A turbine that burns gaseous fuel, and the resulting hot gas drives the blades of the turbine, which generate electricity or propel a vehicle. The intake air is compressed in a compressor and fed into a combustion chamber, where the fuel is injected. This is burned, and the resulting hot gas drives the turbine. Part of the turbine’s energy is used to drive the compressor; the rest can be used for propulsion (if the gas turbine is installed in an aircraft, for example) or to spin a generator and generate electricity. Gas turbine power plants use natural gas, biogas, or syngas produced from biomass as fuel. Combined-cycle power plants use a gas turbine in tandem with a steam turbine to increase their efficiency.