Due to electric utility deregulation in Michigan, DTE Energy was forced to sell off Detroit Edison's sister subsidiary involved in high-voltage energy transmission: International Transmission Co. (ITC)
Detroit Edison's near 11-gigawatt generating capacity is offered to its 7,600-square-mile (20,000 km2) service area, which encompasses 13 counties in the southeastern portion of Michigan's lower peninsula. Energy is distributed throughout Huron, Tuscola, Sanilac, Saint Clair, Lapeer, Livingston, Ingham, Oakland, Macomb, Wayne, Washtenaw, Lenawee and Monroe counties by over a million utility poles and 44,000 miles (71,000 km) of power lines.
Detroit Edison's distribution line voltages are three-phase 4,800 volts (Delta) 4,800/8,320 volts (wye) and 7,620/13,200 volts (Wye) . All new distribution circuits constructed after 1959 are 13,200 volts. The 8,320 volt distribution lines are located in Pontiac, Michigan in an area that was served by Consumers Power Company until the mid 1980's when the area was acquired by Detroit Edison.