国际能源署-气候对南亚和东南亚水电站的影响（英）-2021.12-68页_4mb

Summary of Climate Impacts on South and Southeast Asian Hydropower

Core Content

This report by the International Energy Agency (IEA) examines the impact of climate change on hydropower in South and Southeast Asia, focusing on the region's growing reliance on hydropower for electricity generation and the challenges posed by climate change. Hydropower accounts for 14.5% of the region’s total electricity generation, with an installed capacity of 117 GW as of 2020. In countries like Bhutan and Nepal, it represents over 90% of electricity generation. The report highlights the need for climate resilience measures to safeguard hydropower infrastructure and operations from the adverse effects of climate change.

Main Views

• Climate change poses significant risks to hydropower systems in South and Southeast Asia, including rising temperatures, extreme rainfall, glacial melt, and more frequent extreme weather events.
• Hydropower capacity factors are projected to decline across the region due to changing climate conditions, with the most severe declines expected in the Indian Subcontinent and Mainland Southeast Asia.
• Climate resilience is essential for the continued operation and expansion of hydropower projects, especially as these systems are expected to face more frequent and intense climate-related hazards.
• Regional cooperation is necessary to manage transboundary water resources and coordinate climate adaptation strategies across countries sharing major river basins.

Key Information

Current Hydropower Status

• Total installed capacity: 117 GW (2020), accounting for 9% of global hydropower capacity.
• Contribution to electricity generation: 14.5% in South and Southeast Asia.
• Country-specific data: Bhutan and Nepal rely heavily on hydropower (over 90% of their electricity generation).
• Growth projections: Hydropower is expected to expand further to meet rising electricity demand and support clean energy transitions.

Climate Impacts

• Rising temperatures: Asia has warmed by 1.39°C above the 1981-2010 average by 2020, with projections of up to 4°C by 2100 under high GHG emission scenarios.
• Extreme weather events: Increased frequency and intensity of floods, landslides, and tropical cyclones are expected to disrupt hydropower projects and operations.
• Glacial melt: The Hindu Kush Himalayan region, a key source of water for major rivers, is experiencing accelerated glacier retreat and increased glacial lake outburst floods (GLOFs), which have already caused damage to several hydropower projects.

Climate Scenarios

• The report evaluates three GHG concentration scenarios:
  • Below 2°C: Projected decrease in regional mean hydropower capacity factor by 4.6% (2020–2059).
  • Around 3°C: Projected decrease by 5.1% (2020–2059) and 5.4% (2060–2099).
  • Above 4°C: Projected decrease by 6.8% (Indian Subcontinent) and 8.2% (Mainland Southeast Asia) by 2100.

Regional Variations

• Indian Subcontinent: Expected to see a continuous decline in hydropower capacity factor.
• Mainland Southeast Asia: Also projected to experience a consistent decrease in capacity factor.
• Maritime Continent (Indonesia, Malaysia, Philippines): Shows a drop in 2020–2059, followed by recovery in 2060–2099.
• Himalayan region (Bhutan, Nepal): Exhibits similar trends to the Maritime Continent, with a potential recovery in later decades.

Climate Resilience Measures

• Build robust climate databases: To better understand and assess climate impacts on hydropower.
• Integrate climate resilience into planning and construction: To ensure new projects are designed to withstand future climate conditions.
• Enhance operation and maintenance strategies: Including regular monitoring, risk assessment updates, and emergency response planning.
• Strengthen regional cooperation: To manage shared water resources and coordinate climate adaptation efforts.

Conclusion

The report underscores the importance of climate resilience in hydropower systems as the region continues to expand its hydropower capacity. While climate change presents significant challenges, particularly in the form of extreme weather and glacial melt, it also highlights the potential for resilient hydropower systems to support the transition to clean energy and improve the reliability of electricity services. The IEA recommends policy actions to address these challenges, including data collection, adaptive planning, and cross-border collaboration.