Changes

In 1878-81 Edison was at the peak of his intellectual powers. He sought solutions to technological problems through scientific investigations, experimented with multiple ways of technical problem solving, calculated costs and pricing, established methods of production, evaluated the character of potential business partners, negotiated contracts and business partnerships one day and raved back to the lab to scrutinize technical details the next.  

In 1878-81 Edison was at the peak of his intellectual powers. He sought solutions to technological problems through scientific investigations, experimented with multiple ways of technical problem solving, calculated costs and pricing, established methods of production, evaluated the character of potential business partners, negotiated contracts and business partnerships one day and raved back to the lab to scrutinize technical details the next.  

===Generating electricity===

===Generating electricity===

[[Image:Edison-pearl-street.jpg|thumb|330px|Model of Pearl Street generating plant]]  Edison's development of central-station lighting systems for cities was one of the great achievements in world history because it brought electricity out of the laboratory into actual commercial use. His Pearl Street (New York City) electricity generating station introduced four key elements of a modern electric utility system: reliable central generation, efficient distribution, a successful end use (in 1882, the light bulb), and a competitive price. It was a model of efficiency for its time. At first it served 59 customers for about 24 cents per kilowatt hour. By the late 1880s, power demand for electric motors (especially for elevators and streetcars) brought the industry from mainly nighttime lighting to 24-hour service and dramatically raised electricity demand for transportation and industry needs. By the end of the 1880s, small central stations dotted many U.S. cities; each was limited to a few blocks area because of transmission inefficiencies of direct current (DC).  Edison fought a mighty battle with [[George Westinghouse]], who developed a competing system based on alternating current (AC).

[[Image:Edison-pearl-street.jpg|thumb|330px|Model of Pearl Street generating plant]]  Edison's development of central-station lighting systems for cities was one of the great achievements in world history because it brought electricity out of the laboratory into actual commercial use. His Pearl Street (New York City) electricity generating station introduced four key elements of a modern electric utility system: reliable central generation, efficient distribution, a successful end use (in 1882, the light bulb), and a competitive price. It was a model of efficiency for its time. At first it served 59 customers for about 24 cents per kilowatt hour. By the late 1880s, power demand for electric motors (especially for elevators and streetcars) brought the industry from mainly nighttime lighting to 24-hour service and dramatically raised electricity demand for transportation and industry needs. By the end of the 1880s, small central stations dotted many U.S. cities; each was limited to a few blocks area because of transmission inefficiencies of direct current (DC).  Edison fought a mighty battle with [[George Westinghouse]], who developed a competing system based on alternating current (AC), which was first invented by [[Nikola Tesla]].

==Entrepreneur==

==Entrepreneur==