Illuminated, Sept 4, 1882
Thomas Edison’s Edison Illuminating Company flipped the switch on his power station on Pearl Street in lower Manhattan, at 3pm, the 106 lamps located at JP Morgan's Drexel Bank office lit up. So did the New York Times and the other nearby buildings. All power was underground which took about a year to install. By the end of the month, they had 59 customers. By the next year, they had 513.