Why are pumped storage power stations so expensive?

Because it is necessary to pump the water back after use, pumped storage power stations can only provide energy for limited periods of time. In addition they are more expensive to operate than conventional hydroelectric power stations because of their pumping costs.

How pumped storage works?

In water scarce areas, pumped storage schemes are used as an alternative to conventional hydroelectric power stations to provide the power needed during peak periods. Instead of the water being discharged, it is retained in the system and re-used.

What is a pumped storage system?

Instead of the water being discharged, it is retained in the system and re-used. A pumped storage scheme consists of lower and upper reservoirs with a power station/pumping plant between the two.

What is a pumped storage scheme?

Joint ventures between DWA and Eskom resulted in the construction and operation of the Drakensberg and Palmiet Pumped Storage Schemes. In both cases, the powerful pump/turbines installed in the power station are used to pump water up to an elevation from which it can be transferred into a different river catchment.

How does the Drakensberg pumped storage scheme work?

The Drakensberg Pumped Storage Scheme generates electricity during peak periods in its role as a power station, but also functions as a pump station in the Tugela-Vaal Water Transfer Scheme. Water is pumped from the Thukela River, over the Drakensberg escarpment into the Wilge River, a tributary of the Vaal.

How many MW does the Palmiet pumped storage scheme generate?

The scheme was commissioned in 1982 and has a generating capability of 1 000MW. The Palmiet Pumped Storage Scheme transfers water from the Palmiet River catchment into the Steenbras Dam to supplement Cape Town’s water supply. The power station can generate 400MW during peak demand periods and began commercial operation in 1988.