Steam turbines and thermal power plants
Boilers raise steam that spins turbines, in coal, oil, nuclear, biomass and waste plants.
Conversion and use · Conversion devices · No. 96
- Conversion and use
Most of the world's coal and nuclear power still comes from boiling water, and two thirds of the heat goes to waste.
Chart: Illustration: Steam turbines and thermal power plants
Where it comes from
Chart: Map of where it comes from
Burning fuel or splitting atoms boils water into steam at very high pressure, which spins a turbine before being condensed and pumped back.
Three things to know
- The average US coal plant turns only about 32% of its coal's energy into electricity (calculated, 2025).
- Even a perfect engine with 600 C steam and a 30 C condenser could convert at most about 65% of the heat (calculated).
- For a new coal plant, paying back the capital is about 69% of the cost per MWh, while coal is only about 15% (calculated).
The journey
- 1 Fuel or heatCoal, oil, biomass, waste or reactor
- 2 BoilerWater turned to high-pressure steam
- 3 TurbineExpanding steam spins the shaft
- 4 GeneratorUp to 99% of shaft power made electric
- 5 CondenserMost leftover heat dumped to cooling water