http://www.exeloncorp.com/corporate/community/b_hist_el... History of Electricity
It was in the late 1870s when America's greatest inventor -- Thomas Alva Edison -- developed and built the first electricity generating plant in New York City.
Electric lighting came to Chicago in 1880, when the Palmer House Hotel installed electric lights in time for that year's Republican National Convention. Later that year in Philadelphia the first electric lights were strung along a ten-block stretch of Chestnut Street. A year later John Wanamaker installed electric lights in his new department store. The age of electricity had arrived!
Soon numerous electric companies were competing to supply power in the nation's major cities. The focus was on business customers, although some wealthy homeowners had electric lighting installed. Because generation capacity was so limited most homes could only have three or four electric lights. And homeowners often had to turn off one light before they could turn on another.
By 1920 all of the nation's major cities had competing electric companies, each with its own sets of poles and wires.