Duke Energy Ohio, Inc. (Duke Energy Ohio) is engaged in the generation, transmission and distribution of electricity; and sale and transportation of natural gas and energy marketing. The company generates electricity from coal-fired, natural gas fired, combined cycle, and combustion turbine power plants. Duke Energy Ohio has a total generation capacity of 8,589 MW. It distributes electricity over 2,500 miles of transmission lines, 19,500 miles of distribution lines and 280 substations. It distributes gas over 7,100 miles of gas mains. The company serves 820,000 electric customers and 500,000 natural gas customers. Duke Energy Ohio operates in the Southwestern portion of Ohio, Illinois, Indiana and Pennsylvania. The company through its subsidiary Duke Energy Kentucky, Inc. operates across Kentucky. It is a subsidiary of Cinergy Corp. Duke Energy Ohio operates in two business segments namely, Franchised Electric and Gas, and Commercial Power. The company is headquartered in Ohio, the US.