Explore terms related to combustion turbines and the environment
A combustion turbine converts fuel such as gas into mechanical power. Combustion turbines in the power sector produce electricity; those in the industrial sector drive mechanics for chemical or manufacturing plants, and may also be used to generate power or heat.
A single combustion turbine unit is located within a larger power plant or facility. One power plant can house multiple combustion turbine units. Some pollution standards apply based on unit characteristics, while others apply based on plant characteristics.
There are two types of turbine configurations: combined-cycle units and simple-cycle units. These units are used in both the power sector and industrial sector. Combined-cycle units are typically larger, fuel-efficient units that run more often. They include a heat recovery steam generator, which allows them to be more efficient. Simple-cycle units are typically smaller, less fuel-efficient units that run less often. This fuel-inefficiency means simple-cycle units produce more pollution per unit of electricity generated compared to combined-cycle units. Some pollution standards are based on use of combined-cycle or simple-cycle mode.
Capacity is the maximum electricity output a power sector unit or plant can produce per hour. Capacity factor is the total electric output of a unit or plant relative to the unit or plant’s maximum output—for example, a unit operating at 30% capacity factor would produce 30% of the electricity it could have produced over a specified time period if operating at its maximum rated capacity. Some pollution standards apply based on a unit or plant’s capacity factor.
Generation is how much electricity is produced by a unit or plant in a given time.
Consumption is how much gas a unit or plant consumed over a period of time. These measurements together can indicate fuel-efficiency.
Heat-rate indicates the amount of fuel required at a unit or plant to generate one unit of electricity.
Percent people of color is defined, per EPA, as the percent of individuals in a block group who list their racial status as a race other than white alone and/or list their ethnicity as Hispanic or Latino. That is, all people other than non-Hispanic white-alone individuals. The word “alone” in this case indicates that the person is of a single race, not multiracial.
Percent low-income is defined, per EPA, as the percent of a block group’s population in households where the household income is less than or equal to twice the federal poverty level.
EJ populations are defined, per EPA, as the highest intersection of low-income populations, people of color, and a given environmental indicator, such as ozone level in the air.