What do you understand by Run-of-river hydroelectricity project? How is it different from any other hydroelectricity project?

Head over storage

Output depends on the drop between intake and turbine, so steep Himalayan rivers suit it, as at Nathpa Jhakri (1,500 MW) on the Satluj.

Flow-dependent output

Generation peaks with snowmelt and monsoon and falls in lean winter months, since there is no large reservoir to store water.

Pondage variant

Some keep a small pond to shift a few hours of flow into peak demand, the limited storage allowed on the Jhelum and Chenab.

Reservoir size

Tehri on the Bhagirathi impounds a large lake that regulates flow across the year, while a run-of-river plant passes water through almost at once.

Submergence and displacement

Tehri submerged old Tehri town, whereas run-of-river projects submerge far less land and displace fewer people.

Multipurpose role

Storage dams like Bhakra also give irrigation and flood control, while run-of-river plants mainly make electricity.

Distinct ecological risk

Tunnels can leave river stretches nearly dry, and the 2021 Chamoli flood destroyed the Rishiganga project.