Electric plantIn 1883, the first three-wire central-station incandescent-lighting plant in the U.S. started operations in Sunbury, Pennsylvania built by the Edison Electric Illuminating Co. The plant was a simple wooden structure. An Armington & Sims steam engine drove two 110-volt direct-current generators. The electricity was delivered by overhead wires. Edison had patented his three-wire system on 20 Nov 1882 to supercede the distribution system used at his first commercial central generating station in New York (4 Sep 1882) because it gave savings of over 60 per cent in copper used in conductors. This meant a smaller investment which made it economically possible to build generating plants in many smaller communities.«[Images - top: Sunbury generators at the Edison Ford Museum; bottom: Thomas Edison] |