Recently, the term "pumped-storage hydropower" is actually and appropriately discussed in the context of which one of the following?

(a) Irrigation of terraced crop fields
(b) Lift irrigation of cereal crops
(c) Long duration energy storage
(d) Rainwater harvesting system

Correct Answer: (c) Long duration energy storage

Explanation:

Pumped-storage hydropower (PSH) is primarily discussed in the context of long duration energy storage. It stores energy by pumping water from a lower reservoir to a higher one when there is excess electricity, and releases it to generate power during high demand periods .

Analysis of other Options:

(a) Irrigation of terraced crop fields: PSH is not typically used for irrigation purposes. It is designed for energy storage and grid management, not for agricultural irrigation .
(b) Lift irrigation of cereal crops: Similar to the previous point, PSH is not used for lift irrigation. Its primary function is to store and generate electricity, not to pump water for crop irrigation .
(d) Rainwater harvesting system: While rainwater harvesting involves storing water, it is not the same as PSH. Rainwater harvesting is for water conservation and usage, whereas PSH is for energy storage and grid stability .

Learn more

Definition: Pumped-storage hydropower (PSH) is a type of hydroelectric energy storage that uses two water reservoirs at different elevations to store and generate electricity .
Working Principle:
- Energy Storage: Water is pumped from a lower reservoir to an upper reservoir using surplus electricity during low demand periods.
- Energy Generation: During high demand, water is released back to the lower reservoir through turbines, generating electricity .
Efficiency: The round-trip energy efficiency of PSH ranges from 70% to 80%, with some sources claiming up to 87%.
Global Usage: PSH accounts for over 90% of grid-scale energy storage capacity worldwide, with significant installations in the United States, China, and Japan .
Types:
- Open-Loop PSH: Connected to natural water bodies.
- Closed-Loop PSH: Independent of natural water bodies, relying on man-made reservoirs .
Historical Context: The first PSH systems were developed in the 1890s in Italy and Switzerland. The technology has evolved significantly since then, with modern systems incorporating advanced reversible turbines .
Applications:
- Grid Stability: Balances supply and demand, especially with the integration of intermittent renewable energy sources like wind and solar.
- Peak Shaving: Provides electricity during peak demand periods, reducing the need for additional power plants .
Environmental Impact: While PSH is a clean energy technology, it can have ecological impacts, particularly on local water bodies and ecosystems. Careful site selection and management are crucial.
Future Prospects: As renewable energy sources become more prevalent, the role of PSH in providing long-duration energy storage and grid stability is expected to grow .