Potentials and challenges of hydropower

Potential

• Nepal: about 83,000 MW theoretical potential and about 42,000 MW economically feasible, thanks to steep rivers (Koshi, Gandaki, Karnali, Mahakali) with Himalayan snow and monsoon rainfall. Installed capacity is above 3,000 MW and is growing (about 3,500 MW or more by 2025), with the Upper Tamakoshi (456 MW) and Kaligandaki A (144 MW) among the large projects.
• Clean, renewable, low operating cost, long life (50+ years), and storable (reservoirs) for peaking.
• Export potential to India and Bangladesh, and basis for industry and electric cooking and transport.
• Multi-purpose benefits: irrigation, flood control, water supply, tourism.

Challenges

1. High capital cost and long construction time; financing difficulties.
2. Difficult geology and terrain: landslides, floods, glacial lake outburst floods (GLOF) and earthquakes (2015 Gorkha earthquake damaged plants).
3. Seasonal variation: high monsoon flow and low dry-season flow, so wet-season surplus and winter shortage; shortage of storage projects.
4. Environmental and social impacts: displacement, loss of land and forest, sediment, effect on aquatic life.
5. Transmission and distribution: weak transmission lines, delays in grid connection, and losses.
6. Policy and governance: delay in licences, land acquisition, PPAs, political issues, and regional trade agreements.
7. Climate change: changing glaciers and rainfall patterns.
8. Sediment erosion of turbines.

Solutions: storage and pumped-storage projects, sound planning with EIA, early community involvement and benefit sharing, and regional power trade.