Working fluid cycle steam power plant is a closed cycle, which uses the same fluid repeatedly. First, the water is filled into the boiler to fill the entire surface area of heat transfer. In the boiler water is heated by the hot gases of combustion fuel with air so that turned into vapor phase. Steam produced by boiler with pressure and temperature are directed to do work on the turbine to produce mechanical power in the form of rotation.
The former steam out of the turbine, and then flowed into the condenser to be cooled with cooling water that turned to water. Condensate water is then used again as boiler feed water. Thus the cycle goes on and repeats.
Rotation of turbine is used to turn a generator that is coupled directly to the turbine. So when the turbine rotates, the generator output terminals generate electricity. Although working fluid cycle is a closed cycle, but the amount of water in the cycle would decrease. The reduction is due to the leakage of water either intentional or unintentional