Hydrocarbons are compounds made of carbon and hydrogen atoms, and fuels are mostly made up of different hydrocarbons. Many hydrocarbons are also volatile organic compounds (VOCs). Hydrocarbon emissions from gas turbines are a concern because volatile hydrocarbons can contribute to the formation of ozone (O 3).

The potential sources of hydrocarbons from gas turbines are from the storage of fuel for a gas turbine and unburned hydrocarbons from the exhaust. Emissions of unburned hydrocarbons from gas turbines are very low and most of the hydrocarbons that make up natural gas are not considered to be ozone precursors.