CCGT Economics
Prerequisites
Natural gas now generates more U.S. electricity than any other single source. The financial logic of the plant that made this possible reveals something counterintuitive: the cheapest-to-build power plant is often also the cheapest to operate.
CCGT economics refers to the cost structure that makes combined-cycle gas turbines the dominant choice for new dispatchable power plant investment: low capital cost per kilowatt, short construction timelines, high fuel efficiency, and operational flexibility that lets plant owners match output to price signals.
Capital costs run roughly $1,000-2,100 per kilowatt of capacity (2024 estimates), compared to roughly $7,500-8,000/kW for nuclear and $7,000-7,500/kW for coal with carbon capture (EIA/Sargent & Lundy 2023 capital cost estimates). A CCGT can be permitted and built in two to three years, which substantially reduces financing risk because the plant begins earning revenue before interest compounds for a decade.
Fuel cost is where efficiency pays off. CCGTs convert 60-63% of gas to electricity, so they need less fuel per megawatt-hour than any other gas technology. When U.S. shale production pushed Henry Hub prices below $3/MMBtu in the 2010s, CCGT plants generated electricity for $35-55/MWh all-in. Simple-cycle peakers running at 35% efficiency consumed nearly twice as much gas per MWh, which is why cheap gas knocked them down the dispatch stack.
If CCGTs can ramp from minimum output to full power in 30-60 minutes, what does that capability allow operators to do in a grid with growing solar?
Operators can back down during midday hours when solar floods the grid with cheap electrons, then ramp back up at evening peak when solar fades and prices spike. This flexibility repositions CCGTs from baseload competitors to reliability assets that complement intermittent renewables.
The same flexibility that makes CCGTs economically attractive also raises a policy question: whether gas plants built to run frequently will instead sit idle most of the year, and what that does to project economics.
Which combination of factors most directly explains why CCGTs displaced coal as the dominant new-build generation technology in the United States after 2010?
No federal coal ban existed. The shift was economic: cheap shale gas, faster and cheaper construction, and superior thermal efficiency made CCGTs the dominant choice in competitive power markets.
The answer is DLesson complete
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