The condenser is the heat sink for steam power plant. The condensation process is accomplished by the transfer of heat from the steam exhausting from the turbine to the water used for cooling.
Steam is condensed at substantially constant pressure and its heat content (enthalpy), which is given up, raises the temperature of the cooling water as it flows through the tubes (Fig 4.12). Referring to Fig 4.13, which illustrates a basic heat flow diagram, there are three factors which determine the enthalpy of the steam at the turbine exhaust:
- The conditions and heat content of the steam leaving the boiler.
- The efficiency of the turbine in converting this heat energy into work.
- The selected heat sink temperature.