thomas edison > a lifetime of invention : inventing the incandescent lamp
thomas edison > inventing the incandescent lamp : battle of the currents


Battle of the Currents

The battle of the currents ignited in March 1886 in Great Barrington, MA when William Stanley installed the first commercial alternating current (AC) electrical system, which featured the first practical transformer.  The industrialist George Westinghouse had hired Stanley to experiment with transformers.  The transformer permits the voltage in an AC system to be increased or decreased and permitted higher voltages for long-distance electrical transmissions that could be stepped down to lower voltages for use in businesses and homes.  An Edison system using direct current (DC), could not supply an area greater than sixteen square miles, severely limiting its long-term viability.  Imagine having power stations every four miles!

The inventor Elihu Thomson placed an AC system on the market the following year.  He had held back on commercializing his system until he had developed protective devices to prevent homeowners from receiving shocks.

Thomas Edison was opposed to AC.  Among other things, he believed it was too dangerous, and campaigned against AC because of his safety concerns.  Westinghouse disagreed with Edison and believed the safety concerns were exaggerated.  Edison and his associates attacked AC and developed a marketing campaign against it.  The campaign included promoting AC for use in an electric chair at the state prison in Auburn, NY.  According to Edison’s men, the prisoner was not electrocuted – instead he was “Westinghoused.”

Despite Edison’s campaign, electrical customers began to prefer the AC systems.  Both George Westinghouse’s system, with its transformer developed by Stanley and AC generator developed by Nikola Tesla, and Elihu Thomson’s system gained popularity over Edison’s DC system, setting the stage for the formation of General Electric.


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