DC Power: Not Just for the Energizer Bunny Anymore
During the late 1800s Thomas Edison and George Westinghouse were engaged in an intense industrial rivalry. Edison's electrical inventions ran on DC (direct current). Westinghouse tried to convince governments and business that AC (alternating current) was the way to go for the development of large-scale power distribution systems. In their book American Entrepreneur: The Fascinating Stories of the People Who Defined Business in the United States, Larry Schweikart and Lynne Pierson Doti retell how the battle got pretty nasty.
"Edison's company enthusiastically publicized accidents from AC voltage, to the point of conducting experiments in which cats were electrocuted to show its dangers. Newspapers cooperated with stories whose headlines read 'Electric Wire Slaughter' and 'Another Lineman Roasted to Death.' After the State of New York adopted electrocution (using AC) as its means of capital punishment, Edison officials referred to it as 'Westinghousing' the condemned."
"Then in 1892, Westinghouse's company won the competition to provide the lighting for the Chicago Columbian Exposition, proving to the world the safety and efficiency of AC power. That was the break that Westinghouse needed, and contracts to provide electricity to homes and businesses flooded Westinghouse Electric."
Throughout the twentieth century, AC transmission and distribution systems spread around the world and DC power, when required to operate something, was either provided through the use of a power-consuming transformer or by a relatively small DC storage device — a battery. In recent years, though, DC has been coming back into prominence.
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