What if hydropower dams were all replaced by small hydro plants? [05]
Hydropower remains the largest single source of renewable electricity worldwide , supplying ~14% of global power and anchoring system flexibility in more than 150 countries. The fleet surpassed ~1.25–1.41 TW of installed capacity by end‑2024, with pumped storage providing >90% of long‑duration energy storage globally. [hydropower.org] , [iea.org] , [hydropower.org] Small hydro (typically <10–50 MW, often run‑of‑river) offers low‑impact, distributed generation with sizable untapped potential (~222 GW identified by UNIDO/ICSHP), but today totals only ~79 GW. If we hypothetically replaced large dams with only small hydro , three structural consequences follow: [renewablee...yworld.com] Massive loss of storage and seasonal flexibility. Reservoir hydropower and pumped storage underpin diurnal and seasonal balancing —capabilities small run‑of‑river projects largely lack. Without this, grids would need trillions of dollars of alternative storage, transmission, and firm capacity. [iea...