NiSource is an energy holding company that operates as a regulated natural gas and electric utility company. It operates through two segments, Gas Distribution Operations and Electric Operations. The company provides natural gas service and transportation to residential, commercial, and industrial customers, generates, transmits, and distributes electricity, and provides wholesale and transmission transaction services. It also owns and operates three coal-fired electric generating stations, three gas-fired generating units, and two hydroelectric generating plants, as well as a combined cycle gas turbine plant.