What is a Combined-Cycle Gas Turbine? Two turbines, one flame

A combined-cycle gas turbine burns natural gas once but extracts electricity in two stages: first from a gas turbine, then from a steam turbine powered by the hot exhaust the first turbine was about to throw away. That simple act of refusing to waste heat is why CCGTs can reach efficiencies around 60%—and why they still matter in a power system filling up with wind, solar, and batteries.
