• A heat engine is any device that converts heat energy in to useful macroscopic work.
  

W	= Net Work Output of the Heat Engine.
Qh	= Heat Input to the Heat Engine.
Ql	= Heat Exhausted from the Heat Engine.

Conservation of Energy: (First Law of thermodynamics)

Pump: Water is pumped into a boiler at high pressure.

Boiler: Water exits the boiler as a superheated, high-pressure steam. Energy used to fire the boiler represents the main cost.

Turbine: The high pressure steam turns a turbine to extract mechanical work. Some of this work is also used to run the pump.

Condenser: Heat is removed from the water vapor exiting the turbine by a river or a cooling tower, condensing the vapor to a liquid.