Climate Change Impacts on Hydropower Generation

Hydropower remains a cornerstone of global renewable energy, providing a flexible, low-carbon source of electricity. Its viability, however, is intimately tied to hydrological processes that are shifting under a warming climate. Changes in precipitation distribution, snowmelt timing and glacier retreat alter river flow regimes, with many regions facing increased variability between wet and dry seasons. Extreme events such as droughts and heatwaves compound the challenge by simultaneously reducing water availability for generation and elevating energy demand for cooling. At the same time, rising temperatures can modify reservoir evaporation rates and introduce novel operational constraints. Assessment of these impacts has advanced through multi-model ensembles and high-resolution simulations, revealing regionally divergent trajectories: some basins may see modest gains in annual output, while others confront substantial declines. Integrating these projections into planning and system operation is vital for ensuring energy security, guiding infrastructure investment and developing adaptive reservoir management strategies that can buffer against climate-driven shocks.

Research from Nature Portfolio

Recent studies have used extensive weather ensembles to quantify how compound droughts and heatwaves undermine hydropower output and force reliance on fossil-fired plants. By simulating power-system operations under prolonged dry periods, these analyses demonstrate that hydropower deficits coincide with peak anthropogenic demand, leading to elevated emissions and uneven distribution of health impacts. The work highlights the potential of targeted operational and fiscal measures—such as dynamic reservoir release protocols and pollution taxes tied to system stress—to mitigate shortfalls and reduce inequities in environmental health burdens during extreme events.

Climate Change Impacts on Hydropower Generation publication trend

The graph below shows the total number of articles in climate change impacts on hydropower generation across all publications each year (not limited to Nature Index journals).

Technical terms

Runoff: The portion of precipitation that flows over land into rivers and reservoirs, directly influencing hydropower resource availability.

General Circulation Model (GCM): A numerical representation of the Earth’s atmosphere and oceans used to project climate variables such as temperature and precipitation under different greenhouse-gas scenarios.

Representative Concentration Pathway (RCP): A greenhouse-gas concentration trajectory adopted by climate modellers to estimate radiative forcing and associated climate responses over the twenty-first century.

Hydropower Potential: The theoretical or developed capacity of a hydrological system to generate electricity, accounting for flow regimes, head heights and existing infrastructure.

References

1. U.S. West Coast droughts and heat waves exacerbate pollution inequality and can evade emission control policies. Nature Communications (2023).
2. Climate change impacts on the energy system: a review of trends and gaps. Climatic Change (2018).
3. Assessing Climate Change Impacts on Global Hydropower. Energies (2012).
4. Projected impacts of climate change on hydropower potential in China. Hydrology and Earth System Sciences (2016).