• Coal is conveyed from an external stack, ground to a very fine powder by large pulverizers and mixed with preheated air.
  • The steam is piped to the high-pressure turbine, where it is reduced in both pressure and temperature before being returned to the boiler reheater.
  • The three-phase electrical generator generates an intermediate level voltage (typically 20-25 kV), which is then stepped up by a unit transformer to a voltage more suitable for transmission (typically 250-500 kV) and is sent out onto the transmission system.
  • The exiting steam, now a little above its boiling point, is brought into contact with cold water (pumped in from the cooling tower) in the condenser, where it condenses rapidly back into water.
  • The feed pump passed the condensed water through a de-aerator, and pre-warmed before being returned to the boiler drum.
  • The cooling tower acts like a chimney as the warm air rises to the top and draws cool air in the bottom.
  • The warmed circulating water passes through the pipes and is pumped to the cooling tower where its cooled and returned to the condenser.
  • Pumps the water from the makeup pond to the cooling tower.
  • Exhaust gas from the boiler is drawn through an electrostatic precipitator— a highly efficient filtration device that removes particles from the gas — and then into the scrubber to remove sulfur dioxide (SO2) before it is vented through the chimney stack.
  • The hot air-fuel mixture is forced into the boiler where it rapidly ignites.
  • Water of a high purity flows vertically up the tube-lined walls of the boiler, where it turns into steam, and is passed to the boiler drum, where steam is separated from any remaining water.
  • The cooling water from the condenser is sprayed inside a cooling tower, creating a highly visible plume of water vapor, before being pumped back to the condenser in the cooling water cycle.

Getting Started

Coal is the most abundant fossil fuel resource in the United States, providing more than half of the electricity we use today. Press the orange pumps to discover how a power plant turns coal into energy. For additional information, click the Hotspots.