1. Gas turbines Newer type of internal combustion engine.
Used in jets and some electric power plants
Air pulled in the front and compressed in a compressor. (The rotating fan-like structure you see when you look into a jet engine).
Air is mixed with fuel and ignited, this heated mixture expands.
Expanding gas moves through the turbine, which is connected to the compressor by a rotating shaft.
Hot gases are expelled with a greater velocity than the intake air, giving the engine is thrust.

2. Gas Turbines
For electricity generation, the power output turbine turns the shaft.
For aircraft, the gas is expelled out the jet nozzle.

3. Gas Turbines
20-30% efficiency converting thermal energy to mechanical energy
Lightweight
Respond quickly to changing power demands
Relatively cheap for public utilities
Limitations are the need for materials to withstand T~ 1000 C and the high rotation speeds