The gas turbine is the most satisfactory way of producing very large power in a self-contained and compact unit. The gas turbine obtains its power by utilising the energy of a jet or burnt gases and air, the velocity of the jet being absorbed as it flows over several rings of moving blades which are fixed to a common shaft. The gas turbine requires an air compressor which is driven off its own shafting. This absorbs a considerable proportion of the power produced and thus lowers the overall efficiency, which is of the order of 20%–30%.
The following are the major fields of application of gas turbines: