Choose State Change Location

Introduction Oil- and Gas-Fired Combustion Turbines

Duke Energy operates a system of generating plants fueled by oil or natural gas, including combustion turbines, combined-cycle units and oil-fired units.

Combustion Turbines

Many of our combustion turbine units are used to supplement power supply during peak demand periods when electricity use is highest. Like hydroelectric stations, combustion turbine units start quickly. They can be used for a short time to meet temporary energy demands, but are also capable of operating for extended periods. Combustion turbine units can operate together or independently.

How Do Combustion Turbines Work?

Natural Gas Combined Cycle

A combined-cycle generating plant primarily uses combustion turbines, heat-recovery steam generators (or boilers), and steam turbines to convert natural gas fuel to electricity. Natural gas is burned in the combustion turbines to produce mechanical power that is converted to electric power by the generators. For increased efficiency, the hot exhaust gases resulting from this combustion process are routed through the boiler, which produces steam and additional electricity. Combined-cycle units offer greater efficiency than traditional combustion turbines, and their operational flexibility is vital in supporting intermediate load demand.


Oil-fired generating plants burn oil to produce electricity. They are similar in construction and operation to coal-fired and natural gas-fired facilities.