Subject : Power Plant Engineering

Topic: Chap 4- Combined Cycles

Difficulty: Medium

5M

Pumped storage plants are employed at the places where the quantity of water available for power generation is inadequate. Here the water passing through the turbines is store in ‘tail race pond’. During low load periods this water is pumped back to the head reservoir using the extra energy available. This water can be again used for generating power during peak load periods.

Pumping of water may be done seasonally or daily depending upon the conditions of the site and the nature of the load on the plant. Such plants are usually interconnected with steam or diesel engine pants so that off peak capacity of interconnecting stations is used in pumping water and the same is used during peak load periods.

Of course, the energy available from the quantity of water pumped water the power available is reduced on account of losses occurring in prime movers.