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Electricity storage that pumps water uphill and later generates power as the water flows down through turbines.
Save conceptPumped-storage hydropower stores energy by moving water to a higher reservoir. When the system generates, water runs back down through turbines connected to generators. It is a storage technology, even though the generating equipment resembles a conventional hydropower station. The electricity used to pump is part of its energy balance.
The operator uses electricity to pump water uphill when supply is available. It releases water when electricity is needed. Reversible machinery can act as both pump and turbine, depending on operating mode. The reservoirs, height difference, water volume and equipment ratings affect how much energy can be stored and how quickly it can be delivered.
Imagine a scheme receives 100 units of electricity to pump water upward and later delivers 80 units during a busy evening. The illustrative round-trip efficiency is 80%. Those figures are hypothetical, not Tubatse specifications. The economic use depends on shifting energy to a useful period and providing system services; it does not require claiming that storage creates additional energy.
A power rating describes how quickly the facility can deliver electricity. Energy storage describes how much it can deliver over time. A reservoir can therefore support a rated output for a limited duration. Pumped storage is also different from a conventional dam that primarily generates from naturally arriving river water rather than a repeated pumping cycle.
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