07/08/2015

Comprehensive View of Global Potential for Hydro-Generated Electricity

Summary

Hydropower, the current dominant renewable energy source, can facilitate the deployment of other variable renewable energy resources used in part to reduce greenhouse gas emissions and provide a stable and sustainable source of electricity. Improved information on hydropower potential and its spatial distribution can help decisionmakers guide the deployment of hydropower plants. Hydropower potential information is also an important input to integrated assessment and energy–economic models, which are used to help explore future energy systems, climate impacts, and transition pathways to lower-carbon futures over decadal to century time scales. In this study, researchers at the Department of Energy’s (DOE) Pacific Northwest National Laboratory assessed global hydropower potential using water runoff and stream flow data, along with turbine technology performance, cost assumptions, and consideration of protected areas. The results provide the first comprehensive quantification of global hydropower potential including: gross, technical, economic, and exploitable. The hydropower is estimated in petawatt hours per year, a measurement defined to quantify electrical use per hour in terms of a quadrillion watts. The research shows that hydropower has the potential to supply a significant portion of world energy needs, although this potential varies substantially by region. Globally, exploitable hydropower potential is comparable to total electricity demand in 2005. Regionally, hydropower plays different roles in each country, mainly because of regional variation in potential relative to electricity demand. In addition, hydropower estimates are sensitive to a number of regionally defined parameters: design capacity, cost assumptions, turbine efficiency, stream flow, fixed charge rate, and protected land. The research emphasizes hydropower’s reliable role for future energy systems, especially when compared to other renewable energy resources with larger uncertainty in their future potentials.

Funding

This work was jointly sponsored by DOE’s Earth System Modeling and Integrated Assessment Research programs.

References

Zhou, Y., M. Hejazi, S. J. Smith, J. A. Edmonds, H.-Y. Li, L. Clarke, K. Calvin, and A. Thomson. 2015. “A Comprehensive View of Global Potential for Hydro-generated Electricity,” Energy & Environmental Science, DOI: 10.1039/C5EE00888C.