The U.S. Department of Energy’s Oak Ridge National Laboratory has provided hydropower operators with new data to better prepare for extreme weather events and shifts in seasonal energy demands caused by climate change.

For the new report, ORNL researchers used downscaled global climate projections to simulate future hydrologic conditions at 132 federal hydropower facilities across the United States. The resulting projections will enable hydropower operators and policymakers to plan for changing climate conditions and reduced water availability by shifting their operational schedules and their use of water each season as part of an overall mitigation strategy.

“The intensification of future extreme events, including both floods and droughts, is one of the most critical issues threatening the resilience of U.S. hydropower systems and infrastructure,” said Shih-Chieh Kao, water power program manager at ORNL. “This new normal requires us to think differently about current operational practices to adapt to a changing climate.”

n addition to extreme events, a growing conflict in water availability versus energy demand is another challenge for hydropower operators. An earlier-than-expected snowmelt season in the western United States is likely to impact water runoff. This may result in less water for hydropower generation in the summer months, just as energy demand grows. Increased evaporation because of rising temperatures is also putting a strain on water needed for flood control, navigation, municipal water supplies and industrial and agricultural use.

Better understanding of these changes is important to future energy planning. Hydropower provides 35% of renewable energy and nearly 7% of all electricity produced in the U.S.