Correct Option (c)
Pumped-storage hydropower (PSH) is a well-established mechanical energy storage technology. It involves two water reservoirs situated at different elevations. During periods of low electricity demand or surplus generation, electricity from the grid is utilized to pump water from the lower reservoir to the upper reservoir, storing energy as gravitational potential energy. When electricity demand is high, the stored water is released from the upper reservoir, flowing through turbines to generate electricity. PSH is thus a crucial method for long-duration energy storage, facilitating grid stability and balancing electricity supply with demand.
Incorrect Options
Irrigation of terraced crop fields (a): This practice pertains to water management for agricultural cultivation on sloped land. It does not involve the principles of electricity storage, turbine-based generation, or grid integration that characterize pumped-storage hydropower.
Lift irrigation of cereal crops (b): Lift irrigation systems are designed to elevate water from a source to higher agricultural fields for irrigation purposes. While it involves lifting water, its primary function is water delivery for crops, not the storage and subsequent generation of grid-scale electrical energy through potential energy differences.
Rainwater harvesting system (d): Rainwater harvesting focuses on collecting and storing precipitation for various uses, such as domestic supply, groundwater recharge, or small-scale irrigation. It is unrelated to the large-scale energy storage and electricity generation capabilities inherent in pumped-storage hydropower.