute.

Thus urban life was transformed as ‘‘night life’’ took on meaning - stores, restaurants, theaters, and sporting events were held at later hours. Broadway would be designated the ‘‘Great White Way’’ in 1902. (Curiously enough, a journalist first gave it that name after a snow storm, alluding to a 1901 book on the Antarctic.) Vestiges of the past still stood, however, for street lights were often dimmed or extinguished entirely in the early hours of the morning.

Competition and the Emergence of Alternating Current Systems, 1888-1891

Edison was not alone in the business; in addition to the arc light companies, several small companies had developed incandescent light businesses. However, the need for capital and the potential revenue had led to the acquisition in 1889 of the Edison Co. by the Consolidated Gas Company of New York, once its bitter rival for lighting business. Con Gas had accepted the obvious superiority of electric illumination over gas mantles and joined in new markets for gas in the fields of heating and cooking. Competition remained, however, for the Edison Company maintained a large electric cookery exhibit in its 55 Duane Street headquarters (see Fig. 4). Still, with Con Gas capital, the Edison Co. took the lead in expansion of the territory supplied.

Fig. 4. The Duane Street station featured an ‘‘electric kitchen’’ in 1896 where a cook offered free lunches prepared with electric appliances to prospective customers to buy the new devices. After finding that most people only ate the lunch, Edison Electric limited free lunches to Fridays for the staff only. 1898 Annual Report, The Edison Electric Illuminating Company of New York, Columbia University Libraries Digital Collection.

The arc and incandescent light companies were almost invariably dc with one major exception that was an unrecognized portent of future trends. The United Electric Light & Power Company, a reorganized arc light company, was acquired in 1889 by the Westinghouse Electric & Manufacturing Company as a means of entry into the Manhattan market. Determined to prove that ac distribution was the most economical and practical system, Westinghouse had developed a complete system based on alternating current (see Fig. 5). Moreover, it was about to enter a public relations battle with Edison and the other dc proponents. United introduced an alternating current system in lower Manhattan in 1889 that distributed power at 133 Hz over single phase lines at 1000 volts. An external transformer at the customer’s premises reduced line voltage to 50 volts, which the company claimed to be safer than the higher 120/240 volts of the Edison three-wire system.

Fig. 5. George Westinghouse oversaw his company’s technical and financial investments in the development of ac power transmission to compete with Edison’s dc system. Photographed by Joseph Gessford about 1907: Library of Congress Prints and Photographs Division.

The installed system worked, but was not a spectacular success and was not an immediate threat to the Edison system. The primary issue was that transformer technology was primitive and that the use of separate transformers for each customer, many of which carried minimal load much of the time, resulted in excessive power losses. Thus, the Westinghouse/United installation was but a minor development on an island dominated by Edison lines and those of a few other localized purveyors of incandescent and arc lighting systems. The Edison Company continued to be the primary electric power company in Manhattan (see Fig. 6).

Fig. 6. After ten years, Edison Electric had extended its system from the Battery to Central Park as indicated by this map of the underground mains. 1893 Annual Report, The Edison Electric Illuminating Company of New York, Columbia University Libraries Digital Collection.

Establishing Edison Electric's Commercial Dominance, 1891-1900

Sprague had been retained by the Edison Company as a consultant in 1886 prior to construction of the vertical stations and his report declared the use of localized or ‘‘neighborhood’’ power stations wasteful and inefficient, as each could supply an area of only three square miles at best. He favored the construction of a large ac station that could transmit power at high voltage throughout the city. Because there was as yet no practical ac motor, he recommended the retention of dc distribution to the customers with the ac reduced in voltage and converted to dc in ‘‘receiving stations.’’ His recommendations were not pursued as considerable research and development expense would have been necessary, while substantial prior investment in dc system development was about to start earning a return.

Five years later, in 1891, as the Duane Street plant went into operation and additional stations were under construction on East 12th and West 53rd Streets, the limitations of the localized dc station were an obstacle to future expansion. In one scenario, 36 stations would be needed to supply the territory south of Central Park, an obvious economic and logistical impossibility. As ac generation and transmission systems improved and practical converters that could supply ac for distribution to customers were developed, the Sprague concept appeared the only practical solution. The major obstacle was economic, for large-scale installations would be expensive.

At that point, leadership shifted from the original inventors and their financiers as Anthony N. Brady, an investor from Albany, NY, began acquiring the franchises of electric and gas utilities in the New York area. Brady was involved in many aspects of urban business, from utility companies to transit lines, and was one of the country’s wealthiest men. His point man in the reorganization of those companies was Thomas E. Murray, a gifted inventor destined to lead the development of utilities in New York City, and who was granted more than 460 patents and contributed many new methods and techniques to the utility industry (see Fig. 7). His initial efforts were directed at the rationalization of the conflicting and often overlapping utility franchises that had been granted to various entrepreneurs in the 1880s. Only through rationalization could he build a customer base of sufficient potential income to amortize the expense of large scale construction.

Fig. 7 Thomas E. Murray designed seven power plants that were the sole source of utility company power for New York City for most of the first half of the 20th century. Photographed in about 1920, courtesy Sean MacGuire, www.temurray.com.

Central AC Generation and Transmission with DC Distribution, 1898-1901

Murray's first effort involved the replacement of inefficient, neighborhood, dc power stations with a central ac station. The development of the Niagara Falls installation proved the practicality and economy of large, central ac stations, and the feasibility of high-voltage ac transmission with underground cables had been demonstrated in London by 1891 by the inventor and ac pioneer Sebastian Ziani de Ferranti at the Deptford Station. Unfortunately that effort was stymied by short-sighted economic decisions in the face of technical difficulties. Still, the distribution problems encountered by ac led many experts to recommend dc, especially in the densely populated areas of cities. The preference for dc was driven also by availability of battery reserve. Battery reserve for peak loads and protection against generation outages became a staple of dc practice in the mid-1890s. The batteries were charged during off-peak hours. Battery reserve thus reduced the capital requirements of a system. The Edison company initiated expansion northward with a battery station on West 53rd Street that was charged from the 39th Street station when loads were not heavy.

Thus, Sprague’s recommendation for the construction of a large central ac generating station and transmission system coupled to a conversion station that distributed dc to customers became a reality. Such conversion stations became known as ‘‘sub’’ or ‘‘distributing’’ stations. Other issues in favor of dc included the comparative performance of ac motors of the period versus those of dc systems, and the fact that dc was already in place. Moreover, dc allowed a simple substitution of utility power for private plants, which were common at that time.

The first application of ac transmission in the Edison Company system involved a tie line between the West 39th and the Duane Street station in 1898 to allow one to support the other at times of peak load. Duane Street experienced a peak around 5 pm as offices closed but stores remained open, while the uptown demand peaked 30 minutes later as restaurants filled prior to the theater hour. The concept had been developed in Chicago to allow closure of downtown stations on weekends and had been installed in Brooklyn at Coney Island as a temporary measure to meet summer demand from ocean-side hotels.

That first Manhattan line, known as the ‘‘Broadway Cable,’’ was intended as the backbone of an ac transmission system that would connect a central ac-generating station to distribution substations that supplied the customers through rotary converters. The development of the rotary converter by Benjamin Lamme at Westinghouse and independently by Charles Bradley simplified greatly the conversion process.

The twenty-year-old Edison Electric Illuminating Co. of New York was formally merged with seven smaller utilities in 1901 to provide the customer base necessary to amortize the investment underwritten by Con Gas. Construction of the central ac station, Waterside, commenced after Murray and his associates revised the original proposals to provide more interior space for components by elimination of the residential apartment towers at the corners that had been intended for the workers and their families. Located between the East River and First Avenue and 38th and 39th Streets, Waterside began operations October 24, 1901 (see Fig. 8). Power was delivered to a series of sixteen new and rebuilt substation facilities that supplied dc to customers throughout the Edison territory south of 135th Street.

Fig. 8. The Edison Electric Company opened the Waterside station at left between 38th and 39th Streets on the East River in 1901 transmitting 6.6 kV, 25 Hz, three-phase ac power to 16 dc conversion stations south of 135th Street in Manhattan. Waterside II on the right was opened in 1906 to meet rising demand. Thomas E. Murray, Electric Power Plants: A Description of a Number of Power Stations (1910).

The concept proved so successful that rate reductions followed rapidly. The result was a dramatic increase in business for the power companies as the reduction in the price of power both stimulated development of all aspects of the electric business and also brought electric power within the means of most residents and businesses. In 1901, power sold at 20 cents per kilowatt hour, a relatively high price that encouraged the use of private stations. In 1898, these numbered 775 in Manhattan and the Bronx. That price was cut by half over the next decade. As a result private stations were retired at the rate of several dozen a year.

Urban AC Systems, 1896-1901

DC distribution continued to dominate the downtown areas of dense concentration of electrical load in Manhattan south of 135th Street, along the waterfront, business center, and older residential areas in Brooklyn. The same was true of similar areas in the cities and large towns across the nation. AC, however, was not overlooked. Proponents claimed that the simplicity of the system of feeders and transformers promised a saving in copper of greater than 500% over that of a similar dc system, with total ac distribution costs reduced by nearly half compared with dc. The United Company completely replaced its system following the development of the Westinghouse polyphase system. This used multiple circuits, or phases, to transmit power more efficiently and operate the new ac induction motor developed by Nikola Tesla, which he licensed to Westinghouse in his package of ac patents. United began operation in 1896 of a 2300 volt, 60 Hz, two-phase Westinghouse distribution system supplied from a rebuilt arc light station on East 29th Street. By 1899, United had extended the lines to the northern end of the island, holding exclusive franchise north of 135th Street, prime residential territory destined for development after the opening of subway access in 1906.

At the start, most United customers were located along the waterfront areas where the early Edison systems had not penetrated due to the low density of potential customers and the proliferation of industrial plants with private generation. That followed an axiom of the General Electric Company’s brilliant engineer and mathematician Charles P. Steinmetz, who stated in 1896 that dc should be employed whenever the load density was sufficient to amortize the expense of substations, with ac restricted to fringe areas. For the next 40 years, power distribution in the downtown areas of cities was primarily in the form of dc.

United became a leader in the advancement of ac distribution even after acquisition by Consolidated Gas in 1900, but it was not merged into the Edison Company at that time. Rather, it remained an independent that shared some facilities with the Edison Co.

United would dominate system development in the future but, as the 20th century dawned, 90 percent of the power sold in New York City was distributed by the Edison company over a three-wire, 120/240 volt, dc system from the 16 conversion substations that were supplied with 6600 V, 25 Hz, three-phase ac power generated at Waterside. Maintenance and daily operation of such a large-scale system was an undertaking in itself, one that required fleets of special motorized trucks to haul cable, supplies, and even the replacement light bulbs which were supplied to customers at no charge until 1915.

As the industry grew, sales of electrical devices spiraled and new marketing venues emerged. Initially, such products were sold only by the offices of the power company. Soon department stores and other merchants offered almost every device imaginable from the usual fans and cooking devices to household cleaning machines, Christmas lights, cigar lighters and even electrically warmed dishpans. Other stores and small entrepreneurs soon followed by selling and servicing electrical products.

Thus, the predictions and objectives of the pioneers were demonstrated in steel and copper. The rapid progress made in urban electrification that began with Brush arc lights on Broadway had in twenty years banished the use of residential and commercial gas lighting, changed the look of cities, and transformed the factory and industrial plants.

Epilog

The use of ac generation with conversion substations to supply dc to customers enabled phenomenal expansion of urban electrification in the first two decades of the twentieth century. It was not without problems, however. By 1915, the heavy copper cables and the substations of dc distribution comprised 50% of the fixed plant investment. Utilities across the nation sought relief in the form of various ac distribution networks that would prove as practical as the dc system. Most municipal utilities had limited their older dc systems to the downtown areas with ac predominant elsewhere. Various schemes were developed to extend ac distribution into those dc zones, but all suffered from limitations in reliability, efficiency, or often both. In 1922 United perfected an automatic ac distribution network that addressed all the issues stymying the distribution of ac to customers in urban areas of dense load concentration.

Six years later, New York Edison reversed policy and adopted the United ac distribution network and began changing over its customers from dc supplied by manually operated substations to ac supplied from simpler automatic distribution networks. By the 1970s, 315 such networks were in operation throughout the United States; at the close of the 20th century, some 350 were in operation around the world. While the operating principles had advanced with time and technological change, the concept of supplanting dc power distribution with ac distribution was rooted in United’s successful innovation of 1922.

Acknowledgements

Timeline

  • 1900, date 1
  • 1902, date 2
  • 1905, date 3

Bibliography

References of Historical Significance

Lamme, B. G. ‘‘Synchronous Motors for Regulation of Power Factor and Line Pressure.’’ A paper presented to a meeting of the American Institute of Electrical Engineers, June 1904.

Murray, Thomas E. Electric Power Plants: A Description of a Number of Power Stations (New York: 1910).

Murray, Thomas E. Power Stations (New York, 1922).

References for Further Reading

Cunningham, Joseph J. New York Power (North Charleston, SC: 2013).

Cunningham, J. J. ‘‘Architect of Power: Thomas E. Murray and New York’s Electrical System,’’ IEEE Power & Energy Magazine 10, no. 2 (March–April 2012), pp. 80–94.

Cunningham, J. J. ‘‘An AC Pioneer: United Electric Light & Power Co.,’’ IEEE Power & Energy Magazine 11, no. 3 (May–June 2013), pp. 84–98; corrections, idem 11, no. 5 (September–October 2013), p. 6–7.

Freedberg, Ernest. The Age of Edison: Electric Light and the Invention of Modern America (New York: 2013).

Hughes, Thomas P. Networks of Power: Electrification in Western Society, 1880–1930 (Baltimore: 1983). Israel, Paul. Edison: A Life of Invention (New York: 1988).

Jones, Payson. A Power History of the Consolidated Edison System, Compiled as a Reference Work from Original Documentary and Other Sources, with Especial Reference to the Menlo Park and Pearl Street Origins of the System (New York: 1940).

Thirty Years of New York, 1882–1912: Being a History of Electrical Development in Manhattan and the Bronx (New York: 1913).

Usselman, Steven W. ‘‘From Novelty to Utility: George Westinghouse and the Business of Innovation during the Age of Edison,’’ Business History Review 66 (Summer 1992), p. 251–304.

About the Author

Joseph J. Cunningham's interests in electric power systems dates to his high school science project, ‘‘The Theory and Operation of Alternating Current,’’ which won a first-place gold medal. This led to a scholarship for the study of physics at St. Francis College. He has researched and authored numerous booklets, articles, and books on topics including industrial electrification, electric utility power systems, and electric rail transportation. He has lectured on and taught the history of electric technology and has consulted on numerous history projects and television productions. His latest book is New York Power (2013).