About this lesson
A combined-cycle plant puts a Brayton (gas turbine) cycle on top of a Rankine (steam) cycle. The hot exhaust of the gas turbine makes the steam, so far less fuel energy is wasted.
How it works
- The gas turbine burns fuel and drives a generator.
- Its exhaust, still very hot, passes through a heat recovery steam generator (HRSG).
- The HRSG turns feed water into steam using that exhaust heat, with no extra fuel.
- The steam drives a steam turbine and a second generator.
- The exhaust steam is condensed and returned to the HRSG.