A pumped storage plant is an economical addition to a system which
increases the load factor of other systems and also provides additional
capacity to meet the peak loads. These have been used widely in Europe,
and about 50 plants are in the US with a total installed capacity of about
6700 MW. In the UK large plants are in operation at Ffestiniog (300 MW)
TYPES OF WATER POWER DEVELOPMENT 501
Fig. 12.4 Storage plant layouts (remote type)
Fig. 12.5 Pumped storage plant