Alternative uses of gas turbine exhaust heatA gas turbine drives a generator. Simple-cycle operation releases its exhaust without steam generation. Combined-cycle operation adds a heat recovery boiler, a steam turbine and another generator to produce additional electricity. These are alternatives, not simultaneous branches.Gas turbineAir and fuel enterGeneratorshaftElectricityHot exhaustTwo alternative arrangementsSimple cycleCombined cycleExhaust leaveswithout generatingsteam for powerHeat recoverysteam generatorSteam turbine+ generatorAdditionalelectricitySteam

Recovering exhaust heat requires additional equipment. A machine’s previous ownership does not tell us whether that equipment is present.

Simplified energy paths. Exhaust still leaves a combined-cycle plant; cooling systems, condensers and emissions controls are omitted. No project configuration or efficiency is assumed.