NiSource Inc., an energy holding company, provides natural gas, electricity, and other products and services in the United States. The company offers natural gas service and transportation to residential, commercial, and industrial customers; generates, transmits, and distributes electricity; and provides wholesale and transmission transaction services. It serves approximately 3.5 million natural gas customers and 500,000 electric customers in in Ohio, Pennsylvania, Virginia, Kentucky, Maryland, Indiana, and Massachusetts. The company also operates 3 coal-fired electric generating stations with a net capability of 2,540 megawatts (MW), 3 gas-fired generating units with a net capability of 196 MW, and 2 hydroelectric generating plants with a net capability of 10 MW, as well as a combined cycle gas turbine plant with a capacity of 535 MW. The company was formerly known as NIPSCO Industries, Inc. and changed its name to NiSource Inc. in April 1999. NiSource Inc. was founded in 1912 and is headquartered in Merrillville, Indiana.