What is Pumped Storage Hydropower (PSH)?

About Pumped Storage Hydropower (PSH):

• It is a type of hydroelectric energy storage.
• It is a fundamentally simple system that consists of two water reservoirs at different elevations.
• Working:
  • When there is excess electricity available, such as during off-peak hours or from renewable sources like solar and wind, it is used to pump water from the lower reservoir to the upper reservoir.
  • When there is a demand for electricity, the water is released from the upper reservoir back down to the lower reservoir, passing through turbines that generate electricity.
  • The system also requires power as it pumps water back into the upper reservoir (recharge). 
• PSH plants operate much like conventional hydropower plants, except PSH has the ability to use the same water over and over again. 
• The technologyabsorbs surplus energy at times of low demand and releases it when demand is high.
• The energy storage capacity of a PSH depends on the size of its two reservoirs, while the amount of power generated is linked to the size of the turbine.
• There are two main types of PSH:
  • Open-loop:with either an upper or lower reservoir that is continuously connected to a naturally flowing water source such as a river.
  • Closed-loop:an ‘off-river’ site that produces power from water pumped to an upper reservoir without a significant natural inflow.